/* =============================================================
   Disk Scheduling Algorithms — Visualizer
   Design system & styles
   ============================================================= */

/* ---------- Design tokens ---------- */
:root {
  /* Brand (anchored on the teal used across the charts & disk) */
  --brand-900: #10302b;
  --brand-800: #143430;
  --brand-700: #1c4842;
  --brand-600: #245953;   /* primary */
  --brand-500: #2f716a;
  --brand-400: #3d8b82;
  --brand-300: #63a99c;
  --brand-100: #d8e8e4;
  --brand-050: #eef5f3;

  /* Accents / states */
  --accent:    #f4a261;   /* warm highlight */
  --accent-dk: #e07a3e;
  --coral:     #e63946;   /* current head */
  --success:   #2a9d6f;   /* served */
  --info:      #457b9d;

  /* Neutrals */
  --bg:        #eef2f1;
  --surface:   #ffffff;
  --surface-2: #f6f9f8;
  --text:      #14211f;
  --muted:     #5c6c69;
  --faint:     #8a9995;
  --border:    #e2eae7;
  --border-2:  #d3ded9;

  /* Effects */
  --radius:    16px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 2px rgba(20,33,31,.06), 0 1px 3px rgba(20,33,31,.08);
  --shadow-md: 0 6px 18px rgba(20,33,31,.08), 0 2px 6px rgba(20,33,31,.06);
  --shadow-lg: 0 18px 40px rgba(20,33,31,.14);
  --ring:      0 0 0 3px rgba(36,89,83,.20);

  --maxw: 1160px;
  --nav-h: 66px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

/* ---------- Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 { line-height: 1.2; margin: 0 0 .5em; font-weight: 700; letter-spacing: -.01em; }
h1 { font-size: clamp(2rem, 4.5vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); }
h3 { font-size: 1.25rem; }
p  { margin: 0 0 1rem; }
a  { color: var(--brand-600); text-decoration: none; transition: color .18s ease; }
a:hover { color: var(--brand-800); }
img { max-width: 100%; display: block; }
ul { margin: 0 0 1rem; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.section { padding: 72px 0; }
.section-tight { padding: 48px 0; }
.center { text-align: center; }
.eyebrow {
  display: inline-block;
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--brand-500);
  background: var(--brand-050);
  border: 1px solid var(--brand-100);
  padding: 6px 12px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.lead { font-size: 1.15rem; color: var(--muted); max-width: 62ch; }
.center .lead { margin-left: auto; margin-right: auto; }

/* ---------- Navigation ---------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(20, 52, 48, .92);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid rgba(255,255,255,.08);
  box-shadow: 0 2px 12px rgba(16,48,43,.25);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  color: #fff;
  font-weight: 800;
  font-size: 1.18rem;
  letter-spacing: -.02em;
}
.brand:hover { color: #fff; }
.brand svg { width: 30px; height: 30px; flex: none; }
.brand-accent { color: var(--accent); }

