/* VT Exam Prep — Von Taylor Labs design language (shared with PacketCrew):
   deep navy + cyan glow, monospace-first, bracket buttons. */
:root {
  --bg: #0b1220;
  --bg-panel: #111c33;
  --bg-input: #0b1428;
  --line: #22345a;
  --line-bright: #2c426e;
  --text: #e6edf7;
  --text-dim: #8fa3bf;
  --glow: #22d3ee;
  --glow-teal: #2dd4bf;
  --action: #2563eb;
  --action-hover: #1d4ed8;
  --warn: #f59e0b;
  --bad: #f87171;
  --good: #34d399;
  --mono: ui-monospace, "Cascadia Code", "JetBrains Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--mono);
  line-height: 1.55;
}
a { color: var(--glow); }
img { max-width: 100%; display: block; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 20px; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(11, 18, 32, .92); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; gap: 22px; padding-top: 12px; padding-bottom: 12px; }
.brand { font-weight: 700; font-size: 20px; letter-spacing: .04em; color: var(--text); text-decoration: none; white-space: nowrap; }
.brand .vt { color: var(--glow); text-shadow: 0 0 14px rgba(34, 211, 238, .55); }
.brand small { display: block; font-size: 10px; letter-spacing: .22em; color: var(--text-dim); font-weight: 400; }
.main-nav { display: flex; gap: 18px; margin-left: auto; align-items: center; flex-wrap: wrap; }
.main-nav a { color: var(--text-dim); text-decoration: none; font-size: 13px; letter-spacing: .1em; text-transform: uppercase; }
.main-nav a:hover { color: var(--glow); }
.user-box { display: flex; gap: 10px; align-items: center; font-size: 13px; color: var(--text-dim); }
.sub-badge { color: #06281f; background: var(--glow-teal); border-radius: 999px; padding: 1px 9px; font-size: 11px; font-weight: 700; letter-spacing: .06em; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block; font-family: var(--mono); font-size: 14px; letter-spacing: .08em;
  text-transform: uppercase; text-decoration: none; cursor: pointer;
  color: var(--glow); background: transparent; border: 1px solid var(--line-bright);
  padding: 11px 18px; border-radius: 6px; transition: all .16s ease;
}
.btn:hover { border-color: var(--glow); box-shadow: 0 0 16px rgba(34, 211, 238, .25); color: #a5f3fc; }
.btn.primary { background: var(--action); border-color: var(--action); color: #fff; }
.btn.primary:hover { background: var(--action-hover); box-shadow: 0 0 18px rgba(37, 99, 235, .45); }
.btn.small { padding: 7px 12px; font-size: 12px; }
.btn[disabled] { opacity: .45; cursor: not-allowed; box-shadow: none; }

/* ---------- hero & sections ---------- */
.hero { padding: 64px 0 30px; }
.hero-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 36px; align-items: center; }
.badge {
  display: inline-block; border: 1px solid var(--line-bright); color: var(--glow);
  border-radius: 999px; padding: 4px 14px; font-size: 12px; letter-spacing: .18em; margin-bottom: 18px;
}
h1.glow {
  font-size: clamp(34px, 5.4vw, 58px); line-height: 1.08; margin: 0 0 18px;
  text-shadow: 0 0 24px rgba(34, 211, 238, .45);
}
h1.glow .alt { color: var(--glow); }
.lede { color: var(--text-dim); font-size: 17px; max-width: 56ch; }
.lede strong { color: var(--text); }
.hero-ctas { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 26px; }
.hero-art { border: 1px solid var(--line); border-radius: 14px; overflow: hidden; box-shadow: 0 0 44px rgba(34, 211, 238, .12); }
section { padding: 44px 0; }
h2.section-title { font-size: 26px; margin: 0 0 8px; }
h2.section-title .n { color: var(--glow); }
.section-sub { color: var(--text-dim); margin: 0 0 26px; max-width: 70ch; }

/* ---------- flow steps ---------- */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.step { background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; padding: 22px; }
.step .num { color: var(--glow); font-size: 13px; letter-spacing: .2em; }
.step h3 { margin: 8px 0 8px; font-size: 18px; }
.step p { color: var(--text-dim); font-size: 14px; margin: 0 0 12px; }

/* ---------- domain cards ---------- */
.domain-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.domain-card { background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; padding: 20px; display: flex; flex-direction: column; gap: 8px; }
.domain-card:hover { border-color: var(--line-bright); }
.domain-card .meta { display: flex; justify-content: space-between; color: var(--text-dim); font-size: 12px; letter-spacing: .12em; text-transform: uppercase; }
.domain-card h3 { margin: 2px 0 0; font-size: 17px; }
.domain-card p { color: var(--text-dim); font-size: 13.5px; margin: 0; flex: 1; }
.domain-card .links { display: flex; gap: 14px; font-size: 13px; margin-top: 8px; flex-wrap: wrap; }
.domain-card .links a { text-decoration: none; }
.domain-card .links a:hover { text-decoration: underline; }

