/* =============================================================
   MathTalking — theme-v2.css
   Visual v2: tokens + components + floating-glass + workspace
   Opt-in via <html class="visual-v2">. Paired with assets/theme.css
   on pages still on v1. Both stylesheets should not load on the
   same page.
   ============================================================= */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* =========== TOKENS (light default) =========== */
:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --font-math: 'KaTeX_Math', 'Times New Roman', serif;

  --brand:         #1d4ed8;
  --brand-hover:   #1e40af;
  --brand-soft:    #2563eb;
  --accent-cyan:   #06b6d4;
  --accent-green:  #10b981;
  --accent-violet: #7c5cff;
  --accent-warn:   #f59e0b;
  --accent-error:  #dc2626;

  --curve-1: #2563eb;
  --curve-2: #ef4444;
  --curve-3: #10b981;
  --curve-4: #f59e0b;
  --curve-5: #a855f7;

  --bg-app:     #f6f7fb;
  --bg-panel:   #ffffff;
  --bg-sunk:    #f1f3f8;
  --bg-soft:    #eef0f6;
  --bg-tint:    #eff6ff;
  --bg-grid-line: rgba(0,0,0,0.04);

  --ink-1: #0b1020;
  --ink-2: #3b4258;
  --ink-3: #6b7387;
  --ink-4: #9aa1b5;
  --ink-5: #c5c9d6;

  --border:        rgba(15, 23, 42, 0.08);
  --border-strong: rgba(15, 23, 42, 0.14);
  --divider:       rgba(15, 23, 42, 0.06);

  --glass-bg:    rgba(255,255,255,0.72);
  --glass-bg-hi: rgba(255,255,255,0.92);
  --glass-bd:    rgba(255,255,255,0.6);
  --glass-blur:  blur(18px) saturate(180%);

  --shadow-1: 0 1px 2px rgba(9, 14, 30, 0.06);
  --shadow-2: 0 2px 8px rgba(9, 14, 30, 0.08);
  --shadow-3: 0 8px 24px rgba(9, 14, 30, 0.10);
  --shadow-4: 0 20px 60px rgba(9, 14, 30, 0.18);
  --shadow-glow-cyan:  0 0 0 1px rgba(6,182,212,0.35),  0 4px 20px rgba(6,182,212,0.18);
  --shadow-glow-brand: 0 0 0 1px rgba(29,78,216,0.30),  0 4px 20px rgba(29,78,216,0.16);

  --r-1: 6px;
  --r-2: 8px;
  --r-3: 10px;
  --r-4: 14px;
  --r-5: 18px;
  --r-pill: 999px;

  --s-1: 4px;
  --s-2: 8px;
  --s-3: 12px;
  --s-4: 16px;
  --s-5: 20px;
  --s-6: 24px;
  --s-7: 32px;
  --s-8: 48px;

  --ease: cubic-bezier(.2,.7,.2,1);
  --ease-pop: cubic-bezier(.16,1,.3,1);
  --dur-1: 120ms;
  --dur-2: 200ms;
  --dur-3: 320ms;
  --dur-4: 560ms;

  --nav-h: 56px;

  color-scheme: light;
}

/* =========== TOKENS (dark) =========== */
html[data-theme="dark"] {
  --bg-app:   #07090f;
  --bg-panel: #0f1320;
  --bg-sunk:  #0a0d17;
  --bg-soft:  #151a2b;
  --bg-tint:  #102a44;
  --bg-grid-line: rgba(255,255,255,0.05);

  --ink-1: #f3f5fb;
  --ink-2: #c5cbdc;
  --ink-3: #8a92a8;
  --ink-4: #636b81;
  --ink-5: #3a4159;

  --border:        rgba(255,255,255,0.08);
  --border-strong: rgba(255,255,255,0.16);
  --divider:       rgba(255,255,255,0.06);

  --glass-bg:    rgba(15, 19, 32, 0.62);
  --glass-bg-hi: rgba(15, 19, 32, 0.82);
  --glass-bd:    rgba(255,255,255,0.08);

  --shadow-1: 0 1px 2px rgba(0,0,0,0.4);
  --shadow-2: 0 2px 8px rgba(0,0,0,0.5);
  --shadow-3: 0 8px 24px rgba(0,0,0,0.55);
  --shadow-4: 0 24px 80px rgba(0,0,0,0.7);

  --curve-1: #4c8cff;
  --curve-2: #ff6575;
  --curve-3: #2bd4a1;
  --curve-4: #fbbf24;
  --curve-5: #c084fc;

  color-scheme: dark;
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 1ms !important; transition-duration: 1ms !important; }
}

/* =========== BASE =========== */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; }
html.visual-v2 { height: 100%; }
html.visual-v2 body {
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.55;
  color: var(--ink-1);
  background: var(--bg-app);
  -webkit-font-smoothing: antialiased;
  min-height: 100%;
}

html.visual-v2 a { color: var(--brand-soft); text-decoration: none; }
html.visual-v2 a:hover { color: var(--brand); }

html.visual-v2 kbd {
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  color: var(--ink-2);
}

html.visual-v2 ::-webkit-scrollbar { width: 10px; height: 10px; }
html.visual-v2 ::-webkit-scrollbar-thumb {
  background: var(--border-strong); border-radius: 10px;
  border: 2px solid transparent; background-clip: padding-box;
}
html.visual-v2 ::-webkit-scrollbar-thumb:hover { background: var(--ink-4); border: 2px solid transparent; background-clip: padding-box; }
html.visual-v2 ::-webkit-scrollbar-track { background: transparent; }

/* =========== TOPBAR (nav) =========== */
.topbar-v2 {
  display: flex; align-items: center; gap: var(--s-3);
  height: var(--nav-h);
  padding: 0 var(--s-5);
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 40;
}
.topbar-v2.glass {
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom-color: var(--glass-bd);
}
html.visual-v2 .topbar-v2 .brand,
html.visual-v2 .float-top .brand {
  display: inline-flex; align-items: center; gap: var(--s-2);
  font-weight: 700; letter-spacing: -0.01em;
  color: var(--ink-1);
  text-decoration: none;
  font-size: 15px;
  line-height: 1;
  white-space: nowrap;
  flex-shrink: 0;
}
html.visual-v2 .topbar-v2 .brand-mark,
html.visual-v2 .float-top .brand-mark {
  width: 22px; height: 22px;
  flex-shrink: 0;
  display: block;
  border-radius: 6px;
}
.topbar-v2 .spacer { flex: 1; }
.topbar-v2 .nav-slogan {
  font-size: 13px; color: var(--ink-3); font-weight: 400;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  flex: 1 1 auto; min-width: 0;
}

.tab-group {
  display: inline-flex; padding: 3px;
  background: var(--bg-sunk);
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  gap: 2px;
}
.tab {
  appearance: none; border: none; background: transparent;
  font: inherit; color: var(--ink-3);
  padding: 6px 14px; border-radius: var(--r-pill);
  cursor: pointer;
  transition: all var(--dur-2) var(--ease);
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px;
  text-decoration: none;
}
.tab:hover { color: var(--ink-1); }
.tab.active {
  background: var(--bg-panel);
  color: var(--ink-1);
  box-shadow: var(--shadow-1);
}
.tab.active .lucide { color: var(--brand-soft); }

.lang-select-v2 {
  font-family: var(--font-sans);
  font-size: 13px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  background: var(--bg-panel);
  color: var(--ink-2);
  cursor: pointer;
  outline: none;
  transition: border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}
.lang-select-v2:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.12);
}

/* =========== BUTTONS =========== */
.btn-v2 {
  appearance: none; border: 1px solid var(--border);
  background: var(--bg-panel); color: var(--ink-1);
  font: inherit; font-size: 13px; font-weight: 500;
  padding: 7px 14px; border-radius: var(--r-2);
  cursor: pointer;
  display: inline-flex; align-items: center; gap: 6px;
  transition: all var(--dur-2) var(--ease);
  line-height: 1;
  text-decoration: none;
}
.btn-v2:hover { background: var(--bg-soft); border-color: var(--border-strong); }
.btn-v2:active { transform: translateY(1px); }
.btn-v2.btn-primary { background: var(--brand); color: #fff; border-color: var(--brand); }
.btn-v2.btn-primary:hover { background: var(--brand-hover); border-color: var(--brand-hover); }
.btn-v2.btn-ghost { background: transparent; border-color: transparent; color: var(--ink-2); }
.btn-v2.btn-ghost:hover { background: var(--bg-soft); color: var(--ink-1); }
.btn-v2.btn-pill { border-radius: var(--r-pill); }

.icon-btn {
  width: 32px; height: 32px; padding: 0;
  border-radius: var(--r-2);
  background: transparent; border: 1px solid transparent;
  color: var(--ink-2); cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: all var(--dur-2) var(--ease);
}
.icon-btn:hover { background: var(--bg-soft); color: var(--ink-1); }
.icon-btn.active { background: var(--bg-tint); color: var(--brand-soft); }