.nav-links {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 4px;
  margin: 0;
  padding: 0;
}
.nav-links a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: rgba(255,255,255,.82);
  font-weight: 500;
  font-size: .96rem;
  padding: 9px 15px;
  border-radius: 10px;
  transition: background .18s ease, color .18s ease;
}
.nav-links a:hover { color: #fff; background: rgba(255,255,255,.10); }
.nav-links a.active { color: #fff; background: rgba(255,255,255,.16); }
.nav-links a.cta {
  background: var(--accent);
  color: var(--brand-900);
  font-weight: 700;
}
.nav-links a.cta:hover { background: #ffb877; color: var(--brand-900); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform .25s ease, opacity .2s ease;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  padding: 13px 24px;
  border-radius: 12px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .12s ease, box-shadow .2s ease, background .2s ease, color .2s ease;
  text-decoration: none;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: var(--brand-600);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { background: var(--brand-700); color: #fff; box-shadow: var(--shadow-md); }
.btn-accent {
  background: var(--accent);
  color: var(--brand-900);
  box-shadow: var(--shadow-sm);
}
.btn-accent:hover { background: #ffb877; color: var(--brand-900); box-shadow: var(--shadow-md); }
.btn-ghost {
  background: transparent;
  color: var(--brand-700);
  border-color: var(--border-2);
}
.btn-ghost:hover { background: var(--surface); border-color: var(--brand-300); color: var(--brand-800); }
.btn-lg { padding: 15px 30px; font-size: 1.06rem; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  color: #eafaf6;
  background:
    radial-gradient(1100px 500px at 78% -10%, rgba(63,139,130,.55), transparent 60%),
    radial-gradient(800px 420px at 8% 120%, rgba(244,162,97,.18), transparent 55%),
    linear-gradient(160deg, var(--brand-800), var(--brand-900));
  overflow: hidden;
}
.hero::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    repeating-radial-gradient(circle at 50% 50%, rgba(255,255,255,.035) 0 1px, transparent 1px 22px);
  opacity: .5;
  pointer-events: none;
}
.hero-inner {
  position: relative;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(56px, 9vw, 104px) 24px;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  gap: 48px;
  align-items: center;
}
.hero .eyebrow { color: #ffd9b0; background: rgba(244,162,97,.14); border-color: rgba(244,162,97,.3); }
.hero h1 { color: #fff; margin-bottom: .35em; }
.hero h1 .grad {
  background: linear-gradient(100deg, #ffd9b0, #7fd6c6);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p.lead { color: rgba(234,250,246,.82); }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.hero-stats {
  display: flex; gap: 34px; margin-top: 40px; flex-wrap: wrap;
}
.hero-stats .stat b {
  display: block; font-size: 1.9rem; font-weight: 800; color: #fff; line-height: 1;
}
.hero-stats .stat span { font-size: .85rem; color: rgba(234,250,246,.7); }

/* Hero disk illustration */
.hero-art {
  display: grid;
  place-items: center;
}
.hero-art svg { width: min(360px, 78vw); height: auto; filter: drop-shadow(0 24px 44px rgba(0,0,0,.4)); }
.spin-slow { transform-origin: 200px 200px; animation: spin 26s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- Cards & grids ---------- */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}
.grid { display: grid; gap: 22px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.feature-card {
  padding: 26px;
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--brand-100); }
.feature-icon {
  width: 48px; height: 48px;
  display: grid; place-items: center;
  border-radius: 12px;
  background: var(--brand-050);
  color: var(--brand-600);
  font-size: 1.35rem;
  margin-bottom: 16px;
}
.feature-card h3 { margin-bottom: .3em; }
.feature-card p { color: var(--muted); margin: 0; font-size: .97rem; }

/* Concept split (image + text) */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 44px;
  align-items: center;
}
.split img { border-radius: var(--radius); box-shadow: var(--shadow-md); }
.term-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.term-list li {
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 4px solid var(--brand-400);
  border-radius: 12px;
}
.term-list b { color: var(--brand-700); }

/* Algorithm cards */
.algo-grid { grid-template-columns: repeat(3, 1fr); }
.algo-card {
  padding: 24px;
  position: relative;
  overflow: hidden;
  transition: transform .2s ease, box-shadow .2s ease;
}
.algo-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.algo-tag {
  display: inline-block;
  font-size: .72rem; font-weight: 700; letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--brand-600);
  background: var(--brand-050);
  padding: 4px 10px; border-radius: 999px;
  margin-bottom: 12px;
}
.algo-card h3 { margin-bottom: .35em; }
.algo-card p { color: var(--muted); font-size: .95rem; margin: 0; }

/* ---------- Callout band ---------- */
.band {
  background: linear-gradient(140deg, var(--brand-700), var(--brand-900));
  color: #eafaf6;
  border-radius: 24px;
  padding: clamp(36px, 5vw, 60px);
  text-align: center;
}
.band h2 { color: #fff; }
.band p { color: rgba(234,250,246,.82); max-width: 60ch; margin-left: auto; margin-right: auto; }

