:root {
  color-scheme: light dark;
  --bg: #f5f7fb;
  --surface: #ffffff;
  --line: rgba(60, 60, 67, .18);
  --text: #1c1c1e;
  --muted: #636366;
  --quiet: #8e8e93;
  --accent: #007aff;
  --accent-soft: rgba(0, 122, 255, .10);
  --button-text: #ffffff;
  --nav-active: rgba(0, 0, 0, .05);
  --menu-shadow: rgba(0, 0, 0, .14);
  font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  background: var(--bg);
  color: var(--text);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --surface: #1c1c1e;
    --line: rgba(84, 84, 88, .65);
    --text: #f2f2f7;
    --muted: #aeaeb2;
    --quiet: #8e8e93;
    --accent: #0a84ff;
    --accent-soft: rgba(10, 132, 255, .16);
    --nav-active: rgba(255, 255, 255, .08);
    --menu-shadow: rgba(0, 0, 0, .45);
  }
}

* { box-sizing: border-box; }
html { min-width: 320px; background: var(--bg); }
body { margin: 0; min-height: 100vh; background: var(--bg); }
a { color: inherit; }
.page { width: min(760px, calc(100% - 36px)); margin: 0 auto; padding: 58px 0 80px; }
.header { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 64px; }
.brand { color: var(--text); text-decoration: none; }
.brand-name { font-weight: 750; letter-spacing: -.02em; }
.header-actions { display: flex; align-items: center; gap: 8px; }
.nav { display: flex; gap: 4px; }
.nav a { padding: 9px 11px; border-radius: 8px; color: var(--muted); text-decoration: none; font-size: 14px; }
.nav a:hover, .nav a[aria-current="page"] { background: var(--nav-active); color: var(--text); }
.language-picker { position: relative; }
.language-picker summary { min-width: 78px; padding: 9px 28px 9px 11px; border: 1px solid var(--line); border-radius: 8px; color: var(--muted); cursor: pointer; font-size: 14px; list-style: none; }
.language-picker summary::-webkit-details-marker { display: none; }
.language-picker summary::after { content: "⌄"; position: absolute; right: 10px; top: 8px; color: var(--quiet); }
.language-picker[open] summary { color: var(--text); border-color: var(--quiet); }
.language-menu { position: absolute; z-index: 2; top: calc(100% + 7px); right: 0; min-width: 130px; padding: 6px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); box-shadow: 0 16px 38px var(--menu-shadow); }
.language-menu a { display: block; padding: 9px 10px; border-radius: 7px; color: var(--muted); text-decoration: none; font-size: 14px; }
.language-menu a:hover, .language-menu a[aria-current="true"] { background: var(--accent-soft); color: var(--accent); }
.eyebrow { margin: 0 0 11px; color: var(--accent); font: 700 11px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: .14em; }
h1 { margin: 0; max-width: 620px; font-size: clamp(34px, 7vw, 56px); line-height: 1.08; letter-spacing: -.05em; }
.lead { margin: 22px 0 0; max-width: 640px; color: var(--muted); font-size: 18px; line-height: 1.75; }
.support-card { margin-top: 42px; padding: clamp(22px, 4vw, 32px); border: 1px solid var(--line); border-radius: 16px; background: var(--surface); }
.support-card h2 { margin: 0 0 9px; font-size: 17px; }
.support-card p { margin: 0; color: var(--muted); line-height: 1.7; }
.email { display: inline-flex; margin-top: 22px; padding: 12px 16px; border-radius: 9px; background: var(--accent); color: var(--button-text); text-decoration: none; font-weight: 760; }
.email:hover { filter: brightness(1.07); }
.note { margin-top: 17px !important; color: var(--quiet) !important; font-size: 13px; }
.policy { margin-top: 45px; }
.policy section { padding: 27px 0; border-top: 1px solid var(--line); }
.policy h2 { margin: 0 0 13px; font-size: 19px; letter-spacing: -.02em; }
.policy p { margin: 9px 0 0; color: var(--muted); font-size: 16px; line-height: 1.82; }
.policy a { color: var(--accent); }
.footer { margin-top: 52px; padding-top: 22px; border-top: 1px solid var(--line); color: var(--quiet); font-size: 13px; }

a:focus-visible, summary:focus-visible { outline: 3px solid var(--accent-soft); outline-offset: 3px; }

@media (max-width: 560px) {
  .page { padding-top: 28px; }
  .header { margin-bottom: 44px; align-items: flex-start; }
  .header-actions { align-items: flex-end; flex-direction: column-reverse; gap: 6px; }
  .nav { gap: 2px; }
  .nav a { padding: 9px 8px; font-size: 13px; }
  .language-picker summary { min-width: 88px; padding-block: 7px; font-size: 13px; }
  .language-picker summary::after { top: 6px; }
  .lead { font-size: 16px; }
}