.theme-toggle {
  width: 32px; height: 32px; border-radius: var(--r-2);
  border: 1px solid transparent; background: transparent;
  color: var(--ink-2); cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: all var(--dur-2) var(--ease);
}
.theme-toggle:hover { background: var(--bg-soft); color: var(--ink-1); }
html.visual-v2 .nav-user { position: relative; }
html.visual-v2 .nav-avatar {
  width: 32px; height: 32px;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand), var(--accent-violet));
  color: #fff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  overflow: hidden;
  box-shadow: var(--shadow-1);
}
html.visual-v2 .nav-avatar-img { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; }
html.visual-v2 .nav-avatar-letter { color: #fff; font-size: 14px; font-weight: 600; }
html.visual-v2 .nav-user-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 190px;
  padding: 8px;
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-3);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  box-shadow: var(--shadow-3);
  z-index: 80;
}
html.visual-v2 .nav-user-info { padding: 5px 8px; font-weight: 600; font-size: 13px; color: var(--ink-1); }
html.visual-v2 .nav-user-tier { padding: 0 8px 7px; font-size: 12px; color: var(--ink-3); }
html.visual-v2 .nav-user-dropdown hr { border: 0; border-top: 1px solid var(--divider); margin: 6px 0; }
html.visual-v2 .nav-user-action {
  display: block;
  width: 100%;
  padding: 8px;
  border: 0;
  border-radius: var(--r-2);
  background: transparent;
  color: var(--ink-2);
  text-align: left;
  font: inherit;
  cursor: pointer;
}
html.visual-v2 .nav-user-action:hover { background: var(--bg-soft); color: var(--ink-1); }

/* =========== Auth / upgrade modals =========== */
html.visual-v2 .login-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(4, 10, 24, 0.46);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  pointer-events: auto;
}
html.visual-v2 .login-modal {
  position: relative;
  width: min(420px, calc(100vw - 32px));
  max-width: 100%;
  padding: 28px;
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-5);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  box-shadow: var(--shadow-4);
  color: var(--ink-1);
  pointer-events: auto;
}
html.visual-v2 .login-close {
  position: absolute;
  top: 10px;
  right: 12px;
  width: 32px;
  height: 32px;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--ink-3);
  font-size: 24px;
  line-height: 1;
  cursor: pointer;
}
html.visual-v2 .login-close:hover {
  background: var(--bg-soft);
  color: var(--ink-1);
}
html.visual-v2 .login-title {
  margin: 0 0 8px;
  font-size: 22px;
  line-height: 1.2;
  font-weight: 700;
  text-align: center;
}
html.visual-v2 .login-subtitle {
  margin: 0 0 22px;
  font-size: 14px;
  color: var(--ink-3);
  text-align: center;
}
html.visual-v2 .login-buttons {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
html.visual-v2 .login-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 100%;
  min-height: 44px;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: var(--r-2);
  background: var(--bg-panel);
  color: var(--ink-1);
  font: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--dur-2) var(--ease), border-color var(--dur-2) var(--ease), transform var(--dur-2) var(--ease);
}
html.visual-v2 .login-btn:hover {
  background: var(--bg-soft);
  border-color: var(--border-strong);
}
html.visual-v2 .login-btn:active {
  transform: translateY(1px);
}
html.visual-v2 .login-btn svg {
  flex-shrink: 0;
}
html.visual-v2 .login-btn-google,
html.visual-v2 .login-btn-email {
  background: var(--bg-panel);
  color: var(--ink-1);
}
html.visual-v2 .login-btn-apple {
  background: #111;
  border-color: #111;
  color: #fff;
}
html.visual-v2 .login-btn-apple:hover {
  background: #222;
  border-color: #222;
}
html.visual-v2 .login-btn-send,
html.visual-v2 .login-btn-verify,
html.visual-v2 .upgrade-btn-signin,
html.visual-v2 .upgrade-btn-pro {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}
html.visual-v2 .login-btn-send:hover,
html.visual-v2 .login-btn-verify:hover,
html.visual-v2 .upgrade-btn-signin:hover,
html.visual-v2 .upgrade-btn-pro:hover {
  background: var(--brand-hover);
  border-color: var(--brand-hover);
}
html.visual-v2 .login-divider {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--ink-4);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
html.visual-v2 .login-divider::before,
html.visual-v2 .login-divider::after {
  content: '';
  flex: 1;
  border-top: 1px solid var(--divider);
}
html.visual-v2 .login-email-form,
html.visual-v2 .login-otp-form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
html.visual-v2 .login-email-input,
html.visual-v2 .login-otp-input {
  width: 100%;
  min-height: 44px;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: var(--r-2);
  background: var(--bg-sunk);
  color: var(--ink-1);
  font: inherit;
  outline: none;
}
html.visual-v2 .login-email-input:focus,
html.visual-v2 .login-otp-input:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px color-mix(in oklch, var(--brand) 18%, transparent);
  background: var(--bg-panel);
}
html.visual-v2 .login-otp-input {
  text-align: center;
  letter-spacing: 6px;
  font-size: 22px;
  font-weight: 700;
}
html.visual-v2 .login-otp-label {
  margin: 0;
  font-size: 13px;
  color: var(--ink-3);
  text-align: center;
}
html.visual-v2 .login-link {
  align-self: center;
  border: 0;
  background: transparent;
  color: var(--brand);
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}
html.visual-v2 .login-link:hover {
  text-decoration: underline;
}
html.visual-v2 .login-error {
  margin: 0;
  color: var(--accent-error);
  font-size: 13px;
  text-align: center;
}
html.visual-v2 .upgrade-icon {
  margin-bottom: 8px;
  text-align: center;
  font-size: 34px;
}

/* =========== PANEL / CARD (float) =========== */
.panel {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--r-4);
  display: flex; flex-direction: column;
  min-height: 0;
  box-shadow: var(--shadow-1);
  overflow: hidden;
}
.panel-head {
  display: flex; align-items: center; gap: var(--s-2);
  height: 38px; padding: 0 12px;
  border-bottom: 1px solid var(--divider);
  color: var(--ink-3);
  font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase;
  font-weight: 600;
  flex-shrink: 0;
}
.panel-body { flex: 1 1 0; min-height: 0; overflow: auto; padding: 12px; }

.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  box-shadow: var(--shadow-3);
}

/* =========== INPUTS =========== */
.input, .textarea {
  width: 100%;
  padding: 8px 12px;
  font: inherit; font-size: 13px;
  border: 1px solid var(--border);
  background: var(--bg-sunk);
  color: var(--ink-1);
  border-radius: var(--r-2);
  outline: none;
  transition: border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}
.input:focus, .textarea:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.12);
  background: var(--bg-panel);
}
.input.mono { font-family: var(--font-mono); font-size: 13px; }
.textarea { resize: vertical; min-height: 96px; }

/* =========== LUCIDE =========== */
.lucide {
  width: 16px; height: 16px;
  stroke-width: 1.5;
  flex-shrink: 0;
}

/* =========== CHIP =========== */
.chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 5px 10px;
  border-radius: var(--r-pill);
  font-size: 12px; font-weight: 500;
  background: var(--bg-soft); color: var(--ink-2);
  border: 1px solid var(--border);
}
.chip.live {
  background: color-mix(in oklch, var(--accent-green) 14%, var(--bg-panel));
  color: var(--accent-green);
  border-color: color-mix(in oklch, var(--accent-green) 30%, transparent);
}
.chip.ai {
  background: color-mix(in oklch, var(--accent-violet) 14%, var(--bg-panel));
  color: var(--accent-violet);
  border-color: color-mix(in oklch, var(--accent-violet) 30%, transparent);
}

.dot-pulse {
  width: 6px; height: 6px; border-radius: 50%;
  background: currentColor;
  animation: dot-pulse 1.6s var(--ease) infinite;
}
@keyframes dot-pulse {
  0%   { box-shadow: 0 0 0 0 color-mix(in oklch, currentColor 40%, transparent); }
  70%  { box-shadow: 0 0 0 6px color-mix(in oklch, currentColor 0%, transparent); }
  100% { box-shadow: 0 0 0 0 color-mix(in oklch, currentColor 0%, transparent); }
}

/* =========== CHAT BUBBLES =========== */
.thread {
  display: flex; flex-direction: column; gap: 10px; padding: 12px;
}
.bubble {
  font-size: 13px; line-height: 1.55;
  max-width: 88%; padding: 8px 12px;
  border-radius: var(--r-3);
}
.bubble.user {
  align-self: flex-end;
  background: var(--bg-soft); color: var(--ink-1);
  border-radius: var(--r-3) var(--r-3) 2px var(--r-3);
}
.bubble.ai, .bubble.assistant {
  align-self: flex-start;
  background: color-mix(in oklch, var(--accent-violet) 8%, var(--bg-panel));
  color: var(--ink-1);
  border: 1px solid color-mix(in oklch, var(--accent-violet) 24%, transparent);
  border-radius: var(--r-3) var(--r-3) var(--r-3) 2px;
}
.bubble.tool {
  align-self: flex-start;
  background: transparent;
  color: var(--ink-3); font-size: 12px; font-style: italic;
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 0;
}

.thinking {
  display: inline-flex; gap: 4px; padding: 10px 14px;
  align-self: flex-start;
  background: color-mix(in oklch, var(--accent-violet) 8%, var(--bg-panel));
  border: 1px solid color-mix(in oklch, var(--accent-violet) 24%, transparent);
  border-radius: var(--r-3);
}
.thinking span {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent-violet);
  animation: tb 1.2s ease-in-out infinite;
}
.thinking span:nth-child(2) { animation-delay: 0.15s; }
.thinking span:nth-child(3) { animation-delay: 0.3s; }
@keyframes tb {
  0%,80%,100% { transform: translateY(0); opacity: 0.4; }
  40%         { transform: translateY(-5px); opacity: 1; }
}