/* =============================================================
   GUIDE PAGE
   ============================================================= */
.doc { display: grid; grid-template-columns: 240px 1fr; gap: 44px; align-items: start; }
.doc-nav { position: sticky; top: calc(var(--nav-h) + 20px); }
.doc-nav h4 {
  font-size: .78rem; text-transform: uppercase; letter-spacing: .1em;
  color: var(--faint); margin-bottom: 12px;
}
.doc-nav ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 2px; }
.doc-nav a {
  display: block; padding: 8px 12px; border-radius: 8px;
  color: var(--muted); font-size: .93rem; border-left: 2px solid transparent;
}
.doc-nav a:hover { background: var(--surface); color: var(--brand-700); }

.doc-body > section { scroll-margin-top: calc(var(--nav-h) + 20px); margin-bottom: 46px; }
.doc-body h2 { display: flex; align-items: center; gap: 12px; }
.doc-body h2 .num {
  flex: none;
  width: 34px; height: 34px; border-radius: 10px;
  display: grid; place-items: center;
  background: var(--brand-600); color: #fff; font-size: .95rem; font-weight: 700;
}
.doc-body p, .doc-body li { color: var(--muted); }
.doc-body strong { color: var(--text); }

.steps { list-style: none; counter-reset: step; padding: 0; margin: 0; display: grid; gap: 16px; }
.steps li {
  counter-increment: step;
  position: relative;
  padding: 18px 20px 18px 62px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
}
.steps li::before {
  content: counter(step);
  position: absolute; left: 16px; top: 16px;
  width: 32px; height: 32px; border-radius: 9px;
  background: var(--brand-050); color: var(--brand-600);
  display: grid; place-items: center; font-weight: 700;
}
.steps li b { color: var(--text); }

.callout {
  display: flex; gap: 14px;
  padding: 16px 18px;
  border-radius: 12px;
  background: var(--brand-050);
  border: 1px solid var(--brand-100);
  margin: 18px 0;
}
.callout .ico { font-size: 1.2rem; color: var(--brand-600); flex: none; }
.callout p { margin: 0; color: var(--brand-800); }
.callout.warn { background: #fff6ed; border-color: #ffd9b0; }
.callout.warn .ico, .callout.warn p { color: var(--accent-dk); }

kbd {
  font-family: ui-monospace, 'SFMono-Regular', Menlo, Consolas, monospace;
  font-size: .82rem;
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-bottom-width: 2px;
  border-radius: 7px;
  padding: 3px 9px;
  color: var(--text);
  box-shadow: var(--shadow-sm);
}

.table-wrap { overflow-x: auto; border-radius: 14px; border: 1px solid var(--border); }
table.doc-table { width: 100%; border-collapse: collapse; background: var(--surface); }
table.doc-table th, table.doc-table td { text-align: left; padding: 13px 16px; font-size: .94rem; }
table.doc-table thead th { background: var(--brand-050); color: var(--brand-800); font-weight: 700; }
table.doc-table tbody tr { border-top: 1px solid var(--border); }
table.doc-table tbody td { color: var(--muted); }
table.doc-table tbody td b { color: var(--text); }

.legend-row { display: flex; flex-wrap: wrap; gap: 20px; margin: 8px 0 4px; }
.legend-row .lg { display: inline-flex; align-items: center; gap: 8px; font-size: .92rem; color: var(--muted); }
.legend-row .dot { width: 14px; height: 14px; border-radius: 50%; flex: none; box-shadow: var(--shadow-sm); }

/* =============================================================
   SIMULATE PAGE
   ============================================================= */
.sim-head { padding: 40px 0 8px; }
.sim-head h1 { margin-bottom: .2em; }
.sim-head p { color: var(--muted); margin: 0; }

