:root {
  --bg: #080908;
  --bg-surface: #111412;
  --bg-card: #151a17;
  --gold: #c79a51;
  --gold-light: #e5b974;
  --gold-dim: rgba(199, 154, 81, 0.15);
  --paper: #e5e2da;
  --paper-dim: #a6a297;
  --muted: #6b6962;
  --line: rgba(236, 232, 223, 0.1);
  --line-gold: rgba(199, 154, 81, 0.35);
  --font-serif: "Noto Serif KR", "Batang", serif;
  --font-sans: "Pretendard", "Inter", -apple-system, sans-serif;
  --font-display: "Outfit", "Inter", sans-serif;
  --font-mono: "JetBrains Mono", monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--paper);
  font-family: var(--font-sans);
  line-height: 1.7;
  overflow-x: hidden;
}

/* Nav */
.campus-nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; justify-content: space-between; align-items: center;
  padding: 18px 4.5vw;
  background: rgba(8, 9, 8, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: baseline; gap: 12px; text-decoration: none; }
.brand-en { font-family: var(--font-display); font-size: 14px; font-weight: 700; letter-spacing: 0.24em; color: var(--gold); }
.brand-ko { font-family: var(--font-serif); font-size: 12px; color: var(--paper-dim); letter-spacing: -0.04em; }
.brand-badge {
  font-family: var(--font-display); font-size: 9px; letter-spacing: 0.18em;
  color: var(--gold-light); background: var(--gold-dim); border: 1px solid var(--line-gold);
  padding: 2px 8px; border-radius: 2px;
}
.nav-links { display: flex; align-items: center; gap: 20px; }
.nav-links a {
  font-family: var(--font-display); font-size: 11px; letter-spacing: 0.15em;
  color: var(--paper-dim); text-decoration: none; transition: color 0.2s;
}
.nav-links a:hover { color: var(--gold); }
.nav-cta-btn {
  border: 1px solid var(--line-gold) !important; padding: 8px 16px !important;
  color: var(--gold) !important; font-size: 10px !important; transition: all 0.3s !important;
}
.nav-cta-btn:hover { background: var(--gold) !important; color: #080908 !important; }

.container { max-width: 1140px; margin: 0 auto; padding: 140px 24px 80px; }

/* Hero */
.hero-section { text-align: center; margin-bottom: 64px; }
.badge-pill {
  display: inline-block; font-family: var(--font-display); font-size: 10px; letter-spacing: 0.2em;
  color: var(--gold-light); background: var(--gold-dim); border: 1px solid var(--line-gold);
  padding: 5px 16px; border-radius: 2px; margin-bottom: 20px;
}
.hero-title {
  font-family: var(--font-serif); font-size: clamp(28px, 4vw, 46px); color: #fff;
  font-weight: 400; margin-bottom: 18px; line-height: 1.35;
}
.hero-title span { color: var(--gold); }
.hero-desc { font-size: 15px; color: var(--paper-dim); max-width: 740px; margin: 0 auto; line-height: 1.85; }

/* Common Card Section */
.card-section {
  background: var(--bg-surface); border: 1px solid var(--line);
  padding: 48px 40px; border-radius: 2px; margin-bottom: 48px;
}
.card-header { margin-bottom: 32px; }
.card-header.center { text-align: center; }
.step-badge {
  font-family: var(--font-display); font-size: 11px; letter-spacing: 0.22em;
  color: var(--gold); margin-bottom: 8px; display: inline-block; font-weight: 600;
}
.card-header h2 { font-family: var(--font-serif); font-size: 24px; color: #fff; font-weight: 400; margin-bottom: 8px; }
.section-subtitle { font-size: 13px; color: var(--paper-dim); line-height: 1.6; }

/* STEP 01: Quiz */
.quiz-container { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-bottom: 24px; }
.quiz-card {
  background: #0d100e; border: 1px solid var(--line); padding: 26px 20px;
  cursor: pointer; transition: all 0.3s; position: relative; border-radius: 2px;
}
.quiz-card:hover { border-color: var(--gold); transform: translateY(-4px); }
.quiz-card.selected-correct { border-color: #22c55e !important; background: rgba(34, 197, 94, 0.08) !important; }
.quiz-card.selected-wrong { border-color: #ef4444 !important; background: rgba(239, 68, 68, 0.08) !important; }
.quiz-role { font-family: var(--font-mono); font-size: 11px; color: var(--gold); margin-bottom: 12px; letter-spacing: 0.1em; }
.quiz-text { font-size: 13px; color: #cec9bd; line-height: 1.75; }

