:root {
  --bg: #0b0f14;
  --panel: #121923;
  --panel-2: #182231;
  --line: #263447;
  --text: #f6f8fb;
  --muted: #aab6c5;
  --accent: #76e6c2;
  --accent-soft: rgba(118, 230, 194, 0.12);
  --warning: #ffcf70;
  font-family: Inter, Pretendard, "Noto Sans KR", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 85% -10%, rgba(56, 189, 248, 0.13), transparent 34rem),
    radial-gradient(circle at 0% 10%, rgba(118, 230, 194, 0.09), transparent 30rem),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
}

button { font: inherit; }

.page-shell {
  width: min(1040px, calc(100% - 32px));
  margin: 0 auto;
  padding: 64px 0 48px;
}

.hero {
  padding: 36px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: linear-gradient(145deg, rgba(24, 34, 49, 0.96), rgba(13, 20, 30, 0.96));
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.24);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

h1 { margin: 0; font-size: clamp(2rem, 5vw, 3.7rem); line-height: 1.08; letter-spacing: -0.045em; }
.hero-copy { max-width: 760px; margin: 18px 0 0; color: var(--muted); font-size: 1.05rem; line-height: 1.7; }

.metrics {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin-top: 30px;
}

.metric { padding: 16px; border: 1px solid var(--line); border-radius: 16px; background: rgba(5, 9, 14, 0.3); }
.metric strong { display: block; font-size: 1.2rem; }
.metric span { display: block; margin-top: 6px; color: var(--muted); font-size: 0.78rem; }

.tabs {
  position: sticky;
  top: 12px;
  z-index: 3;
  display: inline-flex;
  gap: 6px;
  margin: 24px 0;
  padding: 6px;
  border: 1px solid var(--line);
  border-radius: 15px;
  background: rgba(11, 15, 20, 0.9);
  backdrop-filter: blur(16px);
}

.tab {
  border: 0;
  border-radius: 10px;
  padding: 11px 18px;
  color: var(--muted);
  background: transparent;
  cursor: pointer;
  font-weight: 750;
}
.tab:hover { color: var(--text); }
.tab.is-active { color: #07110e; background: var(--accent); }

.panel { display: grid; gap: 20px; }
.section-card { padding: 28px; border: 1px solid var(--line); border-radius: 22px; background: rgba(18, 25, 35, 0.88); }
.section-kicker { margin: 0 0 8px; color: var(--accent); font-size: 0.78rem; font-weight: 800; letter-spacing: 0.09em; }
.section-card h2 { margin: 0; font-size: 1.45rem; letter-spacing: -0.025em; }
.section-intro { margin: 12px 0 0; color: var(--muted); line-height: 1.7; }

.takeaway-grid, .contributor-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; margin-top: 22px; }
.takeaway, .contributor { padding: 20px; border: 1px solid var(--line); border-radius: 17px; background: var(--panel-2); }
.takeaway h3, .contributor h3 { margin: 0; font-size: 1.03rem; }
.takeaway p, .contributor p { margin: 10px 0 0; color: var(--muted); line-height: 1.68; }
.source-line { margin-top: 13px; color: var(--accent); font-size: 0.78rem; font-weight: 700; }

.topic-chips { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 14px; }
.chip { padding: 6px 9px; border-radius: 999px; color: var(--accent); background: var(--accent-soft); font-size: 0.75rem; font-weight: 750; }

.topic-card { padding: 0; overflow: hidden; }
.topic-head { padding: 26px 28px 18px; }
.tip-list { list-style: none; margin: 0; padding: 0 28px 26px; display: grid; gap: 12px; }
.tip-item { position: relative; padding: 16px 18px 16px 45px; border: 1px solid var(--line); border-radius: 15px; color: #dfe7f1; line-height: 1.65; background: rgba(6, 10, 16, 0.3); }
.tip-item::before { content: "✓"; position: absolute; left: 17px; top: 16px; color: var(--accent); font-weight: 900; }
.tip-source { display: block; margin-top: 7px; color: var(--muted); font-size: 0.75rem; }
.caution { margin: 0 28px 26px; padding: 14px 16px; border-left: 3px solid var(--warning); color: #ead9b6; background: rgba(255, 207, 112, 0.08); line-height: 1.6; }

footer { margin-top: 28px; padding: 18px 2px; color: var(--muted); font-size: 0.78rem; line-height: 1.6; }
.error { padding: 40px; border: 1px solid #7f1d1d; border-radius: 20px; background: #2b1010; }

@media (max-width: 760px) {
  .page-shell { width: min(100% - 20px, 1040px); padding-top: 18px; }
  .hero { padding: 25px 20px; border-radius: 21px; }
  .metrics { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .tabs { top: 8px; width: 100%; }
  .tab { flex: 1; }
  .section-card { padding: 22px 18px; }
  .takeaway-grid, .contributor-grid { grid-template-columns: 1fr; }
  .topic-head { padding: 22px 18px 16px; }
  .tip-list { padding: 0 18px 20px; }
  .caution { margin: 0 18px 20px; }
}