.sim-grid {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 24px;
  align-items: start;
  margin-top: 26px;
}
.panel { padding: 24px; }
.panel-title {
  font-size: .8rem; text-transform: uppercase; letter-spacing: .1em;
  color: var(--faint); font-weight: 700; margin: 0 0 18px;
  display: flex; align-items: center; gap: 8px;
}
.panel-title::before {
  content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--brand-400);
}

.field { margin-bottom: 18px; }
.field label {
  display: block;
  font-size: .86rem; font-weight: 600; color: var(--text);
  margin-bottom: 7px;
}
.field .hint { font-weight: 400; color: var(--faint); font-size: .8rem; }
.form-control {
  display: block; width: 100%;
  font-family: inherit; font-size: .97rem;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border-2);
  border-radius: 10px;
  padding: 11px 13px;
  transition: border-color .18s ease, box-shadow .18s ease, background .18s ease;
}
.form-control:focus {
  outline: none;
  border-color: var(--brand-400);
  background: #fff;
  box-shadow: var(--ring);
}
select.form-control {
  appearance: none; -webkit-appearance: none;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%235c6c69' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'><polyline points='6 9 12 15 18 9'/></svg>");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 38px;
}
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }

.sim-actions { display: flex; gap: 12px; margin-top: 22px; }
.sim-actions .btn { flex: 1; }

/* Visualization panel */
.viz-panel { padding: 20px; }
.viz-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 6px; flex-wrap: wrap; }
.viz-badge {
  font-size: .82rem; font-weight: 600;
  color: var(--brand-700); background: var(--brand-050);
  border: 1px solid var(--brand-100);
  padding: 6px 12px; border-radius: 999px;
}

#disk-wrap {
  width: 100%;
  max-width: 460px;
  margin: 6px auto 0;
  padding: 14px;
  background: radial-gradient(120% 120% at 50% 0%, #1d2422, #0e1211);
  border-radius: var(--radius);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.04), var(--shadow-md);
}
#disk-svg { width: 100%; height: auto; display: block; }

#head-arm {
  transition: transform 0.45s cubic-bezier(0.4, 0.0, 0.2, 1);
  transform-origin: 380px 200px;
  transform-box: view-box;
}
#disk-tracks circle { fill: none; stroke: #6f8b85; stroke-width: 0.6; opacity: .35; }
#disk-tracks circle.track-active { stroke: var(--coral); stroke-width: 1.6; opacity: 1; }

.marker-dot { fill: #a8dadc; stroke: var(--brand-600); stroke-width: 1; transition: all .3s ease; }
.marker-dot.served { fill: var(--success); r: 5; }
.marker-dot.current { fill: var(--coral); r: 7; }

/* Playback controls */
#playback-controls {
  display: flex; align-items: center; justify-content: center;
  flex-wrap: wrap; gap: 8px;
  margin: 18px auto 4px;
  padding: 14px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 14px;
  max-width: 620px;
}
.pb-btn {
  min-width: 44px; height: 42px;
  font-size: 15px;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--surface);
  color: var(--brand-700);
  border: 1px solid var(--border-2);
  border-radius: 10px;
  cursor: pointer;
  transition: all .16s ease;
}
.pb-btn:hover { border-color: var(--brand-300); color: var(--brand-800); box-shadow: var(--shadow-sm); }
#btn-play {
  min-width: 56px;
  background: var(--brand-600); color: #fff; border-color: var(--brand-600);
}
#btn-play:hover { background: var(--brand-700); border-color: var(--brand-700); color: #fff; }
.speed-wrap { display: flex; align-items: center; gap: 8px; margin-left: 10px; }
.speed-wrap label { margin: 0; font-size: .86rem; font-weight: 600; color: var(--muted); }
#speed-slider { width: 118px; accent-color: var(--brand-600); }
#speed-label { min-width: 58px; font-family: ui-monospace, monospace; font-size: .85rem; color: var(--brand-700); }
#step-indicator {
  margin-left: 8px;
  font-family: ui-monospace, monospace;
  font-size: .85rem; font-weight: 600; color: var(--brand-800);
  min-width: 150px; text-align: center;
  background: var(--brand-050);
  border: 1px solid var(--brand-100);
  border-radius: 8px; padding: 8px 10px;
}

