:root {
  --brand: #3563E9;
  --brand-2: #6C8FF7;
  --ink: #0D1220;
  --ink-2: #414A5E;
  --ink-3: #6B7488;
  --bg: #FFFFFF;
  --bg-soft: #F5F7FC;
  --line: #E7EBF3;
  --th-bg: #F5F7FC;
  --header-bg: rgba(255, 255, 255, .82);
  --shadow-sm: 0 2px 8px rgba(30, 58, 138, .06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --brand: #6C8FF7;
    --brand-2: #8BA8FF;
    --ink: #F2F5FC;
    --ink-2: #B9C1D4;
    --ink-3: #8791A8;
    --bg: #0B1020;
    --bg-soft: #0F1730;
    --line: #23304F;
    --th-bg: #131C36;
    --header-bg: rgba(11, 16, 32, .82);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, .3);
  }
}

/* 앱에서 전달한 테마(?theme)가 시스템 설정을 항상 이긴다 */
:root[data-theme="light"] {
  --brand: #3563E9;
  --brand-2: #6C8FF7;
  --ink: #0D1220;
  --ink-2: #414A5E;
  --ink-3: #6B7488;
  --bg: #FFFFFF;
  --bg-soft: #F5F7FC;
  --line: #E7EBF3;
  --th-bg: #F5F7FC;
  --header-bg: rgba(255, 255, 255, .82);
  --shadow-sm: 0 2px 8px rgba(30, 58, 138, .06);
}

:root[data-theme="dark"] {
  --brand: #6C8FF7;
  --brand-2: #8BA8FF;
  --ink: #F2F5FC;
  --ink-2: #B9C1D4;
  --ink-3: #8791A8;
  --bg: #0B1020;
  --bg-soft: #0F1730;
  --line: #23304F;
  --th-bg: #131C36;
  --header-bg: rgba(11, 16, 32, .82);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, .3);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Apple SD Gothic Neo', 'Pretendard',
    'Segoe UI', 'Noto Sans KR', Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
}

a { color: var(--brand); text-decoration: none; }
img { display: block; max-width: 100%; }

.wrap { width: 100%; max-width: 760px; margin: 0 auto; padding: 0 22px; }

/* ---------- Header ---------- */
header {
  position: sticky; top: 0; z-index: 50;
  background: var(--header-bg);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 62px; }
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 800; font-size: 18px; letter-spacing: -.02em; color: var(--ink);
}
.brand img { width: 30px; height: 30px; border-radius: 9px; box-shadow: var(--shadow-sm); }
.lang {
  background: none; border: 1px solid var(--line); color: var(--ink-2);
  font-family: inherit; font-size: 13.5px; font-weight: 700; cursor: pointer;
  padding: 8px 16px; border-radius: 999px; white-space: nowrap;
  transition: color .2s, border-color .2s;
}
.lang:hover { color: var(--brand); border-color: var(--brand-2); }

/* ---------- Content ---------- */
main { padding: 40px 0 96px; }

h1 { font-size: clamp(28px, 5vw, 34px); font-weight: 850; letter-spacing: -.025em; line-height: 1.2; }
h2 {
  font-size: 19px; font-weight: 750; letter-spacing: -.01em;
  margin: 40px 0 10px; padding-top: 26px; border-top: 1px solid var(--line);
}
h3 { font-size: 15px; font-weight: 700; margin: 20px 0 6px; color: var(--ink); }

p, li { font-size: 14.5px; color: var(--ink-2); }
p { margin-top: 8px; }
ul { padding-left: 20px; margin-top: 6px; }
li { margin: 4px 0; }

.meta { color: var(--ink-3); font-size: 13.5px; margin: 12px 0 28px; }

/* 인트로 문단(첫 섹션 전) */
.meta + p { color: var(--ink-2); }

table {
  border-collapse: collapse; width: 100%; margin: 12px 0;
  font-size: 13.5px; border: 1px solid var(--line); border-radius: 12px; overflow: hidden;
}
th, td {
  border-bottom: 1px solid var(--line); padding: 10px 12px;
  text-align: left; vertical-align: top; color: var(--ink-2);
}
th { background: var(--th-bg); font-weight: 700; color: var(--ink); }
tr:last-child td { border-bottom: none; }

.footer {
  margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--line);
  color: var(--ink-3); font-size: 12.5px; line-height: 1.7;
}

/* ---------- Site footer ---------- */
footer.site {
  border-top: 1px solid var(--line); padding: 28px 0;
  color: var(--ink-3); font-size: 13.5px; text-align: center;
}
footer.site a { color: var(--ink-3); font-weight: 600; }
footer.site a:hover { color: var(--brand); }

@media (max-width: 520px) {
  .brand img { display: none; }
}