/* =========== LANDING (welcome page) =========== */
.landing-v2 {
  min-height: calc(100vh - var(--nav-h));
  padding: 48px 24px 80px;
  display: flex; flex-direction: column; align-items: center;
  background:
    radial-gradient(900px 500px at 15% 10%, color-mix(in oklch, var(--accent-cyan) 12%, transparent), transparent 60%),
    radial-gradient(900px 600px at 85% 90%, color-mix(in oklch, var(--accent-violet) 14%, transparent), transparent 60%),
    var(--bg-app);
}
.landing-hero {
  max-width: 720px;
  text-align: center;
  margin-bottom: 48px;
}
.landing-hero .eyebrow {
  font-size: 12px; text-transform: uppercase; letter-spacing: .14em;
  color: var(--brand); font-weight: 600;
  margin-bottom: 14px;
}
.landing-hero h1 {
  font-size: clamp(32px, 5vw, 52px); font-weight: 600;
  letter-spacing: -0.025em; line-height: 1.05;
  margin: 0 0 18px;
  color: var(--ink-1);
}
.landing-hero h1 em {
  font-style: normal;
  background: linear-gradient(90deg, var(--accent-cyan), var(--brand), var(--accent-violet));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.landing-hero .sub {
  font-size: 16px; color: var(--ink-2); line-height: 1.55;
  max-width: 620px; margin: 0 auto;
}

.landing-grid {
  width: 100%;
  max-width: 1200px;
  display: grid; gap: 20px;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}
.product-card {
  display: flex; flex-direction: column;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--r-4);
  overflow: hidden;
  text-decoration: none; color: inherit;
  transition: transform var(--dur-2) var(--ease),
              box-shadow var(--dur-2) var(--ease),
              border-color var(--dur-2) var(--ease);
}
.product-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-3);
  border-color: color-mix(in oklch, var(--brand) 50%, var(--border));
}
.card-preview {
  aspect-ratio: 16 / 10;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--divider);
  background: var(--bg-sunk);
}
.card-preview canvas,
.card-preview iframe {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  display: block; border: 0;
}
.card-body { padding: 18px 22px 22px; }
.card-tag {
  display: inline-flex; align-items: center;
  height: 22px; padding: 0 10px;
  border-radius: var(--r-pill);
  font-size: 11px; font-weight: 600;
  letter-spacing: .06em; text-transform: uppercase;
  margin-bottom: 10px;
}
.card-tag.tag-math { background: color-mix(in oklch, var(--brand) 18%, transparent);        color: var(--brand); }
.card-tag.tag-stat { background: color-mix(in oklch, var(--accent-cyan) 18%, transparent);  color: var(--accent-cyan); }
.card-tag.tag-3d   { background: color-mix(in oklch, var(--accent-violet) 18%, transparent); color: var(--accent-violet); }
.card-title { font-size: 19px; font-weight: 600; margin: 0 0 6px; letter-spacing: -0.01em; color: var(--ink-1); }
.card-note { font-size: 13px; color: var(--ink-2); line-height: 1.55; }
.card-foot {
  margin-top: 16px; display: flex; align-items: center; gap: 6px;
  font-size: 12px; color: var(--brand); font-weight: 600;
}
.card-foot-arrow { transition: transform var(--dur-2) var(--ease); display: inline-block; }
.product-card:hover .card-foot-arrow { transform: translateX(3px); }

.landing-footnote {
  margin-top: 48px; text-align: center;
  font-size: 12px; color: var(--ink-3);
}

/* =========== FOOTER =========== */
html.visual-v2 .site-footer {
  margin: 40px auto 24px;
  width: min(960px, calc(100% - 32px));
  padding: 18px 20px;
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-4);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  box-shadow: var(--shadow-2);
  color: var(--ink-3);
  font-size: 13px;
  text-align: center;
}
html.visual-v2 .site-footer-inner { max-width: 1200px; margin: 0 auto; }
html.visual-v2 .site-footer p { margin: 4px 0; }
html.visual-v2 .site-footer-divider { display: none; }
html.visual-v2 .site-footer a { color: var(--ink-2); text-decoration: none; }
html.visual-v2 .site-footer a:hover { color: var(--ink-1); }
html.visual-v2 .footer-social {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin: 10px 0 4px;
}
html.visual-v2 .footer-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 999px;
  border: 1px solid transparent;
}
html.visual-v2 .footer-social a:hover {
  background: color-mix(in oklab, var(--bg-panel) 76%, transparent);
  border-color: var(--divider);
}
html.visual-v2 .footer-social svg { display: block; }
html.visual-v2 body:has(.v2-app) > .site-footer {
  position: relative;
  left: auto;
  top: auto;
  width: min(960px, calc(100% - 32px));
  height: auto;
  overflow: visible;
  margin: 12px auto 24px;
  z-index: 1;
}
html.visual-v2 body.classes-v3-page > .site-footer {
  position: relative;
  width: min(1240px, calc(100% - 32px));
  margin: 28px auto 24px;
}