.result-box {
  background: rgba(199, 154, 81, 0.06); border: 1px solid var(--line-gold);
  padding: 24px 28px; display: flex; gap: 20px; align-items: flex-start;
}
.result-box.hidden { display: none; }
.result-badge {
  font-family: var(--font-display); font-size: 10px; font-weight: 700; letter-spacing: 0.15em;
  padding: 4px 10px; background: var(--gold); color: #080908; border-radius: 2px;
}
.result-content h4 { font-size: 16px; color: #fff; margin-bottom: 6px; }
.result-content p { font-size: 13px; color: var(--paper-dim); line-height: 1.75; }

/* STEP 02: 3D Flip Card */
.flip-container { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.flip-card { height: 280px; perspective: 1000px; }
.flip-card-inner {
  position: relative; width: 100%; height: 100%; text-align: left;
  transition: transform 0.7s cubic-bezier(0.4, 0, 0.2, 1); transform-style: preserve-3d;
}
.flip-card:hover .flip-card-inner { transform: rotateY(180deg); }
.flip-card-front, .flip-card-back {
  position: absolute; width: 100%; height: 100%; backface-visibility: hidden;
  border-radius: 2px; padding: 36px 30px; display: flex; flex-direction: column; justify-content: space-between;
  border: 1px solid var(--line);
}
.flip-card-front { background: #0d100e; }
.card-tag { font-family: var(--font-mono); font-size: 11px; color: var(--gold); letter-spacing: 0.15em; }
.flip-card-front h3 { font-size: 19px; color: #fff; margin: 12px 0 8px; font-weight: 600; }
.flip-card-front p { font-size: 13px; color: var(--paper-dim); line-height: 1.7; }
.action-hint { font-size: 11px; color: var(--gold); font-family: var(--font-display); letter-spacing: 0.1em; }

.flip-card-back { background: #141916; transform: rotateY(180deg); border-color: var(--line-gold); }
.flip-card-back h3 { font-size: 18px; color: #fff; margin: 10px 0; }
.back-desc { font-size: 13px; color: #cec9bd; line-height: 1.75; }

/* STEP 03: Diagnosis & Needle Gauge */
.diagnosis-grid { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 32px; align-items: center; }
.check-list { display: flex; flex-direction: column; gap: 12px; }
.check-item {
  display: flex; align-items: center; gap: 14px; padding: 14px 18px;
  background: #0d100e; border: 1px solid var(--line); cursor: pointer;
  transition: all 0.25s; border-radius: 2px;
}
.check-item:hover { border-color: var(--line-gold); }
.check-item input[type="checkbox"] { display: none; }
.custom-chk {
  width: 18px; height: 18px; border: 1px solid var(--muted); border-radius: 2px;
  position: relative; flex-shrink: 0; transition: all 0.2s;
}
.check-item input[type="checkbox"]:checked + .custom-chk {
  background: var(--gold); border-color: var(--gold);
}
.check-item input[type="checkbox"]:checked + .custom-chk::after {
  content: '✓'; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  font-size: 11px; color: #080908; font-weight: 700;
}
.chk-text { font-size: 13px; color: #cec9bd; line-height: 1.6; }
.check-item.checked-item { background: rgba(199, 154, 81, 0.05); border-color: var(--gold); }
.check-item.checked-item .chk-text { color: #fff; }

