:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-2: #eef1f5;
  --text: #16191d;
  --muted: #5b6470;
  --line: #dde2e8;
  --accent: #3b6ea8;
  --accent-ink: #ffffff;
  --accent-soft: #e3ecf7;
  --ok: #2f8a57;
  --win-bar: #e9ecf0;
  --win-bg: #fbfbfc;
  --shadow: 0 18px 50px rgba(20, 30, 45, .14);
  --radius: 14px;
  --font: "Pretendard", -apple-system, "Segoe UI", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "Cascadia Mono", Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1216;
    --surface: #161a20;
    --surface-2: #1d222a;
    --text: #e8ebef;
    --muted: #9aa4b1;
    --line: #2a313b;
    --accent: #6d9fd8;
    --accent-ink: #0c1118;
    --accent-soft: #1c2a3b;
    --ok: #5cc28a;
    --win-bar: #20252d;
    --win-bg: #181c22;
    --shadow: 0 18px 50px rgba(0, 0, 0, .45);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
html, body { overflow-x: clip; }
body {
  word-break: keep-all;
  overflow-wrap: break-word;
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); }
code { font-family: var(--mono); font-size: .9em; background: var(--surface-2); padding: .1em .35em; border-radius: 5px; }

/* 언어: 한쪽만 보인다 */
html[data-lang="ko"] [lang="en"]:not(html) { display: none !important; }
html[data-lang="en"] [lang="ko"]:not(html) { display: none !important; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

/* 상단 */
.topbar {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar .wrap { display: flex; align-items: center; gap: 20px; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--text); text-decoration: none; letter-spacing: -.01em; }
.brand img { width: 26px; height: 26px; border-radius: 6px; }
.brand small { font-weight: 500; color: var(--muted); }
.nav { display: flex; gap: 18px; margin-left: auto; }
.nav a { color: var(--muted); text-decoration: none; font-size: 15px; }
.nav a:hover { color: var(--text); }
.lang-toggle { display: flex; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; }
.lang-toggle button {
  border: 0; background: transparent; color: var(--muted);
  font: 600 13px var(--font); padding: 5px 10px; cursor: pointer;
}
.lang-toggle button.active { background: var(--accent); color: var(--accent-ink); }

/* 첫 화면 */
.hero { padding: 72px 0 40px; }
.hero .wrap > *, .cols > *, .install > *, .features > *, .steps > *, .modes > * { min-width: 0; }
.hero .wrap { display: grid; grid-template-columns: 1fr 1.1fr; gap: 48px; align-items: center; }
.eyebrow { font: 600 12px/1 var(--mono); letter-spacing: .12em; color: var(--accent); text-transform: uppercase; margin: 0 0 16px; }
h1 { font-size: clamp(32px, 4.6vw, 48px); line-height: 1.18; letter-spacing: -.025em; margin: 0 0 18px; }
.lead { font-size: 18px; color: var(--muted); margin: 0 0 28px; max-width: 34em; }
.cta { display: flex; flex-wrap: wrap; gap: 10px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 18px; border-radius: 10px; font-weight: 600; font-size: 15px;
  text-decoration: none; border: 1px solid var(--line); color: var(--text); background: var(--surface);
}
.btn:hover { border-color: var(--accent); }
.btn.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.btn.disabled { opacity: .55; pointer-events: none; }
.btn svg { width: 18px; height: 18px; }
.fine { margin: 16px 0 0; font-size: 13px; color: var(--muted); }

