/* AutoDART 소개 사이트 */

:root {
  --navy: #1f3864;
  --navy-deep: #152747;
  --bg: #ffffff;
  --bg-alt: #f4f6fa;
  --surface: #ffffff;
  --text: #18202e;
  --muted: #5a6476;
  --border: #e1e6ee;
  --accent: #1f3864;
  --accent-hover: #2a4a82;
  --accent-text: #1f3864;
  --accent-soft: #e9eef7;
  --link: #24508f;
  --info-bg: #eef3fb;
  --info-border: #c9d7ee;
  --warn-bg: #fff6e8;
  --warn-border: #f0d4a6;
  --warn-text: #6b4a12;
  --kbd-bg: #f1f3f7;
  --shadow: 0 1px 2px rgba(16, 28, 52, 0.06), 0 8px 24px rgba(16, 28, 52, 0.06);
  --radius: 12px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Malgun Gothic", "맑은 고딕", "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  --mono: ui-monospace, "Cascadia Mono", Consolas, "D2Coding", monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e1420;
    --bg-alt: #131b2a;
    --surface: #182234;
    --text: #e4e9f1;
    --muted: #9ba6b8;
    --border: #273246;
    --accent: #3a64ad;
    --accent-hover: #4772bd;
    --accent-text: #a9c2ef;
    --accent-soft: #1d2a44;
    --link: #93b4ee;
    --info-bg: #17233a;
    --info-border: #2a3c5e;
    --warn-bg: #2a2214;
    --warn-border: #574320;
    --warn-text: #f0d29a;
    --kbd-bg: #222d42;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.25);
  }
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 72px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  word-break: keep-all;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: var(--link); text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }
h1, h2, h3 { line-height: 1.3; margin: 0; }
p { margin: 0 0 0.75em; }
p:last-child { margin-bottom: 0; }

code {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--kbd-bg);
  padding: 0.1em 0.4em;
  border-radius: 4px;
}

kbd {
  font-family: inherit;
  font-size: 0.9em;
  font-weight: 600;
  background: var(--kbd-bg);
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: 5px;
  padding: 0.05em 0.45em;
  white-space: nowrap;
}

.container { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 20px; }
.container.narrow { max-width: 820px; }

.skip-link {
  position: absolute; left: -9999px; top: 8px;
  background: var(--surface); color: var(--text); padding: 8px 12px; z-index: 100;
}
.skip-link:focus { left: 8px; }

:focus-visible { outline: 3px solid #6f95d8; outline-offset: 2px; }

/* 버튼 */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border-radius: 10px; font-weight: 700; text-decoration: none;
  padding: 12px 20px; border: 1px solid transparent; cursor: pointer;
  transition: background-color 0.15s, transform 0.15s, box-shadow 0.15s;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-sm { padding: 7px 14px; font-size: 14px; border-radius: 8px; }

/* 헤더 */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(1.4) blur(10px);
  -webkit-backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid var(--border);
}
.header-inner { display: flex; align-items: center; gap: 24px; height: 60px; }
.brand {
  display: flex; align-items: center; gap: 8px;
  color: var(--text); text-decoration: none; font-weight: 800; font-size: 18px; letter-spacing: -0.01em;
}
.site-nav { display: flex; gap: 4px; margin-left: auto; }
.site-nav a {
  color: var(--muted); text-decoration: none; font-size: 15px; font-weight: 500;
  padding: 6px 10px; border-radius: 6px;
}
.site-nav a:hover { color: var(--text); background: var(--bg-alt); }

/* 상단 */
.hero {
  background:
    radial-gradient(1000px 500px at 85% -10%, rgba(120, 160, 230, 0.22), transparent 60%),
    linear-gradient(160deg, var(--navy) 0%, var(--navy-deep) 100%);
  color: #fff;
  padding: 72px 0 80px;
}
.hero-inner { display: grid; grid-template-columns: 1.1fr 1fr; gap: 48px; align-items: center; }
.eyebrow {
  display: inline-block; font-size: 14px; font-weight: 600; letter-spacing: 0.02em;
  color: #c6d6f3; background: rgba(255, 255, 255, 0.08); border: 1px solid rgba(255, 255, 255, 0.16);
  padding: 4px 12px; border-radius: 999px; margin-bottom: 20px;
}
.hero h1 { font-size: clamp(32px, 5vw, 50px); font-weight: 800; letter-spacing: -0.025em; margin-bottom: 18px; }
.lead { font-size: 18px; color: #d6e0f2; max-width: 34em; margin-bottom: 28px; }

