:root {
  --bg: #08090B;
  --bg-elevated: #0D0F12;
  --card: rgba(255,255,255,0.06);
  --card-border: rgba(255,255,255,0.10);
  --text: #EEF1F5;
  --text-dim: #8B93A1;
  --text-sub: #5C6470;
  --orange: #FF7A1A;
  --blue: #2FA8FF;
  --green: #27C36F;
  --purple: #9B5DE5;
  --grey: #7F8C9A;
  --danger: #FF5A5A;
  --success: #27C36F;
  --radius: 1.1rem;
  --shadow: 0 12px 40px rgba(0,0,0,0.45);
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, Arial, sans-serif;
  line-height: 1.5;
}

body {
  background:
    radial-gradient(circle at 12% -5%, rgba(255,122,26,0.12), transparent 42%),
    radial-gradient(circle at 88% 15%, rgba(47,168,255,0.15), transparent 48%),
    var(--bg);
  padding-bottom: 40px;
}

.topnav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  background: rgba(8,9,11,0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--card-border);
}

.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); }
.brand-name { font-weight: 700; font-size: 16px; }

.topnav-links { display: flex; gap: 14px; align-items: center; }
.topnav-links a, .topnav-links button {
  color: var(--text-dim);
  text-decoration: none;
  background: none;
  border: none;
  font-size: 14px;
  cursor: pointer;
  padding: 4px 0;
}
.topnav-links a:hover, .topnav-links button:hover { color: var(--text); }

main { padding: 24px 16px; max-width: 800px; margin: 0 auto; }

.card {
  background: linear-gradient(155deg, var(--card), rgba(255,255,255,0.04) 60%);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px 24px;
  margin-bottom: 20px;
}

h1 { font-size: 26px; margin: 0 0 10px; line-height: 1.2; }
h2 { font-size: 20px; margin: 0 0 14px; }
p { margin: 0 0 16px; color: var(--text-dim); }
.eyebrow { font-size: 12px; color: var(--orange); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 8px; }

.disclaimer {
  background: rgba(47,168,255,0.08);
  border-left: 3px solid var(--blue);
  padding: 14px 16px;
  border-radius: 8px;
  color: var(--text-dim);
  font-size: 13px;
  margin: 20px 0;
}
.disclaimer strong { color: var(--text); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 22px;
  border: none;
  border-radius: 9999px;
  font-size: 15px;
  font-weight: 650;
  cursor: pointer;
  text-decoration: none;
  transition: transform .08s, opacity .15s;
}
.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn-primary { background: linear-gradient(90deg, var(--orange), var(--blue)); color: #000; }
.btn-ghost { background: rgba(255,255,255,0.08); color: var(--text); border: 1px solid var(--card-border); }
.btn-danger { background: rgba(255,90,90,0.15); color: #FF9B9A; border: 1px solid rgba(255,90,90,0.3); }

.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 20px; }

form label { display: block; font-size: 12px; color: var(--text-dim); margin: 14px 0 6px; }
form input {
  width: 100%;
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--card-border);
  border-radius: 10px;
  padding: 13px 14px;
  color: var(--text);
  font-size: 15px;
}
form input:focus { outline: none; border-color: var(--blue); }
.err { color: #FF9B9A; font-size: 13px; margin: -8px 0 14px; }

.timer-bar {
  height: 4px;
  background: var(--card-border);
  border-radius: 2px;
  overflow: hidden;
  margin-bottom: 18px;
}
.timer-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--orange), var(--blue));
  width: 100%;
  transition: width 1s linear;
}
.timer-text { font-size: 13px; color: var(--text-dim); margin-bottom: 8px; }

.question-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 18px;
  font-size: 13px;
  color: var(--text-dim);
}

.category-pill {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(255,255,255,0.08);
  font-size: 12px;
  color: var(--text-dim);
  margin-bottom: 14px;
}

.prompt {
  font-size: 17px;
  margin-bottom: 20px;
  color: var(--text);
}

.options { display: flex; flex-direction: column; gap: 10px; }
.option {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  cursor: pointer;
  transition: background .15s, border-color .15s;
}
.option:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,122,26,0.4); }
.option.selected { background: rgba(47,168,255,0.12); border-color: var(--blue); }
.option.correct { background: rgba(39,195,111,0.12); border-color: var(--success); }
.option.incorrect { background: rgba(255,90,90,0.12); border-color: var(--danger); }
.option-id {
  width: 28px; height: 28px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: rgba(255,255,255,0.1);
  font-size: 13px; font-weight: 700;
}
.option.selected .option-id { background: var(--blue); color: #000; }
.option.correct .option-id { background: var(--success); color: #000; }
.option.incorrect .option-id { background: var(--danger); color: #000; }

