:root {
  --bg: #05101d;
  --bg2: #0b1b31;
  --card: rgba(16, 32, 56, 0.7);
  --line: rgba(255, 255, 255, 0.12);
  --text: #ecf3ff;
  --muted: #a8bdd7;
  --accent: #4ed2ff;
  --accent-2: #70f0b0;
  --good: #7cf1ab;
  --bad: #ff8b8b;
  --warn: #ffd36e;
  --shadow: 0 20px 45px rgba(0,0,0,0.35);
  font-synthesis-weight: none;
}
* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; }
body {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top, #16345d 0%, var(--bg) 44%, #04101d 100%);
}
button { font: inherit; cursor: pointer; }
img { max-width: 100%; display: block; }
.app-shell { min-height: 100vh; padding: 20px 16px 40px; }
.topbar, .quiz-head, .overlay-head { display: flex; justify-content: space-between; gap: 16px; align-items: center; }
.topbar { max-width: 1100px; margin: 0 auto 18px; }
h1, h2, h3, p { margin: 0; }
.eyebrow { color: var(--accent); font-size: 0.72rem; letter-spacing: 0.14em; text-transform: uppercase; }
.subtitle { color: var(--muted); margin-top: 4px; }
.screen { display: none; max-width: 1100px; margin: 0 auto; }
.screen.active { display: block; }
.glass {
  background: var(--card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow);
}
.hero-card { display: grid; grid-template-columns: 1.3fr 1fr; gap: 20px; padding: 24px; }
.hero-copy h2 { font-size: clamp(1.8rem, 5vw, 3rem); margin: 8px 0 10px; }
.hero-copy p:last-child { color: var(--muted); line-height: 1.55; }
.hero-tag { display: inline-block; padding: 8px 12px; border-radius: 999px; background: rgba(78,210,255,0.12); color: var(--accent); }
.hero-stats, .results-stats, .progress-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.stat { background: rgba(255,255,255,0.05); border: 1px solid var(--line); padding: 18px 14px; border-radius: 20px; text-align: center; }
.stat span { display: block; font-size: clamp(1.5rem, 5vw, 2.25rem); font-weight: 800; }
.stat label { display: block; margin-top: 8px; color: var(--muted); font-size: 0.95rem; }
.mode-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-top: 18px; }
.mode-card, .primary-btn, .ghost-btn, .danger-btn {
  border-radius: 20px; border: 1px solid var(--line); padding: 18px 16px; transition: transform 140ms ease, border-color 140ms ease, background 140ms ease;
}
.mode-card { text-align: left; background: rgba(255,255,255,0.05); color: var(--text); }
.mode-card:hover, .primary-btn:hover, .ghost-btn:hover, .danger-btn:hover { transform: translateY(-1px); }
.mode-title { display: block; font-weight: 800; font-size: 1.1rem; margin-bottom: 6px; }
.mode-desc { display: block; color: var(--muted); }
.primary-btn { background: linear-gradient(135deg, #4ed2ff, #70f0b0); color: #062134; font-weight: 800; }
.ghost-btn { background: rgba(255,255,255,0.05); color: var(--text); }
.danger-btn { background: rgba(255, 92, 92, 0.1); color: #ffd3d3; }
.release-gate { margin-top: 18px; padding: 22px; }
.release-gate h3 { margin-bottom: 10px; }
.release-gate p, .release-gate li { color: var(--muted); line-height: 1.55; }
.release-gate ul { padding-left: 18px; margin: 12px 0 0; }
.quiz-head, .kit-stage, .results-card, .overlay { padding: 22px; }
.quiz-head { margin-bottom: 14px; }
.head-stats { display: flex; gap: 10px; flex-wrap: wrap; }
.pill { padding: 8px 12px; border-radius: 999px; background: rgba(255,255,255,0.07); border: 1px solid var(--line); }
.kit-stage { display: grid; grid-template-columns: minmax(250px, 420px) 1fr; gap: 20px; align-items: center; }
.kit-wrap { display: grid; place-items: center; min-height: 360px; background: radial-gradient(circle at top, rgba(78,210,255,0.18) 0%, rgba(255,255,255,0.04) 52%, rgba(255,255,255,0.02) 100%); border-radius: 24px; border: 1px solid var(--line); }
.kit-image { width: min(100%, 340px); filter: drop-shadow(0 16px 28px rgba(0,0,0,0.32)); }
.question-text h3 { font-size: clamp(1.5rem, 4vw, 2.2rem); margin: 8px 0 10px; }
.question-text p:last-child { color: var(--muted); line-height: 1.55; }
.answers-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; margin-top: 16px; }
.answer-btn { min-height: 76px; text-align: left; background: rgba(255,255,255,0.05); color: var(--text); border: 1px solid var(--line); border-radius: 20px; padding: 16px; }
.answer-btn strong { display: block; font-size: 1.02rem; }
.answer-btn small { color: var(--muted); display: block; margin-top: 4px; }
.answer-btn.correct { border-color: rgba(124,241,171,0.8); background: rgba(124,241,171,0.16); }
.answer-btn.incorrect { border-color: rgba(255,139,139,0.7); background: rgba(255,139,139,0.14); }
.answer-btn:disabled { cursor: default; opacity: 0.95; }
.quiz-actions, .results-actions, .reset-zone { display: flex; gap: 12px; margin-top: 16px; flex-wrap: wrap; }
.feedback { margin-top: 14px; padding: 18px; }
.hidden { display: none; }
.feedback.good { border-color: rgba(124,241,171,0.8); }
.feedback.bad { border-color: rgba(255,139,139,0.8); }
.results-card { max-width: 780px; margin: 0 auto; }
.results-card p { color: var(--muted); }
.results-card h2 { font-size: clamp(2rem, 6vw, 3rem); margin: 8px 0 10px; }
.overlay-screen.active { display: grid; position: fixed; inset: 0; padding: 18px; background: rgba(2, 7, 16, 0.8); backdrop-filter: blur(8px); overflow: auto; z-index: 50; }
.overlay { width: min(100%, 1100px); margin: auto; }
.locker-section { margin-top: 18px; }
.locker-section p { color: var(--muted); margin-top: 6px; }
.locker-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(110px, 1fr)); gap: 12px; margin-top: 16px; }
.locker-card { border: 1px solid var(--line); border-radius: 18px; padding: 10px; background: rgba(255,255,255,0.05); text-align: center; }
.locker-card img { width: 72px; margin: 0 auto 8px; }
.locker-card small { color: var(--muted); display: block; }
.locker-card.locked { opacity: 0.65; }
@media (max-width: 900px) {
  .hero-card, .kit-stage { grid-template-columns: 1fr; }
  .mode-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .topbar, .quiz-head, .overlay-head { align-items: flex-start; flex-direction: column; }
  .hero-stats, .results-stats, .progress-grid, .answers-grid { grid-template-columns: 1fr; }
  .mode-grid { grid-template-columns: 1fr; }
  .app-shell { padding: 14px 12px 30px; }
}