/* =========== CLASSES WORKSPACE =========== */
html.visual-v2 body.classes-v3-page {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(1200px 720px at 12% 8%, color-mix(in oklch, var(--accent-cyan) 10%, transparent), transparent 60%),
    radial-gradient(1000px 680px at 88% 16%, color-mix(in oklch, var(--accent-violet) 10%, transparent), transparent 62%),
    var(--bg-app);
}
html.visual-v2[data-theme="dark"] body.classes-v3-page {
  background:
    radial-gradient(1200px 720px at 12% 8%, color-mix(in oklch, var(--accent-cyan) 18%, transparent), transparent 60%),
    radial-gradient(1000px 680px at 88% 16%, color-mix(in oklch, var(--accent-violet) 18%, transparent), transparent 62%),
    var(--bg-app);
}
html.visual-v2 body.classes-v3-page > .float-top {
  position: sticky;
  top: 14px;
  left: auto;
  right: auto;
  width: min(1380px, calc(100% - 32px));
  margin: 14px auto 0;
}
html.visual-v2 .classes-v3-shell {
  width: min(1380px, calc(100% - 32px));
  margin: 0 auto;
  padding: 84px 0 0;
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  grid-template-areas:
    "rail main"
    "guide guide";
  grid-template-rows: auto auto;
  gap: 18px;
  align-items: stretch;
}
html.visual-v2 .classes-rail {
  grid-area: rail;
  display: flex;
  min-width: 0;
  min-height: 0;
}
html.visual-v2 .classes-rail-card,
html.visual-v2 .classes-main-card {
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-4);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  box-shadow: var(--shadow-2);
  display: flex;
  flex-direction: column;
  min-height: 0;
}
html.visual-v2 .classes-rail-card {
  padding: 18px 18px 20px;
}
html.visual-v2 .classes-main-card {
  padding: 24px 24px 20px;
}
html.visual-v2 .classes-nav-card,
html.visual-v2 .classes-main-card {
  flex: 1 1 auto;
  height: 100%;
}
html.visual-v2 .classes-guide-card {
  grid-area: guide;
  padding: 20px 22px 22px;
}
html.visual-v2 .classes-card-eyebrow {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-3);
  font-weight: 600;
  margin-bottom: 6px;
}
html.visual-v2 .classes-rail-title {
  margin: 0 0 14px;
  font-size: 18px;
  line-height: 1.2;
  color: var(--ink-1);
}
html.visual-v2 .classes-workspace {
  grid-area: main;
  display: flex;
  min-width: 0;
  min-height: 0;
  padding-bottom: 8px;
}
html.visual-v2 .classes-workspace-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 22px;
}
html.visual-v2 .classes-workspace-copy { min-width: 0; }
html.visual-v2 .lesson-heading {
  font-size: 30px;
  line-height: 1.08;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink-1);
  margin: 0 0 6px;
}
html.visual-v2 .lesson-subheading {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-3);
  max-width: 720px;
}
html.visual-v2 .classes-kpi-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
html.visual-v2 .classes-kpi {
  min-width: 92px;
  padding: 12px 14px;
  border-radius: var(--r-3);
  border: 1px solid var(--divider);
  background: color-mix(in oklch, var(--bg-panel) 76%, transparent);
}
html.visual-v2 .classes-kpi-label {
  display: block;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-4);
  margin-bottom: 5px;
}
html.visual-v2 .classes-kpi-value {
  display: block;
  font-size: 20px;
  line-height: 1;
  color: var(--ink-1);
}
html.visual-v2 .classes-section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
}
html.visual-v2 .class-cat-heading {
  margin: 0;
  font-size: 20px;
  line-height: 1.2;
  font-weight: 600;
  color: var(--ink-1);
}
html.visual-v2 .classes-section-count {
  flex-shrink: 0;
  padding: 7px 12px;
  border-radius: var(--r-pill);
  border: 1px solid var(--divider);
  background: var(--bg-panel-soft);
  font-size: 12px;
  color: var(--ink-3);
  font-weight: 600;
}
html.visual-v2 .classes-toc {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
html.visual-v2 .toc-cat-btn {
  display: block;
  width: 100%;
  padding: 10px 12px;
  border: 1px solid transparent;
  border-radius: var(--r-2);
  background: transparent;
  color: var(--ink-2);
  font-size: 13px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: all var(--dur-2) var(--ease);
}
html.visual-v2 .toc-cat-btn:hover {
  background: var(--bg-soft);
  color: var(--ink-1);
}
html.visual-v2 .toc-cat-btn.toc-active {
  background: color-mix(in oklch, var(--brand) 12%, var(--bg-panel));
  border-color: color-mix(in oklch, var(--brand) 28%, transparent);
  color: var(--brand-soft);
}
html.visual-v2 .toc-cat-btn.toc-disabled {
  cursor: default;
  color: var(--ink-4);
}
html.visual-v2 .toc-soon {
  margin-left: 6px;
  font-size: 10px;
  font-weight: 500;
  color: var(--ink-4);
}
html.visual-v2 .toc-lessons {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 2px 0 8px 10px;
  max-height: 420px;
  overflow: hidden;
  transition: max-height var(--dur-3) var(--ease), padding var(--dur-2) var(--ease);
}
html.visual-v2 .toc-lessons.toc-collapsed {
  max-height: 0;
  padding-top: 0;
  padding-bottom: 0;
}
html.visual-v2 .toc-lesson {
  display: block;
  padding: 6px 10px;
  border-radius: var(--r-2);
  color: var(--ink-3);
  font-size: 12px;
  line-height: 1.4;
  text-decoration: none;
  transition: all var(--dur-2) var(--ease);
}
html.visual-v2 .toc-lesson:hover {
  background: var(--bg-soft);
  color: var(--ink-1);
}
html.visual-v2 .toc-divider {
  margin: 8px 0 4px;
  border: 0;
  border-top: 1px solid var(--divider);
}
html.visual-v2 .class-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 12px;
}
html.visual-v2 .class-card {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  min-height: 118px;
  padding: 16px;
  border-radius: var(--r-3);
  border: 1px solid var(--divider);
  background: color-mix(in oklch, var(--bg-panel) 78%, transparent);
  text-decoration: none;
  color: inherit;
  transition: transform var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease), border-color var(--dur-2) var(--ease), background var(--dur-2) var(--ease);
}
html.visual-v2 .class-card:hover {
  transform: translateY(-2px);
  border-color: color-mix(in oklch, var(--brand) 32%, transparent);
  background: color-mix(in oklch, var(--bg-panel) 86%, var(--bg-tint));
  box-shadow: var(--shadow-3);
}
html.visual-v2 .class-icon {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  background: color-mix(in oklch, var(--brand) 12%, var(--bg-panel));
  font-size: 20px;
}
html.visual-v2 .class-info {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
html.visual-v2 .class-title {
  display: block;
  font-size: 15px;
  line-height: 1.35;
  font-weight: 600;
  color: var(--ink-1);
}
html.visual-v2 .class-desc {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  font-size: 12px;
  line-height: 1.55;
  color: var(--ink-3);
}
html.visual-v2 .class-level {
  display: inline-flex;
  align-items: center;
  align-self: flex-start;
  height: 22px;
  padding: 0 9px;
  border-radius: var(--r-pill);
  background: color-mix(in oklch, var(--accent-cyan) 10%, transparent);
  color: var(--accent-cyan);
  font-size: 11px;
  font-weight: 600;
}
html.visual-v2 .class-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-left: 6px;
  border-radius: 50%;
  vertical-align: middle;
}
html.visual-v2 .dot-wip { background: var(--accent-cyan); }
html.visual-v2 .dot-done { background: var(--accent-green); }
html.visual-v2 .qna-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
html.visual-v2 .qna-item {
  padding-top: 12px;
  border-top: 1px solid var(--divider);
}
html.visual-v2 .qna-item:first-child {
  padding-top: 0;
  border-top: 0;
}
html.visual-v2 .qna-q {
  margin: 0 0 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink-1);
  font-weight: 600;
}
html.visual-v2 .qna-a {
  margin: 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--ink-3);
}
html.visual-v2 .class-coming-soon {
  margin: 18px 0 0;
  font-size: 12px;
  color: var(--ink-4);
  text-align: center;
}

/* =========== RESPONSIVE =========== */
@media (max-width: 1100px) {
  .topbar-v2 .nav-slogan { display: none; }
  html.visual-v2 .classes-v3-shell {
    grid-template-columns: 280px minmax(0, 1fr);
  }
}
@media (max-width: 768px) {
  .landing-v2 { padding: 32px 16px 48px; }
  .landing-grid { grid-template-columns: 1fr; gap: 14px; }
  .landing-hero { margin-bottom: 32px; }
  .topbar-v2 { padding: 0 12px; gap: 8px; }
  .topbar-v2 .tab-group { padding: 2px; }
  .topbar-v2 .tab { padding: 5px 10px; font-size: 12px; }
  html.visual-v2 .classes-v3-shell {
    width: calc(100% - 24px);
    padding-top: 72px;
    grid-template-columns: 1fr;
    grid-template-areas:
      "rail"
      "main"
      "guide";
    grid-template-rows: auto;
  }
  html.visual-v2 .classes-nav-card,
  html.visual-v2 .classes-main-card { height: auto; }
  html.visual-v2 .classes-workspace-header,
  html.visual-v2 .classes-section-head {
    flex-direction: column;
    align-items: flex-start;
  }
  html.visual-v2 .classes-main-card {
    padding: 20px 18px 18px;
  }
}
@media (max-width: 480px) {
  .topbar-v2 .lang-select-v2 { display: none; }
  .topbar-v2 .tab-group { overflow-x: auto; scrollbar-width: none; max-width: 60vw; }
  .landing-hero h1 { font-size: 28px; }
  html.visual-v2 .class-list { grid-template-columns: 1fr; }
}

/* =========== SEO content visible to crawlers but hidden for humans =========== */
html.visual-v2 .seo-content.sr-only,
html.visual-v2 .seo-content {
  /* Default: keep visible below landing-grid for crawlers + power users */
  margin: 48px auto 0;
  max-width: 1200px;
  padding: 0 16px;
}
html.visual-v2 .seo-content h2 { color: var(--ink-2); }
html.visual-v2 .seo-content details { margin: 8px 0; }

/* On a v2 canvas-page (math/stat/3d), SEO content stays in DOM for crawlers
   but is visually collapsed. Lesson-info panel clones the relevant content. */
html.visual-v2 .page-canvas + .seo-content,
html.visual-v2 body > .seo-content:last-of-type {
  position: absolute; left: -9999px; top: auto; width: 1px; height: 1px; overflow: hidden;
}

/* =========== V2 CANVAS PAGE (math / stat / 3d) =========== */
/* Layout ported from ../lyncius/Mathtalking Design System/v2/v2.css */
html.visual-v2 .v2-app {
  position: fixed; inset: 0;
  overflow: hidden; background: var(--bg-app);
}
html.visual-v2 body:has(.v2-app) > .v2-app {
  position: sticky;
  inset: auto;
  top: 0;
  width: 100%;
  height: 100vh;
}
html.visual-v2 .v2-canvas {
  position: absolute; inset: 0;
  background:
    radial-gradient(1400px 800px at 20% 10%, color-mix(in oklch, var(--accent-cyan) 10%, transparent), transparent 60%),
    radial-gradient(1200px 700px at 85% 90%, color-mix(in oklch, var(--accent-violet) 10%, transparent), transparent 60%),
    radial-gradient(circle at 1.5px 1.5px, var(--bg-grid-line) 1.5px, transparent 0) 0 0 / 28px 28px,
    var(--bg-panel);
}
html.visual-v2[data-theme="dark"] .v2-canvas {
  background:
    radial-gradient(1400px 800px at 20% 10%, color-mix(in oklch, var(--accent-cyan) 22%, transparent), transparent 60%),
    radial-gradient(1200px 700px at 85% 90%, color-mix(in oklch, var(--accent-violet) 20%, transparent), transparent 60%),
    radial-gradient(circle at 1.5px 1.5px, var(--bg-grid-line) 1.5px, transparent 0) 0 0 / 28px 28px,
    var(--bg-panel);
}
html.visual-v2 .v2-canvas .graph-container,
html.visual-v2 .v2-canvas #graphContainer {
  position: absolute; inset: 0;
  background: transparent;
  border: 0;
}
html.visual-v2 .v2-canvas #graphCanvas,
html.visual-v2 .v2-canvas #threeContainer {
  width: 100%; height: 100%; display: block;
}

