/* 머스트체크 랜딩.
 *
 * 🔴 앱 화면(카카오톡 톤)과 **일부러 다르게** 간다.
 *    앱은 매일 쓰는 도구라 익숙함이 최우선이지만, 랜딩은 처음 온 사람에게
 *    "이거 제대로 만든 프로그램이네" 를 3초 안에 납득시켜야 한다.
 *    브랜드가 MUSTCHECK 로 정해진 이유(전문성)를 화면이 뒷받침해야 한다.
 *
 * 색은 심볼에서 그대로 가져온다(brand/README.md).
 */

:root {
  --navy: #071b4d;
  --royal: #1458e8;
  --bright: #168bff;
  --cyan: #20d5f5;

  --ink: #0d1b34;
  --muted: #5b6675;
  --line: #e3e7ee;
  --bg: #ffffff;
  --bg-soft: #f5f8fc;

  --wrap: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Pretendard", "Malgun Gothic", -apple-system, BlinkMacSystemFont,
    "Segoe UI", system-ui, sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img, svg { max-width: 100%; }
a { color: inherit; }

.wrap {
  width: min(100% - 40px, var(--wrap));
  margin-inline: auto;
}

/* ── 상단바 ─────────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, .88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-in {
  display: flex;
  align-items: center;
  gap: 12px;
  height: 62px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -.3px;
}
.brand .mark { width: 26px; height: 26px; flex: 0 0 auto; }
.brand .ko {
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: 0;
}
.nav .spacer { flex: 1 1 auto; }

/* ── 버튼 ───────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 12px;
  background: var(--royal);
  color: #fff;
  font-weight: 700;
  font-size: 15px;
  text-decoration: none;
  border: 0;
  cursor: pointer;
  transition: background .15s, transform .1s;
}
.btn:hover { background: #0f47c4; }
.btn:active { transform: translateY(1px); }
.btn.sm { padding: 9px 18px; font-size: 13.5px; border-radius: 10px; }
.btn.ghost {
  background: transparent;
  color: var(--royal);
  border: 1px solid #c8d6f2;
}
.btn.ghost:hover { background: #f0f5ff; }

/* ── 히어로 ─────────────────────────────── */
.hero {
  position: relative;
  padding: 84px 0 76px;
  background:
    radial-gradient(1100px 460px at 78% -8%, #e8f1ff 0%, rgba(232, 241, 255, 0) 62%),
    var(--bg);
  overflow: hidden;
}
.hero h1 {
  margin: 0 0 18px;
  font-size: clamp(30px, 4.6vw, 50px);
  line-height: 1.22;
  letter-spacing: -1.4px;
  font-weight: 800;
}
.eyebrow {
  display: inline-block;
  margin-bottom: 18px;
  padding: 6px 13px;
  border-radius: 999px;
  background: #e8f1ff;
  color: var(--royal);
  font-size: 13px;
  font-weight: 700;
}
.lead {
  margin: 0 0 10px;
  font-size: clamp(16px, 1.7vw, 18.5px);
  color: var(--muted);
  max-width: 30em;
}
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.hero-note { margin-top: 14px; font-size: 13px; color: var(--muted); }

/* ── 섹션 공통 ──────────────────────────── */
section { padding: 74px 0; }
section.soft { background: var(--bg-soft); border-block: 1px solid var(--line); }
h2 {
  margin: 0 0 12px;
  font-size: clamp(23px, 2.8vw, 31px);
  letter-spacing: -.9px;
  font-weight: 800;
}
.sub { margin: 0 0 34px; color: var(--muted); font-size: 16px; }

/* ── 카드 ───────────────────────────────── */
.cards {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(255px, 1fr));
}
.card {
  padding: 26px 24px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
}
.card h3 { margin: 14px 0 8px; font-size: 17px; letter-spacing: -.4px; }
.card p { margin: 0; color: var(--muted); font-size: 14.5px; }
.card .ico {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border-radius: 11px;
  background: #e8f1ff;
  color: var(--royal);
}
.card .ico svg { width: 21px; height: 21px; fill: currentColor; }

/* ── 카페 목록 ──────────────────────────── */
.cafes { display: flex; flex-wrap: wrap; gap: 9px; }
.cafes a {
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-size: 14px;
  text-decoration: none;
  color: var(--ink);
}
.cafes a:hover { border-color: var(--royal); color: var(--royal); }

/* ── FAQ ────────────────────────────────── */
.faq { display: grid; gap: 12px; max-width: 780px; }
.faq details {
  border: 1px solid var(--line);
  border-radius: 13px;
  background: #fff;
  padding: 16px 20px;
}
.faq summary {
  cursor: pointer;
  font-weight: 700;
  font-size: 15.5px;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: " +"; color: var(--royal); }
.faq details[open] summary::after { content: " −"; }
.faq p { margin: 12px 0 0; color: var(--muted); font-size: 14.5px; }

/* ── 마무리 CTA ─────────────────────────── */
.final {
  text-align: center;
  background: linear-gradient(160deg, var(--navy) 0%, #0d2f7a 55%, var(--royal) 100%);
  color: #fff;
  border: 0;
}
.final h2 { color: #fff; }
.final .sub { color: #c3d6f7; }
.final .btn { background: #fff; color: var(--royal); }
.final .btn:hover { background: #eef4ff; }

/* ── 푸터 ───────────────────────────────── */
footer {
  padding: 34px 0 46px;
  border-top: 1px solid var(--line);
  font-size: 13.5px;
  color: var(--muted);
}
footer a { color: var(--muted); }
.foot-row { display: flex; flex-wrap: wrap; gap: 8px 18px; align-items: center; }

/* 사업자 정보 — 광고주 계정(청개구리소프트)과 일치해야 심사를 통과한다. */
.foot-legal {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.foot-legal p { margin: 3px 0; font-size: 12.5px; line-height: 1.7; color: #8994a5; }
.foot-disc { margin-top: 10px !important; }
.foot-copy { margin-top: 8px !important; color: #aab4b8; font-size: 12px; }

@media (max-width: 640px) {
  .hero { padding: 56px 0 50px; }
  section { padding: 54px 0; }
}