/**
 * einstein/styles.css — Landing page design
 * References: tesseract/styles.css, nitroxhq.github.io/home.css
 * Theme-aware via light-dark(), synchronized with theme.js
 */

@font-face {
  font-family: 'Inter';
  font-weight: 400;
  src: url('assets/fonts/inter/InterVariable.woff2') format('woff2');
  font-display: swap;
}
@font-face {
  font-family: 'EB Garamond';
  font-weight: 400;
  src: url('assets/fonts/eb-garamond/EBGaramond-VariableFont_wght.woff2') format('woff2');
  font-display: swap;
}

:root {
  --nitrox-blue: #3232ff;
  --tess-purple: #a161ea;
  --tess-violet: #c897ff;
  --tess-ink: #0b0b10;
  --tess-obsidian: #0f0f0f;
  --tess-lavender: #f4effc;

  color-scheme: light dark;

  --canvas: light-dark(var(--tess-lavender), var(--tess-obsidian));
  --surface: light-dark(rgba(255,255,255,0.78), rgba(20,20,20,0.75));
  --text: light-dark(var(--tess-ink), #ffffff);
  --text-soft: light-dark(rgba(11,11,16,0.55), rgba(255,255,255,0.65));
  --text-meta: light-dark(rgba(11,11,16,0.45), rgba(255,255,255,0.45));
  --line: light-dark(rgba(11,11,16,0.12), rgba(255,255,255,0.12));

  --accent: light-dark(var(--tess-purple), var(--nitrox-blue));
  --accent-strong: light-dark(#6d28d9, #5a5aff);

  /* nav chrome */
  --nav-bg: light-dark(rgba(255,255,255,0.92), rgba(23,23,26,0.82));
  --nav-ink: light-dark(var(--tess-ink), var(--tess-lavender));
  --nav-line: light-dark(rgba(11,11,16,0.10), rgba(255,255,255,0.12));
  --nav-hover-bg: light-dark(rgba(11,11,16,0.06), rgba(255,255,255,0.08));
  --nav-shadow: light-dark(rgba(11,11,16,0.14), rgba(0,0,0,0.55));
  --nav-track-bg: light-dark(rgba(11,11,16,0.05), rgba(255,255,255,0.07));
  --nav-active-bg: light-dark(rgba(161,97,234,0.13), rgba(161,97,234,0.22));

  --font-sans: 'Inter', system-ui, sans-serif;
  --font-serif: 'EB Garamond', Georgia, serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--canvas);
  color: var(--text);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ============ NAV ============ */
#nav-placeholder {
  position: sticky; top: 16px; z-index: 100;
  display: flex; justify-content: center; padding: 0 1rem;
}

.nitrox-nav {
  display: flex; align-items: center; justify-content: space-between;
  gap: 2rem; padding: 8px 18px;
  width: max-content; max-width: calc(100vw - 32px);
  background-color: var(--nav-bg); color: var(--nav-ink);
  border-radius: 100vmax; box-shadow: 0 8px 20px var(--nav-shadow);
  -webkit-backdrop-filter: blur(14px) saturate(1.2);
  backdrop-filter: blur(14px) saturate(1.2);
  font-family: var(--font-sans); font-weight: 600;
}

.nav-brand-group { display: flex; align-items: center; gap: 4px; }

.nav-brand {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 4px; margin: -4px; border-radius: 8px;
  color: inherit; text-decoration: none;
  transition: color 0.2s ease, transform 0.2s ease;
}
.nav-brand:hover { color: var(--accent); transform: translateY(-1px); }

.nav-logo { font-size: 1.05rem; line-height: 1; }

.nav-brand-text {
  font-size: 1.05rem; font-weight: 600; letter-spacing: -0.01em;
}

.nitrox-brand {
  display: inline-flex; align-items: center; gap: 6px;
  margin-left: 6px; padding: 2px 2px 2px 12px;
  border-left: 1px solid var(--nav-line);
  color: var(--nav-ink); text-decoration: none; opacity: 0.72;
  transition: opacity 0.2s ease, transform 0.2s ease;
}
.nitrox-brand:hover { opacity: 1; transform: translateY(-1px); }