/* =========== Top floating bar (pill) =========== */
/* Relies on `.glass` for backdrop-filter + background. Don't duplicate
   those here — differences would drift from the mock. */
html.visual-v2 .global-nav.float-top,
html.visual-v2 .float-top {
  position: absolute;
  top: 14px; left: 14px; right: 14px;
  height: 48px; padding: 0 10px 0 14px;
  display: flex; align-items: center; gap: 10px;
  border-radius: var(--r-pill);
  z-index: 30;
  /* Hidden until nav-v2.js adds .ready to avoid empty-pill flash */
  opacity: 0;
  transition: opacity var(--dur-2) var(--ease);
}
html.visual-v2 .global-nav.float-top.ready,
html.visual-v2 .float-top.ready { opacity: 1; }
html.visual-v2 .float-top .divider-v {
  width: 1px; height: 22px; background: var(--divider); flex-shrink: 0;
}
html.visual-v2 .float-top .spacer { flex: 1 1 auto; min-width: 0; }
html.visual-v2 .float-top .nav-slogan {
  font-size: 13px; color: var(--ink-3); font-weight: 400;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  flex: 1 1 auto; min-width: 0;
}
html.visual-v2 .float-top .panel-switcher {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
html.visual-v2 .float-top .nav-live {
  white-space: nowrap;
  flex-shrink: 0;
}

/* Full-canvas overlay host for show notes, calculator panels, and overview buttons. */
html.visual-v2 .v2-overlay-host {
  position: absolute;
  inset: 0;
  z-index: 16;
  pointer-events: none;
}
html.visual-v2 .v2-overlay-host > * { pointer-events: auto; }

/* =========== Right-side control column =========== */
html.visual-v2 .float-tools {
  position: absolute;
  top: 76px; right: 20px;
  display: flex; flex-direction: column; gap: 3px;
  padding: 4px; border-radius: var(--r-3);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  box-shadow: var(--shadow-2);
  z-index: 20;
}
html.visual-v2 .float-tools .toolbar-btn,
html.visual-v2 .float-tools .icon-btn {
  width: 34px; height: 34px;
  background: transparent; border: 1px solid transparent;
  color: var(--ink-2); cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  border-radius: var(--r-2);
  font-size: 16px;
  transition: all var(--dur-2) var(--ease);
}
html.visual-v2 .float-tools .toolbar-btn:hover,
html.visual-v2 .float-tools .icon-btn:hover { background: var(--bg-soft); color: var(--ink-1); }
html.visual-v2 .float-tools .icon-btn.active {
  background: var(--bg-tint);
  color: var(--brand-soft);
}
html.visual-v2 .float-tools #playModeBtn.active {
  background:
    radial-gradient(circle at 32% 28%, rgba(255,255,255,0.38), transparent 42%),
    linear-gradient(135deg,
      color-mix(in oklab, var(--accent-cyan) 68%, var(--bg-panel)),
      color-mix(in oklab, var(--accent-violet) 62%, var(--bg-panel))
    );
  color: #fff;
  border-color: color-mix(in oklab, var(--accent-cyan) 36%, transparent);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.32),
    0 10px 22px color-mix(in oklab, var(--accent-violet) 18%, transparent);
}
html.visual-v2 .float-tools .divider-h {
  height: 1px; background: var(--divider); margin: 4px 2px;
}

/* Share + theme dropdowns on canvas */
html.visual-v2 .share-dropdown,
html.visual-v2 .theme-dropdown {
  position: absolute; top: 100%; right: 0; margin-top: 6px;
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-3);
  box-shadow: var(--shadow-3);
  padding: 4px; min-width: 180px; z-index: 30;
  display: none; flex-direction: column; gap: 2px;
}
html.visual-v2 .share-dropdown.open,
html.visual-v2 .theme-dropdown.open { display: flex; }
html.visual-v2 .share-option,
html.visual-v2 .theme-option {
  display: block; width: 100%; padding: 7px 12px; text-align: left;
  border: none; background: transparent; color: var(--ink-1);
  font: inherit; font-size: 13px; cursor: pointer;
  border-radius: var(--r-2);
}
html.visual-v2 .share-option:hover,
html.visual-v2 .theme-option:hover { background: var(--bg-soft); }

/* =========== Float panels (objects, lesson-info, etc.) =========== */
html.visual-v2 .float-panel {
  position: absolute;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-4);
  box-shadow: var(--shadow-3);
  display: flex; flex-direction: column;
  min-height: 340px;
  height: min(52vh, calc(100vh - var(--nav-h) - 156px));
  max-height: calc(100vh - var(--nav-h) - 120px);
  overflow: hidden;
  z-index: 18;
  animation: panel-in var(--dur-3) var(--ease-pop);
}
@keyframes panel-in {
  from { opacity: 0; transform: translateY(8px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}
html.visual-v2 .float-panel[hidden] { display: none; }

html.visual-v2 .float-head {
  display: flex; align-items: center; gap: 8px;
  height: 36px; padding: 0 8px 0 12px;
  border-bottom: 1px solid var(--divider);
  font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-2);
  flex-shrink: 0;
}
html.visual-v2 .float-head .float-title { flex: 1; }
html.visual-v2 .float-head .float-close { color: var(--ink-3); }
html.visual-v2 .float-head .head-select {
  max-width: 158px;
  height: 28px;
  padding: 0 28px 0 10px;
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  background: var(--bg-panel);
  color: var(--ink-2);
  font: inherit;
  font-size: 12px;
  outline: none;
}
html.visual-v2 .float-body {
  padding: 12px;
  overflow-y: auto;
  flex: 1 1 0; min-height: 0;
  color: var(--ink-1);
  font-size: 13px; line-height: 1.55;
}
html.visual-v2 .float-panel.float-objects .float-body {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
html.visual-v2 .float-body :where(h1,h2,h3) { font-weight: 600; margin: 12px 0 6px; }
html.visual-v2 .float-body h1 { font-size: 17px; }
html.visual-v2 .float-body h2 { font-size: 15px; color: var(--ink-2); }
html.visual-v2 .float-body h3 { font-size: 13px; color: var(--ink-2); }
html.visual-v2 .float-body p  { margin: 0 0 8px; color: var(--ink-2); }
html.visual-v2 .float-body details { border-top: 1px solid var(--divider); padding: 8px 0; }
html.visual-v2 .float-body details:first-of-type { border-top: none; }
html.visual-v2 .float-body summary { cursor: pointer; font-weight: 500; color: var(--ink-1); }

/* Panel positions */
html.visual-v2 .float-panel.float-objects {
  top: auto;
  bottom: 152px;
  left: 20px;
  width: 380px;
  min-height: 280px;
  height: min(38vh, 420px);
}
html.visual-v2 .float-panel.float-lesson-info {
  top: 76px; right: 76px;
  width: min(420px, calc(100vw - 168px));
  min-height: 220px;
  height: min(36vh, 300px);
  max-height: calc(100vh - var(--nav-h) - 188px);
}
html.visual-v2 .float-panel.float-faq {
  top: auto;
  bottom: 152px;
  right: 76px;
  width: min(420px, calc(100vw - 168px));
  min-height: 260px;
  height: min(34vh, 360px);
}
html.visual-v2 .float-panel.float-suggested {
  top: auto;
  bottom: 152px;
  right: 76px;
  width: min(420px, calc(100vw - 168px));
  min-height: 220px;
  height: min(30vh, 320px);
}
html.visual-v2 .float-panel.float-data {
  top: auto;
  bottom: 152px;
  left: 20px;
  width: min(420px, calc(100vw - 168px));
  min-height: 300px;
  height: min(40vh, 440px);
}

/* Objects func-list + input styling inside float panel */
html.visual-v2 .float-panel .func-list {
  display: flex; flex-direction: column; gap: 4px;
}
html.visual-v2 .float-panel.float-objects .func-list {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
}
html.visual-v2 .float-panel .func-input-row {
  display: flex; gap: 6px; margin-top: 8px;
  border-top: 1px solid var(--divider); padding-top: 10px;
}
html.visual-v2 .float-panel.float-objects .func-input-row {
  margin-top: auto;
  flex-shrink: 0;
}
html.visual-v2 .float-panel .func-input {
  flex: 1; padding: 7px 10px;
  font: inherit; font-family: var(--font-mono); font-size: 13px;
  border: 1px solid var(--border); background: var(--bg-sunk);
  color: var(--ink-1); border-radius: var(--r-2); outline: none;
}
html.visual-v2 .float-panel .func-input:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.12);
  background: var(--bg-panel);
}
html.visual-v2 .float-panel .func-add-btn {
  width: 32px; height: 32px;
  background: var(--brand); color: #fff;
  border: none; border-radius: var(--r-2);
  font-size: 18px; cursor: pointer;
  transition: background var(--dur-2) var(--ease);
}
html.visual-v2 .float-panel .func-add-btn:hover { background: var(--brand-hover); }
html.visual-v2 .float-panel .obj-group-heading {
  padding: 6px 2px 2px;
  color: var(--ink-4);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
}
html.visual-v2 .float-panel .func-item {
  border-bottom: 0;
  padding: 0;
}
html.visual-v2 .float-panel .func-row {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 7px 8px;
  border-radius: var(--r-2);
  transition: background var(--dur-2) var(--ease);
}
html.visual-v2 .float-panel .func-row:hover { background: var(--bg-soft); }
html.visual-v2 .float-panel .func-color-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  border: 0;
  box-shadow: 0 0 8px currentColor;
  flex-shrink: 0;
}
html.visual-v2 .float-panel .func-label {
  flex: 1 1 auto;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-1);
}
html.visual-v2 .float-panel .func-btn {
  width: 22px; height: 22px;
  border: 1px solid transparent;
  border-radius: var(--r-2);
  background: transparent;
  color: var(--ink-4);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
html.visual-v2 .float-panel .func-btn:hover {
  background: var(--bg-soft);
  color: var(--ink-1);
}