/* Result cards */
.results { display: grid; gap: 24px; margin-top: 26px; }
.result-card { padding: 26px; }
.result-card > h2 { text-align: center; margin-bottom: 6px; }
#plt_alg_name, #cmpr-head {
  text-align: center; font-size: 1.5rem; font-weight: 700; color: var(--brand-700);
}
#plt_alg_name:empty, #cmpr-head:empty { display: none; }
#graph_area, #cmpr_area {
  visibility: hidden;
  margin: 14px auto 0;
  width: 100%;
  border-radius: 12px;
  overflow: hidden;
}
#cal-seek, #leastValue {
  text-align: center;
  font-size: 1.15rem; font-weight: 600;
  color: var(--brand-800);
  margin: 14px auto 0;
  max-width: 70ch;
}
#cal-seek:empty, #leastValue:empty { display: none; }
#plt_alg_seek { text-align: center; color: var(--muted); }
.result-hint { text-align: center; color: var(--faint); font-size: .95rem; }

/* Legacy status placeholders (kept for JS compatibility, visually hidden) */
#am_alg_name, #cl-seek, #am_alg_seek { display: none; }

/* =============================================================
   ABOUT PAGE
   ============================================================= */
.team-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; max-width: 720px; margin: 0 auto; }
.member {
  display: flex; align-items: center; gap: 16px;
  padding: 20px 22px;
  transition: transform .2s ease, box-shadow .2s ease;
}
.member:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.avatar {
  width: 54px; height: 54px; flex: none;
  border-radius: 14px;
  display: grid; place-items: center;
  font-weight: 700; font-size: 1.15rem; color: #fff;
  background: linear-gradient(140deg, var(--brand-500), var(--brand-800));
}
.member .name { font-weight: 700; color: var(--text); }
.member .roll { font-size: .88rem; color: var(--faint); }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--brand-900);
  color: rgba(234,250,246,.72);
  padding: 40px 0 28px;
  margin-top: 40px;
}
.footer-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap;
}
.footer-brand { display: flex; align-items: center; gap: 10px; color: #fff; font-weight: 700; }
.footer-brand svg { width: 26px; height: 26px; }
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer-links a { color: rgba(234,250,246,.72); font-size: .93rem; }
.footer-links a:hover { color: #fff; }
.site-footer .fine { width: 100%; text-align: center; font-size: .84rem; color: rgba(234,250,246,.5); margin-top: 22px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.08); }

/* ---------- Animations ---------- */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 940px) {
  .hero-inner { grid-template-columns: 1fr; text-align: center; }
  .hero .eyebrow { margin-inline: auto; }
  .hero-cta, .hero-stats { justify-content: center; }
  .hero-art { order: -1; }
  .grid-3, .algo-grid { grid-template-columns: repeat(2, 1fr); }
  .doc { grid-template-columns: 1fr; }
  .doc-nav { display: none; }
  .sim-grid { grid-template-columns: 1fr; }
}
@media (max-width: 760px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: absolute; top: var(--nav-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 4px;
    background: var(--brand-800);
    padding: 12px 16px 18px;
    border-bottom: 1px solid rgba(255,255,255,.08);
    box-shadow: var(--shadow-lg);
    transform: translateY(-8px);
    opacity: 0; visibility: hidden;
    transition: opacity .2s ease, transform .2s ease, visibility .2s;
  }
  .nav-links.open { opacity: 1; visibility: visible; transform: none; }
  .split { grid-template-columns: 1fr; }
  .grid-3, .grid-2, .algo-grid, .team-grid { grid-template-columns: 1fr; }
  .section { padding: 52px 0; }
  .sim-actions { flex-direction: column; }
  .hero-stats { gap: 22px; }
}