.nitrox-logo {
  display: block; width: 13px; height: 15px; flex: none;
}

.nitrox-brand-text { font-size: 0.9rem; font-weight: 600; }

.nav-menu ul {
  display: flex; align-items: center; gap: 0.15rem;
  list-style: none; margin: 0; padding: 0;
}

.nav-link {
  display: inline-block; text-decoration: none; color: var(--nav-ink);
  font-size: 0.92rem; font-weight: 600; white-space: nowrap;
  padding: 0.35rem 0.7rem; border-radius: 999px;
  transition: background-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
}
.nav-link:hover { background-color: var(--nav-hover-bg); transform: translateY(-1px); }
.nav-link.active { color: var(--accent); background-color: var(--nav-active-bg); }
.nav-github { opacity: 0.65; }
.nav-github:hover { opacity: 1; }

.nav-actions { display: flex; align-items: center; gap: 6px; }

.theme-toggle-btn {
  display: inline-flex; align-items: center; gap: 5px;
  background: transparent; border: 0; border-radius: 999px;
  padding: 5px 9px; color: var(--nav-ink); cursor: pointer;
  font-family: var(--font-sans); font-weight: 600; font-size: 0.78rem;
  letter-spacing: 0.02em; opacity: 0.75;
  transition: background-color 0.2s ease, opacity 0.2s ease;
}
.theme-toggle-btn:hover { background-color: var(--nav-hover-bg); opacity: 1; }
.theme-label { font-size: 0.75rem; }
.theme-icon { display: none; }
.theme-toggle-btn[data-active-theme="dark"] .theme-icon-dark,
.theme-toggle-btn[data-active-theme="light"] .theme-icon-light,
.theme-toggle-btn[data-active-theme="device"] .theme-icon-device { display: inline-block; }

.nav-hamburger {
  display: none; flex-direction: column; gap: 4px; width: 34px; height: 34px;
  justify-content: center; align-items: center; background: transparent; border: 0;
  border-radius: 999px; color: var(--nav-ink); cursor: pointer;
}
.nav-hamburger:hover { background-color: var(--nav-hover-bg); }
.nav-hamburger-line {
  display: block; width: 17px; height: 2px; border-radius: 2px; background: currentColor;
  transition: transform 0.2s ease, opacity 0.15s ease;
}
.nav-hamburger.active .nav-hamburger-line:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-hamburger.active .nav-hamburger-line:nth-child(2) { opacity: 0; }
.nav-hamburger.active .nav-hamburger-line:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

@media (max-width: 860px) {
  .nitrox-nav {
    width: auto; max-width: none; margin: 0 0.5rem; padding: 8px 12px;
    flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1rem;
  }
  .nitrox-nav:has(.nav-menu-open) { border-radius: 20px; }
  .nav-menu {
    display: none; order: 3; flex-basis: 100%; width: 100%;
    border-top: 1px solid var(--nav-line); padding-top: 6px;
  }
  .nav-menu.nav-menu-open { display: block; }
  .nav-menu ul { flex-direction: column; align-items: stretch; gap: 0; }
  .nav-link { display: block; padding: 0.65rem 0.6rem; border-radius: 10px; }
  .nav-hamburger { display: inline-flex; }
  .nitrox-brand-text { display: none; }
}

/* ============ HERO ============ */
.hero {
  position: relative;
  overflow: hidden;
  min-height: 78vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 7rem 2rem 4rem;
  margin-bottom: 0;
}

.hero-glow {
  position: absolute;
  top: 50%; left: 50%;
  width: 40vw; height: 40vw;
  background: radial-gradient(circle, rgba(161,97,234,0.10) 0%, rgba(161,97,234,0) 70%);
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 0;
}

.hero-inner { position: relative; z-index: 1; max-width: 780px; margin: 0 auto; }

.hero h1 {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(3rem, 6.5vw, 5.5rem);
  line-height: 0.95;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  color: var(--text);
}

.hero h1 em {
  font-style: italic;
  color: var(--accent);
}

.hero-lede {
  font-family: var(--font-sans);
  font-size: clamp(1.05rem, 1.5vw, 1.35rem);
  color: var(--text-soft);
  max-width: 540px;
  margin: 0 auto 3rem;
  line-height: 1.6;
}