html.visual-v2 .float-panel .hot-banner,
html.visual-v2 .float-panel .lesson-related {
  margin: 0 0 14px;
}
html.visual-v2 .float-panel .hot-banner-title,
html.visual-v2 .float-panel .lesson-related h3 {
  margin: 0 0 10px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-1);
}
html.visual-v2 .float-panel .hot-cards,
html.visual-v2 .float-panel .lesson-related-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
html.visual-v2 .float-panel .lesson-link {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 12px;
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  background: var(--bg-panel);
  color: var(--brand-soft);
  font-size: 12px;
  font-weight: 500;
  text-decoration: none;
  transition: background var(--dur-2) var(--ease), border-color var(--dur-2) var(--ease), color var(--dur-2) var(--ease);
}
html.visual-v2 .float-panel .lesson-link:hover {
  background: var(--bg-tint);
  border-color: color-mix(in oklch, var(--brand) 30%, transparent);
  color: var(--brand);
}

html.visual-v2 .float-panel.float-data .float-body {
  display: flex;
  flex-direction: column;
  gap: 10px;
  overflow: hidden;
}
html.visual-v2 .float-panel.float-data .stat-data-hint {
  margin: 0;
  color: var(--ink-3);
  font-size: 12px;
}
html.visual-v2 .float-panel.float-data .stat-data-textarea {
  width: 100%;
  flex: 1 1 auto;
  min-height: 0;
  padding: 12px;
  resize: none;
  border: 1px solid var(--border);
  border-radius: var(--r-3);
  background: var(--bg-sunk);
  color: var(--ink-1);
  font: 12px/1.55 var(--font-mono);
  outline: none;
}
html.visual-v2 .float-panel.float-data .stat-data-textarea:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.12);
  background: var(--bg-panel);
}
html.visual-v2 .float-panel.float-data .stat-summary {
  flex: 0 0 auto;
  max-height: 132px;
  overflow: auto;
  padding: 10px 12px;
  border: 1px solid var(--divider);
  border-radius: var(--r-3);
  background: color-mix(in oklch, var(--bg-panel) 84%, transparent);
  color: var(--ink-2);
  font-size: 12px;
}
html.visual-v2 .float-panel.float-data .stat-summary:empty {
  display: none;
}
html.visual-v2 .float-panel .stat-privacy-note {
  margin: 12px 0 0;
  padding: 10px 12px;
  border: 1px solid var(--divider);
  border-radius: var(--r-3);
  background: color-mix(in oklch, var(--bg-panel) 88%, transparent);
  color: var(--ink-2);
  font-size: 12px;
}
html.visual-v2 .float-panel.float-data .stat-summary table {
  width: 100%;
  border-collapse: collapse;
}
html.visual-v2 .float-panel.float-data .stat-summary td {
  padding: 4px 0;
  border-bottom: 1px solid var(--divider);
}
html.visual-v2 .float-panel.float-data .stat-summary td:first-child {
  color: var(--ink-3);
  padding-right: 12px;
}
html.visual-v2 .float-panel.float-data .stat-run-btn {
  width: 100%;
  min-height: 36px;
  margin-top: auto;
  border: 0;
  border-radius: var(--r-3);
  background: var(--brand);
  color: #fff;
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--dur-2) var(--ease);
}
html.visual-v2 .float-panel.float-data .stat-run-btn:hover {
  background: var(--brand-hover);
}

/* =========== Conv-trail (recent bubbles above cmdbar) =========== */
html.visual-v2 .conv-trail {
  position: absolute;
  bottom: 160px; left: 50%;
  transform: translateX(-50%);
  width: min(680px, calc(100% - 140px));
  max-height: 220px;
  z-index: 15;
  pointer-events: none;
  display: flex; flex-direction: column; align-items: center;
  overflow: hidden;
  transition: max-height var(--dur-3) var(--ease), background var(--dur-2) var(--ease),
              border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}
html.visual-v2 .conv-trail .thread {
  display: flex; flex-direction: column; gap: 10px;
  padding: 12px 12px 4px;
  width: 100%;
  align-items: center;
}
html.visual-v2 .conv-trail .bubble,
html.visual-v2 .conv-trail .thinking {
  pointer-events: auto;
  box-shadow: var(--shadow-2);
  animation: bubble-in 400ms var(--ease-pop) both;
}
@keyframes bubble-in {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}
/* Collapsed — show only last 3 bubbles */
html.visual-v2 .conv-trail:not(.expanded) .thread > :nth-last-child(n+4) {
  display: none;
}

/* Expanded history panel */
html.visual-v2 .conv-trail.expanded {
  max-height: calc(100vh - var(--nav-h) - 140px);
  width: min(820px, calc(100% - 56px));
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-4);
  box-shadow: var(--shadow-4);
  pointer-events: auto;
  overflow-y: auto;
  z-index: 25;
}
html.visual-v2 .conv-trail.expanded .thread > * { display: block; }
html.visual-v2 .conv-trail:not(.expanded) .thread > *:last-child {
  border: 1px solid var(--glass-bd);
}

html.visual-v2 .conv-trail .bubble {
  font-size: 13px; line-height: 1.55;
  max-width: 88%; padding: 8px 12px;
  border-radius: var(--r-3);
}
html.visual-v2 .conv-trail .chat-msg {
  font-size: 13px;
  line-height: 1.55;
  max-width: 88%;
  padding: 8px 12px;
  border-radius: var(--r-3);
  word-wrap: break-word;
  overflow-wrap: break-word;
  box-shadow: var(--shadow-2);
  animation: bubble-in 400ms var(--ease-pop) both;
}
html.visual-v2 .conv-trail .bubble.user,
html.visual-v2 .conv-trail .chat-msg.user {
  align-self: flex-end;
  background: var(--bg-soft); color: var(--ink-1);
  border-radius: var(--r-3) var(--r-3) 2px var(--r-3);
}
html.visual-v2 .conv-trail .bubble.assistant,
html.visual-v2 .conv-trail .chat-msg.assistant {
  align-self: flex-start;
  background: color-mix(in oklch, var(--accent-violet) 8%, var(--bg-panel));
  color: var(--ink-1);
  border: 1px solid color-mix(in oklch, var(--accent-violet) 24%, transparent);
  border-radius: var(--r-3) var(--r-3) var(--r-3) 2px;
}
html.visual-v2 .conv-trail .thinking-bubble {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--ink-3);
}
html.visual-v2 .conv-trail .thinking-dots {
  display: inline-flex;
  gap: 3px;
}
html.visual-v2 .conv-trail .thinking-dots span {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent-violet);
  animation: tb 1.2s ease-in-out infinite;
}
html.visual-v2 .conv-trail .thinking-dots span:nth-child(2) { animation-delay: .15s; }
html.visual-v2 .conv-trail .thinking-dots span:nth-child(3) { animation-delay: .3s; }
html.visual-v2 .conv-trail .hook-chips[hidden] { display: none !important; }
html.visual-v2 .conv-trail .tool-status-bubble {
  color: var(--ink-3);
  font-size: 12px;
  padding: 6px 14px;
  animation: pulse-text 1.5s ease-in-out infinite;
}

/* =========== Bottom cmdbar =========== */
html.visual-v2 .v2-cmdbar {
  position: absolute;
  bottom: 20px; left: 50%; transform: translateX(-50%);
  width: min(720px, calc(100% - 40px));
  z-index: 22;
  margin: 0;
  display: flex; flex-direction: column; align-items: center; gap: 10px;
}
html.visual-v2 .v2-cmdbar .cmdbar {
  display: flex; align-items: center; gap: 6px;
  width: 100%;
  height: 52px; padding: 5px 7px 5px 18px;
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-pill);
  box-shadow: var(--shadow-3);
  transition: border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}
html.visual-v2 .v2-cmdbar .cmdbar:focus-within {
  border-color: color-mix(in oklch, var(--accent-cyan) 70%, transparent);
  box-shadow: var(--shadow-glow-cyan);
}
html.visual-v2 .v2-cmdbar .cmd-input {
  flex: 1; border: none; background: transparent; outline: none;
  font: inherit; font-size: 15px; color: var(--ink-1);
  min-width: 0;
}
html.visual-v2 .v2-cmdbar .cmd-input::placeholder { color: var(--ink-4); }
html.visual-v2 .v2-cmdbar .icon-btn { width: 36px; height: 36px; flex-shrink: 0; }
html.visual-v2 .v2-cmdbar .kbd-row {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  margin-right: 2px;
  color: var(--ink-4);
}

/* Hold-to-Talk button sits inline in cmdbar when voice mode active */
html.visual-v2 .v2-cmdbar .hold-to-talk-btn {
  border: 1px solid var(--border);
  background: var(--bg-panel); color: var(--ink-2);
  font: inherit; font-size: 12px; font-weight: 500;
  padding: 7px 14px; border-radius: var(--r-pill);
  cursor: pointer;
  display: none; /* revealed when voice mode is active */
  transition: all var(--dur-2) var(--ease);
}
html.visual-v2 .v2-cmdbar .hold-to-talk-btn:hover { background: var(--bg-soft); }
html.visual-v2 body.voice-mode .v2-cmdbar .hold-to-talk-btn { display: inline-block; }