/* Analog Gauge Widget */
.gauge-card {
  background: #0d100e; border: 1px solid var(--line-gold); padding: 36px 28px;
  text-align: center; border-radius: 2px; display: flex; flex-direction: column; align-items: center;
}
.gauge-header { font-family: var(--font-display); font-size: 11px; letter-spacing: 0.2em; color: var(--gold); margin-bottom: 20px; }
.gauge-dial {
  position: relative; width: 220px; height: 115px; margin: 0 auto 24px;
}
.gauge-needle {
  position: absolute; bottom: 15px; left: 108px; width: 4px; height: 78px;
  background: #fff; transform-origin: bottom center;
  transform: rotate(-90deg); transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 12px rgba(255, 255, 255, 0.8);
  border-radius: 2px;
  z-index: 5;
}
.gauge-center-cap {
  position: absolute; bottom: 6px; left: 100px; width: 20px; height: 20px;
  background: var(--gold); border-radius: 50%;
  border: 2px solid #080908;
  z-index: 6;
}
.gauge-score-wrap { display: flex; align-items: center; justify-content: center; gap: 12px; margin-bottom: 12px; }
.gauge-score { font-family: var(--font-mono); font-size: 32px; font-weight: 700; color: #fff; }
.gauge-status {
  font-family: var(--font-display); font-size: 11px; letter-spacing: 0.15em;
  padding: 4px 12px; border-radius: 2px; font-weight: 700;
}
.gauge-status.safe { background: rgba(34, 197, 94, 0.15); color: #4ade80; border: 1px solid rgba(34, 197, 94, 0.3); }
.gauge-status.warning { background: rgba(234, 179, 8, 0.15); color: #facc15; border: 1px solid rgba(234, 179, 8, 0.3); }
.gauge-status.danger { background: rgba(239, 68, 68, 0.15); color: #f87171; border: 1px solid rgba(239, 68, 68, 0.3); }
.gauge-desc { font-size: 12px; color: var(--paper-dim); line-height: 1.7; min-height: 48px; }

/* STEP 04: S-8 Principles with Watermark Numbers */
.principles-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.principle-card {
  position: relative; background: #0d100e; border: 1px solid var(--line);
  padding: 36px 30px; border-radius: 2px; overflow: hidden; transition: all 0.3s;
}
.principle-card:hover { border-color: var(--gold); transform: translateY(-3px); }
.watermark-num {
  position: absolute; right: 16px; bottom: 8px;
  font-family: var(--font-display); font-size: 84px; font-weight: 800;
  color: rgba(199, 154, 81, 0.05); line-height: 1; pointer-events: none;
  transition: color 0.3s;
}
.principle-card:hover .watermark-num { color: rgba(199, 154, 81, 0.12); }
.p-header { position: relative; z-index: 2; margin-bottom: 12px; }
.p-badge { font-family: var(--font-mono); font-size: 10px; color: var(--gold); letter-spacing: 0.15em; }
.p-title { font-size: 17px; font-weight: 600; color: #fff; margin-top: 4px; }
.p-desc { position: relative; z-index: 2; font-size: 13px; color: var(--paper-dim); line-height: 1.75; }

/* STEP 05: Core Questions */
.questions-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.q-box {
  background: #0d100e; border: 1px solid var(--line); padding: 32px 24px;
  border-radius: 2px; transition: all 0.3s;
}
.q-box:hover { border-color: var(--gold); }
.q-num { font-family: var(--font-mono); font-size: 10px; color: var(--gold); letter-spacing: 0.15em; margin-bottom: 10px; }
.q-title { font-size: 16px; font-weight: 600; color: #fff; line-height: 1.5; margin-bottom: 12px; }
.q-desc { font-size: 12px; color: var(--paper-dim); line-height: 1.75; }

/* Bottom CTA */
.bottom-cta-section {
  text-align: center; padding: 70px 40px; background: radial-gradient(circle at 50% 50%, rgba(199, 154, 81, 0.08), transparent 70%);
  border: 1px solid var(--line-gold); margin-top: 40px;
}
.cta-outline-btn {
  border: 1px solid var(--line-gold);
  color: var(--gold);
  background: transparent;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.16em;
  padding: 12px 24px;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
  cursor: pointer;
}
.cta-outline-btn:hover {
  background: var(--gold);
  color: var(--bg);
  border-color: var(--gold);
  box-shadow: 0 0 16px rgba(199, 154, 81, 0.35);
}

.footer { text-align: center; padding: 36px; font-size: 11px; color: var(--muted); border-top: 1px solid var(--line); }

@media (max-width: 900px) {
  .quiz-container, .flip-container, .diagnosis-grid, .principles-grid, .questions-grid { grid-template-columns: 1fr; }
  .flip-card { height: 250px; }
}