.hero-actions {
  display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap;
}

.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.85rem 1.6rem; border-radius: 999px;
  font-family: var(--font-sans); font-weight: 600; font-size: 0.95rem;
  text-decoration: none; border: 1.5px solid transparent;
  transition: transform 0.12s ease, background 0.2s ease, border-color 0.2s ease;
}

.btn-solid {
  background: var(--accent); color: #fff; border-color: var(--accent);
}
.btn-solid:hover { background: var(--accent-strong); border-color: var(--accent-strong); transform: translateY(-2px); }

.btn-ghost {
  background: transparent; color: var(--text); border-color: var(--line);
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

/* ============ SECTIONS ============ */
.section { padding: 4.5rem 2rem; max-width: 1100px; margin: 0 auto; }

.section-label {
  font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--text-meta); margin-bottom: 0.75rem; font-weight: 600;
}

.section h2 {
  font-family: var(--font-serif); font-weight: 400;
  font-size: clamp(2rem, 4vw, 3.2rem); line-height: 1.1;
  letter-spacing: -0.02em; margin-bottom: 1rem;
}

.section-lede {
  color: var(--text-soft); font-size: 1.05rem; max-width: 560px; line-height: 1.55;
  margin-bottom: 2rem;
}

/* section headings and ledes are centred; the card grids keep their own
   left alignment so the copy inside each card stays readable */
.section > div > .section-label,
.section > div > h2,
.section > div > .section-lede {
  text-align: center; margin-left: auto; margin-right: auto;
}
.section > div > .section-lede { margin-bottom: 2rem; }
.bento-grid, .docs-ref, .lab-preview { text-align: left; }

/* ============ FEATURES / BENTO ============ */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}
@media (max-width: 720px) { .bento-grid { grid-template-columns: 1fr; } }

.bento-card {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 2rem 2rem 1.75rem;
  background: var(--surface);
  transition: border-color 0.2s ease, transform 0.15s ease;
  text-decoration: none; color: inherit; display: block;
}

.bento-card:hover { border-color: var(--accent); transform: translateY(-3px); }

.bento-card h3 {
  font-family: var(--font-serif); font-weight: 400; font-size: 1.35rem;
  margin-bottom: 0.5rem; letter-spacing: -0.01em;
}

.bento-card p { color: var(--text-soft); font-size: 0.92rem; line-height: 1.5; }

.bento-card .card-tag {
  display: inline-block; margin-top: 1rem;
  font-size: 0.7rem; font-weight: 600; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--accent);
}

/* Wide card for what-if */
.bento-wide { grid-column: span 2; }
@media (max-width: 720px) { .bento-wide { grid-column: span 1; } }

/* ============ WHAT-IF LAB TEASER ============ */
.lab-preview {
  border: 1px solid var(--line); border-radius: 20px;
  padding: 2.5rem; background: var(--surface);
  margin-top: 2rem;
}

.lab-preview h3 {
  font-family: var(--font-serif); font-size: 1.6rem; margin-bottom: 0.25rem;
}

.lab-preview > p { color: var(--text-soft); margin-bottom: 2rem; }

.lab-grid {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  gap: 2.5rem; align-items: start;
}
@media (max-width: 760px) { .lab-grid { grid-template-columns: 1fr; gap: 1.75rem; } }

/* editable category table */
.lab-table { width: 100%; border-collapse: collapse; font-size: 0.85rem; }
.lab-table th {
  text-align: left; font-size: 0.68rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.07em; color: var(--text-meta);
  padding: 0 0.3rem 0.5rem;
}
.lab-table td { padding: 0.45rem 0.3rem; border-top: 1px solid var(--line); }
.lab-table tr:last-child td { color: var(--text-meta); }
.lab-table .cat-name { font-weight: 600; color: var(--text); }
.lab-table input {
  width: 100%; max-width: 4.5rem;
  background: var(--canvas); border: 1px solid var(--line); border-radius: 6px;
  padding: 0.28rem 0.4rem; color: var(--text);
  font-family: var(--font-sans); font-size: 0.82rem;
}
.lab-table input:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.lab-sim { display: flex; flex-direction: column; gap: 1.5rem; }