.hero-actions { margin-bottom: 24px; }
.btn-hero {
  background: #fff; color: var(--navy); font-size: 18px; padding: 15px 26px; border-radius: 12px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.22);
}
.btn-hero:hover { transform: translateY(-1px); box-shadow: 0 10px 26px rgba(0, 0, 0, 0.28); }
.download-meta { margin: 10px 0 0; font-size: 14px; color: #b9c8e3; min-height: 1.7em; }
.download-meta a { color: #fff; }

.hero-req { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 8px 20px; font-size: 14px; color: #d0dbef; }
.hero-req li { display: flex; align-items: center; gap: 6px; }
.hero-req li::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: #8fb0ea; flex: none; }
.hero-req strong { color: #fff; }

/* 상단 엑셀 그림 */
.hero-visual { display: flex; justify-content: center; }
.sheet {
  width: 100%; max-width: 460px;
  background: #fbfcfe; color: #1c2536; border-radius: 12px; overflow: hidden;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
  transform: perspective(1200px) rotateY(-6deg) rotateX(2deg);
}
.sheet-bar { display: flex; align-items: center; gap: 6px; padding: 10px 14px; background: #eef1f6; border-bottom: 1px solid #dde3ec; }
.dot { width: 10px; height: 10px; border-radius: 50%; background: #cfd6e2; }
.sheet-title { margin-left: 8px; font-size: 13px; color: #5a6476; font-weight: 600; }
.sheet-grid { padding: 6px 0; }
.row { display: grid; grid-template-columns: 1.3fr repeat(3, 1fr); align-items: center; gap: 12px; padding: 7px 16px; font-size: 13px; border-bottom: 1px solid #edf0f5; }
.row:last-child { border-bottom: 0; }
.row.head { font-weight: 700; color: #5a6476; font-size: 12px; background: #f5f7fb; }
.row.head span:not(:first-child) { text-align: right; }
.row i { display: block; height: 8px; border-radius: 4px; background: linear-gradient(90deg, #c9d6ee, #8ea8d6); width: var(--w); justify-self: end; }
.sheet-tabs { display: flex; gap: 2px; padding: 0 10px; background: #eef1f6; border-top: 1px solid #dde3ec; font-size: 12px; }
.sheet-tabs span { padding: 7px 10px; color: #5a6476; }
.sheet-tabs .active { background: #fbfcfe; color: var(--navy); font-weight: 700; box-shadow: inset 0 2px 0 var(--navy); }

/* 섹션 공통 */
.section { padding: 80px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: clamp(26px, 3.4vw, 34px); font-weight: 800; letter-spacing: -0.02em; margin-bottom: 12px; }
.section-lead { color: var(--muted); font-size: 17px; margin-bottom: 36px; max-width: 40em; }

/* 기능 카드 */
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; box-shadow: var(--shadow);
}
.card h3 { font-size: 18px; margin-bottom: 8px; }
.card p { color: var(--muted); font-size: 15px; }
.card strong { color: var(--text); font-weight: 600; }
.card-icon {
  width: 44px; height: 44px; border-radius: 10px; background: var(--accent-soft); color: var(--accent-text);
  display: grid; place-items: center; margin-bottom: 16px;
}
.card-icon svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.how {
  margin-top: 28px; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 28px; background: var(--bg-alt);
}
.how-title { font-size: 15px; font-weight: 700; color: var(--accent-text); margin-bottom: 14px; }
.how-list { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.how-list li { display: flex; flex-direction: column; gap: 4px; padding-left: 16px; border-left: 3px solid var(--accent); }
.how-list strong { font-size: 16px; }
.how-list span { color: var(--muted); font-size: 15px; }

/* 스크린샷 */
.shots { display: grid; grid-template-columns: 2fr 1fr; grid-template-rows: auto auto; gap: 20px; }
.shot { margin: 0; }
.shot-main { grid-row: span 2; }
.shot-frame {
  position: relative; aspect-ratio: 16 / 10; border-radius: var(--radius); overflow: hidden;
  background: var(--surface); border: 1px solid var(--border); box-shadow: var(--shadow);
}
.shot-main .shot-frame { aspect-ratio: auto; height: calc(100% - 34px); min-height: 300px; }
.shot-frame img { width: 100%; height: 100%; object-fit: cover; object-position: top left; }
.shot-placeholder { display: none; }
.shot-frame.is-empty {
  display: grid; place-items: center;
  background:
    repeating-linear-gradient(45deg, transparent 0 12px, color-mix(in srgb, var(--border) 45%, transparent) 12px 13px),
    var(--surface);
  border-style: dashed;
}
.shot-frame.is-empty .shot-placeholder { display: block; color: var(--muted); font-size: 14px; font-weight: 600; }
.shot figcaption { font-size: 14px; color: var(--muted); margin-top: 10px; }