.pattern-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  max-width: 320px;
  margin: 0 auto 24px;
}
.pattern-cell {
  aspect-ratio: 1;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--card-border);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px;
}
.pattern-cell.missing { border-style: dashed; border-color: var(--orange); background: rgba(255,122,26,0.06); }

.number-sequence { font-size: 22px; letter-spacing: 0.08em; text-align: center; margin: 20px 0; }
.number-sequence .q { color: var(--orange); }

.verbal-prompt { font-size: 18px; text-align: center; margin: 20px 0; }
.verbal-prompt .rel { color: var(--blue); font-weight: 600; }

.spatial-prompt { text-align: center; margin: 20px 0; }
.spatial-prompt svg { max-width: 220px; height: auto; }

.logic-prompt { font-size: 16px; margin: 20px 0; }
.logic-prompt ul { padding-left: 20px; margin: 10px 0; }
.logic-prompt li { margin-bottom: 6px; color: var(--text-dim); }
.logic-conclusion { font-weight: 600; color: var(--text); margin-top: 14px; }

.cube-view { display: inline-block; margin: 6px; }
.cube-view svg { width: 80px; height: 80px; }

.results-summary { text-align: center; margin-bottom: 30px; }
.big-score { font-size: 56px; font-weight: 800; background: linear-gradient(90deg, var(--orange), var(--blue)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.result-label { font-size: 13px; color: var(--text-dim); margin-top: 8px; }

.category-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid var(--card-border);
}
.category-name { font-weight: 600; }
.category-score { color: var(--text-dim); }

.review-card { margin-bottom: 14px; }
.review-card .q-text { font-size: 14px; color: var(--text-dim); margin-bottom: 8px; }
.review-answer { font-size: 14px; }
.correct-text { color: var(--success); }
.wrong-text { color: var(--danger); }

.empty-state { text-align: center; padding: 40px 20px; color: var(--text-dim); }

.footer-disclaimer {
  text-align: center;
  font-size: 12px;
  color: var(--text-sub);
  margin-top: 30px;
}

@media (max-width: 600px) {
  h1 { font-size: 22px; }
  .btn { width: 100%; }
  .btn-row .btn { flex: 1; }
  .pattern-grid { max-width: 260px; }
}

.mode-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-top: 24px;
}

.mode-card {
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 22px 18px;
  text-align: center;
}

.mode-card h3 { margin: 0 0 8px; font-size: 18px; }

.mode-card p {
  color: var(--text-dim);
  font-size: 14px;
  min-height: 60px;
  margin: 0 0 16px;
}

.subtest-count {
  display: inline-block;
  background: rgba(255,122,26,0.12);
  border: 1px solid rgba(255,122,26,0.35);
  color: var(--orange);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 999px;
  margin: 10px 0 6px;
}

.digit-span-prompt { text-align: center; margin: 20px 0; }

.digit-display {
  text-align: center;
  font-size: 38px;
  letter-spacing: 0.18em;
  font-weight: 700;
  color: var(--text);
  margin: 24px auto;
  min-height: 60px;
}

.digit-input {
  width: 100%;
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 16px 14px;
  color: var(--text);
  font-size: 28px;
  letter-spacing: 0.15em;
  text-align: center;
  font-family: inherit;
}

.digit-input:focus { outline: none; border-color: var(--blue); }

.ps-pair {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin: 24px 0;
  flex-wrap: wrap;
}

.ps-string {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--text);
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--card-border);
  border-radius: 10px;
  padding: 16px 22px;
  min-width: 90px;
  text-align: center;
  word-break: break-all;
}

.ps-vs {
  color: var(--text-dim);
  font-size: 14px;
}

.vocab-prompt { text-align: center; margin: 20px 0; }

.target-word {
  font-size: 32px;
  font-weight: 700;
  color: var(--blue);
  margin: 14px 0;
}

.arithmetic-prompt {
  font-size: 17px;
  line-height: 1.6;
  text-align: center;
  margin: 20px 0;
  color: var(--text);
}

@media (max-width: 600px) {
  .mode-cards { grid-template-columns: 1fr; }
  .ps-string { font-size: 22px; padding: 12px 16px; }
}