/* Hook chips row below cmdbar (shown on landing / fresh chat) */
html.visual-v2 .v2-cmdbar .cmd-chips {
  display: flex; gap: 6px; flex-wrap: wrap; justify-content: center;
  width: 100%;
}
html.visual-v2 .v2-cmdbar .cmd-chips:empty { display: none; }
html.visual-v2 .v2-cmdbar .cmd-chips .chip,
html.visual-v2 .v2-cmdbar .cmd-chips .hook-chip {
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border);
  color: var(--ink-2);
  padding: 5px 12px;
  border-radius: var(--r-pill);
  font-size: 12px; font-weight: 500;
  cursor: pointer;
  transition: all var(--dur-2) var(--ease);
}
html.visual-v2 .v2-cmdbar .cmd-chips .chip:hover,
html.visual-v2 .v2-cmdbar .cmd-chips .hook-chip:hover {
  color: var(--brand); border-color: var(--brand); background: var(--bg-tint);
}

html.visual-v2 .hook-highlight {
  position: relative;
  border-radius: var(--r-2);
  outline: 2px solid color-mix(in oklch, var(--accent-cyan) 62%, white 8%);
  outline-offset: 3px;
  box-shadow:
    0 0 0 1px color-mix(in oklch, var(--accent-cyan) 38%, transparent),
    0 14px 34px color-mix(in oklch, var(--accent-cyan) 22%, transparent),
    0 0 28px color-mix(in oklch, var(--accent-cyan) 18%, transparent);
  animation: v2-hook-glow 1s ease-in-out 2;
}
html.visual-v2 .float-panel .func-input-row.hook-highlight {
  border-color: color-mix(in oklch, var(--accent-cyan) 58%, var(--border));
  background: color-mix(in oklch, var(--accent-cyan) 10%, var(--bg-panel));
}
html.visual-v2 .v2-cmdbar .cmdbar.hook-highlight,
html.visual-v2 .chat-input-row.hook-highlight {
  border-color: color-mix(in oklch, var(--accent-cyan) 68%, var(--glass-bd));
  box-shadow:
    0 0 0 1px color-mix(in oklch, var(--accent-cyan) 38%, transparent),
    0 18px 40px color-mix(in oklch, var(--accent-cyan) 22%, transparent),
    0 0 32px color-mix(in oklch, var(--accent-cyan) 20%, transparent);
}
html.visual-v2 .hook-chat-hint {
  position: absolute;
  bottom: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%);
  padding: 7px 12px;
  border-radius: var(--r-2);
  border: 1px solid color-mix(in oklch, var(--accent-cyan) 45%, transparent);
  background: color-mix(in oklch, var(--bg-panel) 72%, white 8%);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  color: var(--ink-1);
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
  pointer-events: none;
  z-index: 26;
  box-shadow: var(--shadow-2);
  transition: opacity 0.3s;
}

@keyframes v2-hook-glow {
  0%, 100% {
    box-shadow:
      0 0 0 1px color-mix(in oklch, var(--accent-cyan) 38%, transparent),
      0 14px 34px color-mix(in oklch, var(--accent-cyan) 22%, transparent),
      0 0 28px color-mix(in oklch, var(--accent-cyan) 18%, transparent);
  }
  50% {
    box-shadow:
      0 0 0 1px color-mix(in oklch, var(--accent-cyan) 54%, transparent),
      0 18px 42px color-mix(in oklch, var(--accent-cyan) 30%, transparent),
      0 0 36px color-mix(in oklch, var(--accent-cyan) 24%, transparent);
  }
}

/* =========== AI orb in cmdbar (expressive state indicator) =========== */
html.visual-v2 .ai-orb {
  width: 22px; height: 22px;
  position: relative;
  flex-shrink: 0;
  display: inline-block;
  margin-right: 4px;
}
html.visual-v2 .ai-orb-inner {
  position: absolute; inset: 4px;
  border-radius: 50%;
  background: conic-gradient(from 210deg, var(--accent-cyan), var(--brand), var(--accent-violet), var(--accent-cyan));
  animation: orb-rot 6s linear infinite, orb-breathe 2.4s var(--ease) infinite;
  box-shadow: 0 0 10px color-mix(in oklch, var(--accent-cyan) 50%, transparent);
}
html.visual-v2 .ai-orb-ring {
  position: absolute; inset: 0;
  border-radius: 50%;
  border: 1.5px solid color-mix(in oklch, var(--accent-cyan) 40%, transparent);
}
html.visual-v2 .ai-orb.recording .ai-orb-inner {
  animation: orb-rot 1.8s linear infinite, orb-breathe 0.8s var(--ease) infinite;
  background: conic-gradient(from 210deg, var(--accent-cyan), #fff, var(--accent-cyan));
}
html.visual-v2 .ai-orb.recording .ai-orb-ring {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 4px color-mix(in oklch, var(--accent-cyan) 20%, transparent);
}
html.visual-v2 .ai-orb.thinking .ai-orb-inner {
  background: conic-gradient(from 210deg, var(--accent-violet), var(--brand), var(--accent-violet));
  animation: orb-rot 1.2s linear infinite, orb-breathe 1.2s var(--ease) infinite;
}
@keyframes orb-rot     { to { transform: rotate(360deg); } }
@keyframes orb-breathe { 0%,100% { filter: brightness(1); } 50% { filter: brightness(1.25); } }

/* Send button — round primary */
html.visual-v2 .v2-cmdbar .chat-send-btn {
  width: 38px; height: 38px;
  background: var(--brand); color: #fff;
  border: none; border-radius: 50%;
  cursor: pointer; font-size: 16px;
  display: inline-flex; align-items: center; justify-content: center;
  transition: background var(--dur-2) var(--ease), transform var(--dur-2) var(--ease);
}
html.visual-v2 .v2-cmdbar .chat-send-btn:hover { background: var(--brand-hover); }
html.visual-v2 .v2-cmdbar .chat-send-btn:active { transform: translateY(1px); }

/* Mic/camera icon-buttons inside cmdbar */
html.visual-v2 .v2-cmdbar .mic-btn,
html.visual-v2 .v2-cmdbar .camera-btn {
  width: 36px; height: 36px; border-radius: 50%;
  background: transparent; border: 1px solid transparent;
  color: var(--ink-2); cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: all var(--dur-2) var(--ease);
  padding: 0;
}
html.visual-v2 .v2-cmdbar .mic-btn:hover,
html.visual-v2 .v2-cmdbar .camera-btn:hover { background: var(--bg-soft); color: var(--ink-1); }
html.visual-v2 .v2-cmdbar .mic-btn svg,
html.visual-v2 .v2-cmdbar .camera-btn svg {
  width: 16px; height: 16px;
  display: block;
  fill: currentColor;
}
html.visual-v2 .v2-cmdbar .mic-btn.recording {
  background: color-mix(in oklch, var(--accent-error) 12%, transparent);
  color: var(--accent-error);
  box-shadow: 0 0 0 3px color-mix(in oklch, var(--accent-error) 25%, transparent);
  animation: mic-pulse 1.5s ease-in-out infinite;
}
@keyframes mic-pulse {
  0%, 100% { box-shadow: 0 0 0 3px color-mix(in oklch, var(--accent-error) 25%, transparent); }
  50%      { box-shadow: 0 0 0 6px color-mix(in oklch, var(--accent-error) 10%, transparent); }
}
@keyframes pulse-text {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

html.visual-v2 .graph-container.tool-active {
  box-shadow: inset 0 0 0 2px color-mix(in oklch, var(--brand) 36%, transparent);
  animation: pulse-border 1.5s ease-in-out infinite;
}
@keyframes pulse-border {
  0%, 100% { box-shadow: inset 0 0 0 2px color-mix(in oklch, var(--brand) 20%, transparent); }
  50% { box-shadow: inset 0 0 0 2px color-mix(in oklch, var(--brand) 65%, transparent); }
}
html.visual-v2 .share-toast {
  position: absolute;
  right: 18px;
  bottom: 92px;
  z-index: 28;
  padding: 8px 14px;
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-pill);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  color: var(--ink-1);
  font-size: 12px;
  box-shadow: var(--shadow-3);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-2) var(--ease);
}
html.visual-v2 .share-toast.show { opacity: 1; }

/* =========== Coord tooltip (controls.js creates this dynamically) =========== */
html.visual-v2 .coord-tooltip {
  position: absolute; pointer-events: none;
  padding: 3px 8px;
  font-family: var(--font-mono); font-size: 11px;
  color: var(--ink-2);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-2);
  opacity: 0; transition: opacity var(--dur-1) var(--ease);
  z-index: 10;
}