/* ---------- episode banner ---------- */
.episode-banner {
  display: flex; gap: 20px; align-items: center; flex-wrap: wrap;
  background: linear-gradient(90deg, rgba(34, 211, 238, .10), rgba(45, 212, 191, .05));
  border: 1px solid var(--line-bright); border-radius: 12px; padding: 20px 24px;
}
.episode-banner .txt { flex: 1; min-width: 260px; }
.episode-banner h3 { margin: 0 0 4px; }
.episode-banner p { margin: 0; color: var(--text-dim); font-size: 14px; }

/* ---------- compare / pricing ---------- */
.compare { width: 100%; border-collapse: collapse; background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; overflow: hidden; }
.compare th, .compare td { padding: 13px 16px; border-bottom: 1px solid var(--line); text-align: left; font-size: 14.5px; }
.compare th { background: var(--bg-input); letter-spacing: .06em; }
.compare tr:last-child td { border-bottom: none; }
.compare .yes { color: var(--good); }
.compare .no { color: var(--text-dim); }
.price-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.price-card { background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; padding: 26px; }
.price-card.featured { border-color: var(--glow); box-shadow: 0 0 30px rgba(34, 211, 238, .12); }
.price-card .amount { font-size: 40px; margin: 6px 0; }
.price-card .amount span { font-size: 15px; color: var(--text-dim); }
.price-card ul { color: var(--text-dim); font-size: 14px; padding-left: 18px; }
.price-card ul li { margin: 6px 0; }
.note { color: var(--text-dim); font-size: 13px; }

/* ---------- teacher band ---------- */
.teacher { display: grid; grid-template-columns: .8fr 1.2fr; gap: 30px; align-items: center; }
.teacher img { border: 1px solid var(--line); border-radius: 14px; }

/* ---------- practice app ---------- */
.tabs { display: flex; gap: 10px; flex-wrap: wrap; margin: 22px 0 6px; }
.tab {
  font-family: var(--mono); font-size: 13px; cursor: pointer; color: var(--text-dim);
  background: var(--bg-panel); border: 1px solid var(--line); border-radius: 999px; padding: 8px 15px;
}
.tab:hover { color: var(--text); border-color: var(--line-bright); }
.tab.active { color: #062a38; background: var(--glow); border-color: var(--glow); font-weight: 700; }
.domain-head { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin: 14px 0 4px; }
.domain-head h2 { margin: 0; font-size: 24px; }
.ep-chips { display: flex; gap: 8px; flex-wrap: wrap; margin: 8px 0 18px; }
.ep-chip { font-size: 12px; border: 1px solid var(--line); border-radius: 999px; padding: 4px 11px; color: var(--text-dim); text-decoration: none; }
a.ep-chip { color: var(--glow); border-color: var(--line-bright); }
a.ep-chip:hover { border-color: var(--glow); }

.qcard { background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; padding: 22px; margin: 0 0 18px; }
.qcard .qmeta { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 12px; }
.chip { font-size: 11px; letter-spacing: .1em; text-transform: uppercase; border: 1px solid var(--line-bright); color: var(--glow); border-radius: 999px; padding: 2px 10px; }
.chip.diff { color: var(--text-dim); border-color: var(--line); }
.chip.diff.hard { color: var(--warn); }
.stem { font-size: 16.5px; white-space: pre-wrap; margin: 0 0 16px; }
.options { display: grid; gap: 10px; }
.option {
  display: flex; gap: 12px; align-items: flex-start; text-align: left; width: 100%;
  font-family: var(--mono); font-size: 15px; color: var(--text); cursor: pointer;
  background: var(--bg-input); border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px;
}
.option:hover { border-color: var(--line-bright); }
.option.selected { border-color: var(--glow); box-shadow: 0 0 12px rgba(34, 211, 238, .18); }
.option.correct { border-color: var(--good); background: rgba(52, 211, 153, .08); }
.option.wrong { border-color: var(--bad); background: rgba(248, 113, 113, .08); }
.option .letter { color: var(--glow); font-weight: 700; }
.qactions { display: flex; gap: 10px; margin-top: 16px; flex-wrap: wrap; align-items: center; }
.result { margin-top: 16px; }
.verdict { font-weight: 700; letter-spacing: .04em; }
.verdict.right { color: var(--good); }
.verdict.wrongv { color: var(--bad); }
.explanation { border-left: 3px solid var(--glow-teal); background: var(--bg-input); padding: 14px 16px; border-radius: 0 8px 8px 0; margin-top: 12px; font-size: 14.5px; color: var(--text); }
.explanation .h { color: var(--glow-teal); font-size: 12px; letter-spacing: .16em; text-transform: uppercase; display: block; margin-bottom: 6px; }
.locked {
  border: 1px dashed var(--line-bright); border-radius: 10px; padding: 18px;
  background: repeating-linear-gradient(45deg, rgba(34, 211, 238, .03) 0 12px, transparent 12px 24px);
  text-align: center;
}
.locked .lock { font-size: 22px; }
.locked h4 { margin: 6px 0; }
.locked p { color: var(--text-dim); font-size: 14px; margin: 0 auto 14px; max-width: 52ch; }