.lab-sim label { display: block; font-size: 0.68rem; font-weight: 600; letter-spacing: 0.07em; text-transform: uppercase; color: var(--text-meta); margin-bottom: 0.5rem; }

.lab-sim input[type="range"] { width: 100%; accent-color: var(--accent); }

.sim-slider-value { margin-top: 0.35rem; font-size: 0.8rem; color: var(--text-meta); }

.sim-outputs { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; }
@media (max-width: 520px) { .sim-outputs { grid-template-columns: 1fr; } }

.sim-output {
  font-family: var(--font-serif); font-size: 1.8rem; color: var(--text); line-height: 1.2;
}

.lab-footnote {
  margin: 0; font-size: 0.78rem; color: var(--text-meta); line-height: 1.5;
  border-top: 1px solid var(--line); padding-top: 0.9rem;
}

.lab-badge {
  display: inline-block; margin-left: 0.5rem; padding: 0.15rem 0.55rem;
  font-family: var(--font-sans); font-size: 0.62rem; font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase; vertical-align: middle;
  color: var(--accent); background: var(--nav-active-bg);
  border-radius: 999px;
}

/* ============ DOCS REFERENCE ============ */
.docs-ref {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1.25rem; margin-top: 2rem;
}

.doc-card {
  border: 1px solid var(--line); border-radius: 14px; padding: 1.25rem 1.25rem 1rem;
  background: var(--surface); text-decoration: none; color: inherit;
  transition: border-color 0.2s ease, transform 0.15s ease;
}

.doc-card:hover { border-color: var(--accent); transform: translateY(-3px); }

.doc-card h4 {
  font-family: var(--font-serif); font-size: 1.1rem; margin-bottom: 0.35rem;
}

.doc-card span { font-size: 0.75rem; color: var(--text-meta); text-transform: uppercase; letter-spacing: 0.06em; font-weight: 600; }

/* ============ FOOTER ============ */
.site-footer {
  border-top: 1px solid var(--line); padding: 2.5rem 2rem; text-align: center;
  color: var(--text-meta); font-size: 0.85rem;
}

.site-footer .footer-brand {
  display: flex; align-items: center; justify-content: center; gap: 0.5rem;
  margin-bottom: 0.75rem; font-weight: 600; color: var(--text);
}

/* ============ CLOSING CTA ============ */
.cta-section { padding: 2rem 2rem 5rem; }
.cta-card {
  border: 1px solid var(--line); border-radius: 24px;
  padding: 3rem 2rem; text-align: center;
  background:
    radial-gradient(120% 130% at 50% 0%, var(--nav-active-bg) 0%, transparent 62%),
    var(--surface);
}
.cta-card h2 { margin-bottom: 0.75rem; }
.cta-lede { color: var(--text-soft); max-width: 520px; margin: 0 auto 2rem; }

/* ============ ABOUT ============ */
.about-hero { min-height: auto; padding: 7rem 2rem 2.5rem; }
.section-lede + .section-lede { margin-top: -1rem; }

/* Responsive */
@media (max-width: 640px) {
  .hero { min-height: auto; padding: 6rem 1.5rem 3rem; }
  .section { padding: 3.5rem 1.25rem; }
  .cta-section { padding: 1rem 1.25rem 4rem; }
  .about-hero { padding: 6rem 1.5rem 2rem; }
}



/* me 10.27.2026 11:38a idk */
.comparison {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin: 1.5rem 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: #131313;
    color: #c9d1d9;
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid #30363d;
  }

  .comparison th,
  .comparison td {
    padding: 12px 16px;
    text-align: left;
    vertical-align: top;
    border-bottom: 1px solid #21262d;
    border-right: 1px solid #21262d;
    font-size: 0.9rem;
    line-height: 1.4;
  }

  .comparison th:last-child,
  .comparison td:last-child {
    border-right: none;
  }

  .comparison tr:last-child td {
    border-bottom: none;
  }

  .comparison thead th {
    background-color: #1e1e1e;
    color: #f0f6fc;
    font-weight: 600;
  }

  /* Highlight the Einstein Column */
  .comparison th:nth-child(5),
  .comparison td:nth-child(5) {
    background-color: rgba(46, 160, 67, 0.08);
  }