/* 앱 창 모형 (데모 데이터) */
.app-window {
  background: var(--win-bg); border: 1px solid var(--line); border-radius: 12px;
  box-shadow: var(--shadow); overflow: hidden; font-size: 12.5px;
}
.app-titlebar { display: flex; align-items: center; gap: 8px; padding: 9px 12px; background: var(--win-bar); border-bottom: 1px solid var(--line); }
.app-titlebar img { width: 16px; height: 16px; border-radius: 4px; }
.app-titlebar span { color: var(--muted); }
.app-titlebar .dots { margin-left: auto; display: flex; gap: 14px; color: var(--muted); font-size: 11px; }
.app-menu { display: flex; gap: 14px; padding: 7px 12px; border-bottom: 1px solid var(--line); color: var(--text); white-space: nowrap; overflow: hidden; }
.app-tabs { display: flex; gap: 2px; padding: 6px 10px 0; border-bottom: 1px solid var(--line); }
.app-tabs span { padding: 5px 12px; border-radius: 6px 6px 0 0; color: var(--muted); }
.app-tabs span.on { background: var(--surface); color: var(--text); border: 1px solid var(--line); border-bottom-color: var(--surface); margin-bottom: -1px; }
.app-body { background: var(--surface); padding: 6px 0 10px; }
.app-row { display: grid; grid-template-columns: 18px 1.4fr .8fr .5fr; gap: 10px; padding: 4px 14px; white-space: nowrap; }
.app-row > * { overflow: hidden; text-overflow: ellipsis; }
.app-row.head { color: var(--muted); border-bottom: 1px solid var(--line); padding-bottom: 6px; margin-bottom: 4px; }
.app-row.group { grid-template-columns: 18px 1fr; font-weight: 600; padding-top: 8px; }
.app-row .mono { font-family: var(--mono); font-size: 11.5px; color: var(--muted); }
.tag { display: inline-block; padding: 0 6px; border-radius: 5px; background: var(--accent-soft); color: var(--accent); font-size: 11px; }
.app-status { padding: 7px 12px; border-top: 1px solid var(--line); color: var(--muted); background: var(--win-bar); }

/* 구역 */
section { padding: 56px 0; }
section.alt { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
h2 { font-size: clamp(24px, 3vw, 32px); letter-spacing: -.02em; line-height: 1.25; margin: 0 0 10px; }
.sub { color: var(--muted); margin: 0 0 32px; max-width: 46em; }

.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; counter-reset: step; }
.step { background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
section:not(.alt) .step { background: var(--surface); }
.step::before {
  counter-increment: step; content: counter(step);
  display: inline-grid; place-items: center; width: 28px; height: 28px; border-radius: 50%;
  background: var(--accent); color: var(--accent-ink); font-weight: 700; font-size: 14px; margin-bottom: 12px;
}
.step h3 { margin: 0 0 6px; font-size: 17px; }
.step p { margin: 0; color: var(--muted); font-size: 15px; }

.features { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px 28px; }
.feature { display: grid; grid-template-columns: 36px 1fr; gap: 12px; padding: 14px 0; border-bottom: 1px solid var(--line); }
.feature .ico { width: 36px; height: 36px; border-radius: 9px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; }
.feature .ico svg { width: 19px; height: 19px; }
.feature h3 { margin: 0 0 2px; font-size: 16px; }
.feature p { margin: 0; color: var(--muted); font-size: 15px; }

.modes { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.mode { border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; background: var(--bg); }
.mode b { display: block; margin-bottom: 4px; }
.mode p { margin: 0; color: var(--muted); font-size: 14.5px; }
.mode .default { font: 600 11px var(--mono); color: var(--ok); margin-left: 6px; }

.cols { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
ul.plain { margin: 0; padding-left: 1.1em; color: var(--muted); }
ul.plain li { margin: 6px 0; }
ul.plain li b { color: var(--text); font-weight: 600; }

.install { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.card { border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; background: var(--surface); }
.card h3 { margin: 0 0 6px; }
.card p { margin: 0 0 14px; color: var(--muted); font-size: 15px; }

/* 문서 페이지 (개인정보 처리방침) */
.doc { padding: 48px 0 64px; }
.doc .wrap { max-width: 760px; }
.doc h1 { font-size: clamp(28px, 4vw, 38px); }
.doc h2 { font-size: 21px; margin: 36px 0 10px; }
.doc p, .doc li { color: var(--text); }
.doc .meta { color: var(--muted); margin: 0 0 24px; }
.doc .summary { background: var(--accent-soft); border-radius: var(--radius); padding: 16px 20px; margin: 0 0 8px; }

footer { padding: 32px 0 48px; color: var(--muted); font-size: 14px; border-top: 1px solid var(--line); }
footer .wrap { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; }
footer a { color: var(--muted); }

@media (max-width: 860px) {
  .hero { padding: 40px 0 24px; }
  .hero .wrap, .cols, .install { grid-template-columns: 1fr; gap: 28px; }
  .steps, .modes, .features { grid-template-columns: 1fr; }
  .nav { display: none; }
  .lang-toggle { margin-left: auto; }
  .wrap { padding: 0 16px; }
  .app-row { grid-template-columns: 18px 1.4fr .9fr; }
  .app-row > :nth-child(4) { display: none; }
}