/* ---------- session setup & run ---------- */
.setup-block { background: var(--bg-panel); border: 1px solid var(--line); border-radius: 12px; padding: 20px 22px; margin: 0 0 18px; }
.setup-block h3 { margin: 0 0 14px; font-size: 17px; }
.setup-block h3 .n { color: var(--glow); }
.setup-domain { background: var(--bg-input); border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; margin: 0 0 12px; }
.setup-domain.off { opacity: .45; }
.setup-domain-head { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; cursor: pointer; font-size: 15.5px; font-weight: 700; }
.setup-domain input[type="checkbox"], .topic-item input[type="checkbox"] { accent-color: var(--glow); width: 16px; height: 16px; cursor: pointer; flex: none; }
.setup-domain .ep-chips { margin: 10px 0 2px; }
.topic-list { display: flex; flex-wrap: wrap; gap: 6px 16px; margin-top: 10px; }
.topic-item { display: inline-flex; gap: 6px; align-items: center; font-size: 13px; color: var(--text-dim); cursor: pointer; }
.topic-item .tcount { color: var(--glow); font-size: 11.5px; }
.setup-actions { display: flex; gap: 14px; align-items: center; flex-wrap: wrap; }
.session-head { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin: 18px 0 10px; }
.session-head h2 { margin: 0; font-size: 24px; }
.session-head .btn { margin-left: auto; }
.progress { height: 8px; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; margin: 0 0 20px; background: var(--bg-input); }
.progress-bar { height: 100%; width: 0; background: linear-gradient(90deg, var(--glow), var(--glow-teal)); transition: width .3s ease; }
.summary-card { border: 1px solid var(--glow-teal); border-radius: 12px; padding: 22px; margin: 4px 0 18px; text-align: center; background: linear-gradient(90deg, rgba(45, 212, 191, .10), rgba(34, 211, 238, .05)); }
.summary-card h3 { margin: 0 0 6px; }
.summary-card p { color: var(--text-dim); margin: 4px 0 12px; }
.summary-card p strong { color: var(--text); }

/* ---------- auth panel / forms ---------- */
.auth-panel { background: var(--bg-panel); border: 1px solid var(--line-bright); border-radius: 12px; padding: 20px; margin: 18px 0; }
.auth-panel h3 { margin-top: 0; }
.inline-form { display: flex; gap: 10px; flex-wrap: wrap; }
.inline-form input {
  flex: 1; min-width: 240px; font-family: var(--mono); font-size: 15px; color: var(--text);
  background: var(--bg-input); border: 1px solid var(--line); border-radius: 6px; padding: 11px 14px;
}
.inline-form input:focus { outline: none; border-color: var(--glow); }
.form-msg { font-size: 13.5px; color: var(--text-dim); margin-top: 10px; }
.form-msg.err { color: var(--bad); }
.form-msg.ok { color: var(--good); }

/* ---------- legal docs ---------- */
.doc { max-width: 780px; margin: 0 auto; padding: 40px 20px 60px; }
.doc h1 { font-size: 30px; }
.doc h2 { font-size: 19px; margin-top: 30px; color: var(--glow); }
.doc p, .doc li { color: var(--text-dim); font-size: 15px; }
.doc .updated { font-size: 13px; letter-spacing: .08em; text-transform: uppercase; }
.eyebrow { color: var(--glow); font-size: 12px; letter-spacing: .22em; text-transform: uppercase; }

/* ---------- footer ---------- */
footer { border-top: 1px solid var(--line); margin-top: 30px; }
footer .wrap { display: flex; gap: 14px; align-items: center; justify-content: space-between; flex-wrap: wrap; padding-top: 20px; padding-bottom: 26px; }
.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer-links a { color: var(--text-dim); text-decoration: none; font-size: 12.5px; letter-spacing: .08em; text-transform: uppercase; }
.footer-links a:hover { color: var(--glow); }
footer .fine { color: var(--text-dim); font-size: 12.5px; }

@media (max-width: 860px) {
  .hero-grid, .teacher { grid-template-columns: 1fr; }
  .steps, .domain-grid, .price-grid { grid-template-columns: 1fr; }
  .site-header .wrap { flex-wrap: wrap; }
  .main-nav { margin-left: 0; }
}