/* =========== Show / calculator overlays on v2 canvas =========== */
html.visual-v2 .show-controller {
  position: absolute;
  bottom: 82px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 6px;
  border-radius: var(--r-pill);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-bd);
  box-shadow: var(--shadow-3);
  font-family: var(--font-sans);
  z-index: 24;
}
html.visual-v2 .show-btn {
  width: 28px; height: 28px;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--ink-2);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
html.visual-v2 .show-btn:hover { background: var(--bg-soft); color: var(--ink-1); }
html.visual-v2 .show-counter {
  min-width: 42px;
  text-align: center;
  font-size: 12px;
  color: var(--ink-3);
  font-variant-numeric: tabular-nums;
}
html.visual-v2 .show-note {
  position: absolute;
  top: 76px;
  left: 20px;
  max-width: 360px;
  max-height: 168px;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 14px 16px;
  border-radius: var(--r-4);
  background: var(--mt-note-bg, var(--glass-bg-hi));
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--mt-note-border, var(--glass-bd));
  box-shadow: var(--shadow-3);
  color: var(--mt-note-text, var(--ink-1));
  font-size: 13px;
  font-family: var(--font-sans);
  font-weight: 500;
  line-height: 1.55;
  white-space: pre-line;
  opacity: 0;
  transition: opacity var(--dur-2) var(--ease);
  z-index: 23;
}
html.visual-v2 .show-note::before {
  content: '';
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  border-radius: inherit;
  background: linear-gradient(90deg, rgba(255,255,255,0.42), rgba(255,255,255,0));
  pointer-events: none;
}
html.visual-v2 .show-note::after { content: none; }
html.visual-v2 .show-note.visible { opacity: 1; }
html.visual-v2 .show-note.calc-panel {
  max-height: none;
  overflow: visible;
}
html.visual-v2[data-plot-style="terminal"] .show-note {
  font-family: var(--font-mono);
  letter-spacing: 0.01em;
}
html.visual-v2[data-plot-style="science"] .show-note,
html.visual-v2[data-plot-style="finance"] .show-note {
  font-family: Georgia, 'Times New Roman', serif;
}
html.visual-v2[data-plot-style="wallstreet"] .show-note {
  letter-spacing: 0.01em;
}
html.visual-v2[data-plot-style="terminal"] .show-note,
html.visual-v2[data-plot-style="science"] .show-note,
html.visual-v2[data-plot-style="finance"] .show-note,
html.visual-v2[data-plot-style="wallstreet"] .show-note {
  background: var(--mt-note-bg, var(--glass-bg-hi));
  border-color: var(--mt-note-border, var(--glass-bd));
  color: var(--mt-note-text, var(--ink-1));
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  box-shadow: 0 8px 22px rgba(9,14,30,0.12);
}
html.visual-v2[data-plot-style="terminal"] .show-note::before,
html.visual-v2[data-plot-style="science"] .show-note::before,
html.visual-v2[data-plot-style="finance"] .show-note::before,
html.visual-v2[data-plot-style="wallstreet"] .show-note::before {
  content: none;
}
html.visual-v2 .param-slider-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 0 0 22px;
  font-size: 13px;
}
html.visual-v2 .track-slider-row { padding-left: 0; }
html.visual-v2 .param-play-btn {
  width: 28px;
  height: 28px;
  min-width: 28px;
  border: 1px solid transparent;
  border-radius: 999px;
  background:
    linear-gradient(180deg, color-mix(in oklab, #fff 26%, var(--glass-bg-hi)), color-mix(in oklab, var(--glass-bg) 92%, transparent));
  color: var(--ink-2);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  letter-spacing: -1px;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.42),
    0 6px 16px rgba(9,14,30,0.10);
  transition: transform var(--dur-2) var(--ease), background var(--dur-2) var(--ease), color var(--dur-2) var(--ease), border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}
html.visual-v2 .param-play-btn:hover {
  background: color-mix(in oklab, var(--bg-soft) 82%, transparent);
  color: var(--ink-1);
  border-color: var(--divider);
}
html.visual-v2 .param-play-btn:active { transform: translateY(1px); }
html.visual-v2 .param-play-btn.playing {
  background:
    radial-gradient(circle at 32% 28%, rgba(255,255,255,0.36), transparent 44%),
    linear-gradient(135deg, var(--accent-cyan), color-mix(in oklab, var(--accent-violet) 76%, var(--brand)));
  color: #fff;
  border-color: color-mix(in oklab, var(--accent-cyan) 34%, transparent);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.28),
    0 10px 22px color-mix(in oklab, var(--accent-violet) 18%, transparent);
}
html.visual-v2 .param-label {
  min-width: 18px;
  font-weight: 600;
  color: var(--ink-2);
  font-family: var(--font-math);
  font-style: italic;
  font-size: 13px;
}
html.visual-v2 .param-slider {
  flex: 1;
  max-width: 180px;
  height: 4px;
  accent-color: var(--brand);
  cursor: pointer;
}
html.visual-v2 .param-value {
  min-width: 40px;
  text-align: right;
  font-size: 12px;
  color: var(--ink-3);
  font-variant-numeric: tabular-nums;
}
html.visual-v2 .calc-inputs { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; }
html.visual-v2 .calc-row { display: flex; gap: 12px; align-items: center; flex-basis: 100%; }
html.visual-v2 .calc-row-label,
html.visual-v2 .calc-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--mt-note-text, var(--ink-2));
  display: inline-flex;
  align-items: center;
  gap: 5px;
}
html.visual-v2 .calc-input,
html.visual-v2 .calc-unit,
html.visual-v2 .calc-color {
  padding: 4px 7px;
  border: 1px solid color-mix(in oklab, var(--mt-note-border, var(--border)) 28%, transparent);
  border-radius: var(--r-1);
  background: color-mix(in oklab, var(--mt-note-bg, var(--bg-sunk)) 86%, var(--mt-canvas-bg, #fff) 14%);
  color: var(--mt-note-text, var(--ink-1));
  font: inherit;
  font-size: 12px;
}
html.visual-v2 .calc-input::placeholder { color: color-mix(in oklab, var(--mt-note-text, var(--ink-3)) 56%, transparent); }
html.visual-v2 .calc-input { width: 62px; }
html.visual-v2 .calc-result {
  margin-top: 8px;
  font-size: 13px;
  color: var(--mt-note-text, var(--ink-1));
}
html.visual-v2 .overview-btn {
  position: absolute;
  left: 20px;
  bottom: 84px;
  border: 1px solid var(--glass-bd);
  border-radius: var(--r-pill);
  background: var(--glass-bg-hi);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  color: var(--ink-2);
  box-shadow: var(--shadow-2);
  padding: 7px 12px;
  font: inherit;
  font-size: 12px;
  cursor: pointer;
  z-index: 24;
}
html.visual-v2 .overview-btn:hover { color: var(--ink-1); background: var(--bg-panel); }

/* =========== Responsive =========== */
@media (max-width: 1100px) {
  html.visual-v2 .float-panel.float-objects,
  html.visual-v2 .float-panel.float-data,
  html.visual-v2 .float-panel.float-lesson-info {
    width: 320px;
  }
  html.visual-v2 .float-panel.float-lesson-info {
    height: min(34vh, 280px);
  }
  html.visual-v2 .float-panel.float-faq,
  html.visual-v2 .float-panel.float-suggested { width: 320px; }
  html.visual-v2 .float-top { left: 12px; right: 12px; }
  html.visual-v2 .float-top .nav-live { display: none; }
  html.visual-v2 .conv-trail { width: min(620px, calc(100% - 120px)); }
}
@media (max-width: 768px) {
  html.visual-v2 .float-panel.float-objects,
  html.visual-v2 .float-panel.float-data {
    top: auto; bottom: 120px; left: 12px; right: 12px;
    width: auto;
    min-height: 280px;
    height: 44vh;
    max-height: 44vh;
  }
  html.visual-v2 .float-panel.float-lesson-info {
    top: auto; bottom: 120px; left: 12px; right: 12px;
    width: auto;
    min-height: 220px;
    height: 34vh;
    max-height: 34vh;
  }
  html.visual-v2 .float-panel.float-faq,
  html.visual-v2 .float-panel.float-suggested {
    top: auto; bottom: 120px; left: 12px; right: 12px;
    width: auto;
    min-height: 280px;
    height: 44vh;
    max-height: 44vh;
  }
  html.visual-v2 .conv-trail {
    bottom: calc(120px + 44vh + 12px);
    max-height: 26vh;
    width: calc(100% - 24px);
  }
  html.visual-v2 .conv-trail.expanded { max-height: calc(100vh - 120px - 44vh - 44px); }
  html.visual-v2 .v2-cmdbar { bottom: 16px; width: calc(100% - 24px); }
  html.visual-v2 .float-tools { top: 76px; right: 12px; }
  html.visual-v2 .float-top { height: 44px; padding: 0 8px 0 12px; }
  html.visual-v2 .float-top .tab-group { padding: 2px; }
  html.visual-v2 .float-top .tab { padding: 5px 10px; font-size: 12px; }
  html.visual-v2 .show-note { left: 12px; right: 12px; max-width: none; }
  html.visual-v2 .show-controller { bottom: 76px; }
}
@media (max-width: 480px) {
  html.visual-v2 .v2-cmdbar .hold-to-talk-btn { display: none !important; }
  html.visual-v2 .v2-cmdbar .cmd-input { font-size: 13px; }
  html.visual-v2 .v2-cmdbar .kbd-row { display: none; }
  html.visual-v2 .float-top .lang-select-v2 { display: none; }
  html.visual-v2 .float-top .nav-slogan { display: none; }
  html.visual-v2 .float-top .tab-group { overflow-x: auto; scrollbar-width: none; max-width: 50vw; }
  html.visual-v2 .float-top .panel-switcher { gap: 2px; }
}