  .comparison th:nth-child(5) {
    background-color: rgba(46, 160, 67, 0.18);
    color: #3fb950;
  }

  .comparison td:first-child {
    font-weight: 600;
    color: #f0f6fc;
    background-color: #1e1e1e;
  }

  .comparison a {
    color: #58a6ff;
    text-decoration: none;
  }

  .comparison a:hover {
    text-decoration: underline;
  }
/* ============ APP COMPARISON ============ */
.app-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1.25rem;
  margin-top: 2rem; text-align: left;
}
.app-card {
  border: 1px solid var(--line); border-radius: 20px; padding: 1.75rem 1.5rem;
  background: var(--surface); transition: border-color 0.2s ease, transform 0.15s ease;
}
.app-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.app-card-einstein { border-color: rgba(161,97,234,0.25); background: linear-gradient(135deg, rgba(161,97,234,0.06), var(--surface)); }
.app-kicker {
  font-size: 0.68rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--text-meta); margin-bottom: 0.5rem;
}
.app-card-einstein .app-kicker { color: var(--accent); }
.app-card h3 { font-family: var(--font-serif); font-weight: 400; font-size: 1.2rem; letter-spacing: -0.01em; margin-bottom: 0.7rem; }
.app-what { font-size: 0.9rem; color: var(--text-soft); margin-bottom: 1.1rem; line-height: 1.45; }
.app-facts > div { display: flex; gap: 0.75rem; margin-bottom: 0.6rem; font-size: 0.82rem; line-height: 1.35; }
.app-facts dt { font-weight: 600; color: var(--text); white-space: nowrap; min-width: 4.5rem; }
.app-facts dd { color: var(--text-soft); flex: 1; }
.app-verdict {
  margin-top: 1rem; padding-top: 0.75rem; border-top: 1px solid var(--line);
  font-family: var(--font-serif); font-style: italic; font-size: 1rem; color: var(--text); }

/* ============ DEEP COMPARISON TABLE ============ */
.comparison-scroll { overflow-x: auto; margin: 2rem 0 0.5rem; border-radius: 14px; border: 1px solid var(--line); background: var(--surface); }
.deep-comparison { width: 100%; min-width: 720px; border-collapse: separate; border-spacing: 0; font-size: 0.82rem; }
.deep-comparison th, .deep-comparison td { padding: 0.7rem 0.9rem; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; line-height: 1.35; }
.deep-comparison th { font-weight: 600; color: var(--text); background: var(--canvas); font-size: 0.7rem; letter-spacing: 0.06em; text-transform: uppercase; }
.deep-comparison td { color: var(--text-soft); }
.deep-comparison th.col-einstein, .deep-comparison td.col-einstein { background: rgba(161,97,234,0.08); color: var(--text); }
.deep-comparison th.col-einstein { background: rgba(161,97,234,0.18); color: var(--accent); }
.deep-comparison td.col-einstein { font-weight: 600; }
.deep-comparison th .th-sub { display: block; text-transform: none; letter-spacing: 0; font-weight: 400; color: var(--text-meta); font-size: 0.72rem; }
.comparison-note { font-size: 0.78rem; color: var(--text-meta); margin-top: 0.6rem; }

/* ============ GRADE SIMULATOR — COURSEWORK / FINAL SPLIT ============ */
.lab-split { margin-top: 1.25rem; padding-top: 0.75rem; border-top: 1px solid var(--line); }
.lab-split label { display: block; font-size: 0.72rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; margin-bottom: 0.35rem; color: var(--text-meta); }
.lab-split-row { display: flex; align-items: center; gap: 0.6rem; }
.lab-split-row input { width: 4rem; }
.lab-split-unit { font-size: 0.75rem; color: var(--text-meta); }
.lab-split-help { font-size: 0.78rem; color: var(--text-soft); margin-top: 0.5rem; line-height: 1.45; margin-bottom: 0.25rem; }
.lab-subtotal td { font-weight: 600; color: var(--text); background: rgba(161,97,234,0.05); }
.lab-math { font-size: 0.75rem; color: var(--text-meta); margin-top: 0.75rem; font-family: var(--font-mono, ui-monospace, monospace); letter-spacing: -0.01em; }