/* 단계 */
.steps { list-style: none; padding: 0; margin: 0; counter-reset: step; }
.steps > li { position: relative; padding: 0 0 28px 56px; counter-increment: step; }
.steps > li::before {
  content: counter(step);
  position: absolute; left: 0; top: -2px;
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--accent); color: #fff; font-weight: 800; font-size: 16px;
  display: grid; place-items: center;
}
.steps > li::after {
  content: ""; position: absolute; left: 17px; top: 40px; bottom: 6px; width: 2px; background: var(--border);
}
.steps > li:last-child { padding-bottom: 0; }
.steps > li:last-child::after { display: none; }
.steps h3 { font-size: 18px; margin-bottom: 6px; }
.steps p { color: var(--muted); }

.callout {
  margin-top: 14px; padding: 14px 18px; border-radius: 10px;
  background: var(--info-bg); border: 1px solid var(--info-border); font-size: 15px;
}
.callout p { color: var(--text); }
.callout-warn { background: var(--warn-bg); border-color: var(--warn-border); margin-top: 32px; }
.callout-warn p, .callout-warn strong { color: var(--warn-text); }

/* 처음 실행 */
.first-run { display: grid; grid-template-columns: 1.2fr 1fr; gap: 56px; align-items: center; }
.first-run .section-title { margin-bottom: 32px; }
.mock-window {
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  box-shadow: var(--shadow); overflow: hidden; max-width: 420px; width: 100%; justify-self: center;
}
.mock-titlebar { padding: 10px 16px; font-size: 13px; font-weight: 700; background: var(--bg-alt); border-bottom: 1px solid var(--border); }
.mock-body { padding: 22px; display: flex; flex-direction: column; }
.mock-body label { font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.mock-body label span { color: var(--muted); font-weight: 400; font-size: 12px; margin-left: 4px; }
.mock-input {
  border: 1px solid var(--border); border-radius: 6px; padding: 8px 12px; font-size: 14px;
  color: var(--muted); margin-bottom: 16px; background: var(--bg); white-space: nowrap; overflow: hidden; text-overflow: clip;
}
.mock-input.mono { font-family: var(--mono); letter-spacing: 0.05em; }
.mock-btn {
  align-self: flex-end; background: var(--accent); color: #fff; font-size: 14px; font-weight: 700;
  padding: 8px 16px; border-radius: 6px; margin-top: 4px;
}

/* FAQ */
.faq { display: flex; flex-direction: column; gap: 12px; }
.faq details {
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px; padding: 0 20px;
}
.faq summary {
  cursor: pointer; list-style: none; font-weight: 700; font-size: 17px; padding: 18px 28px 18px 0; position: relative;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; position: absolute; right: 4px; top: 50%; width: 9px; height: 9px;
  border-right: 2px solid var(--muted); border-bottom: 2px solid var(--muted);
  transform: translateY(-70%) rotate(45deg); transition: transform 0.2s;
}
.faq details[open] summary::after { transform: translateY(-30%) rotate(-135deg); }
.faq details p { color: var(--muted); padding-bottom: 4px; }
.faq details p:last-child { padding-bottom: 18px; }

/* 후원 */
.donate { text-align: center; }
.donate .section-lead { margin-left: auto; margin-right: auto; margin-bottom: 28px; }
.donate-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.btn-donate { background: var(--surface); color: var(--text); border-color: var(--border); box-shadow: var(--shadow); min-width: 180px; }
a.btn-donate:hover { border-color: var(--accent); color: var(--accent-text); transform: translateY(-1px); }
.btn-donate.is-disabled { color: var(--muted); box-shadow: none; cursor: default; background: var(--bg-alt); font-weight: 600; }
.donate-note { margin-top: 20px; color: var(--muted); font-size: 15px; }

/* 하단 */
.site-footer { background: var(--bg-alt); border-top: 1px solid var(--border); padding: 56px 0 32px; font-size: 14px; color: var(--muted); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 32px; margin-bottom: 36px; }
.footer-brand { font-weight: 800; font-size: 18px; color: var(--text); margin-bottom: 6px; }
.footer-head { font-weight: 700; color: var(--text); margin-bottom: 8px; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 6px; }
.disclaimer { border-top: 1px solid var(--border); padding-top: 24px; font-size: 13px; line-height: 1.7; }
.copyright { margin-top: 20px; font-size: 13px; }

/* 반응형 */
@media (max-width: 1000px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .hero-inner { grid-template-columns: 1fr; gap: 48px; }
  .sheet { transform: none; }
}

@media (max-width: 860px) {
  .site-nav { display: none; }
  .header-inner { justify-content: space-between; }
  .how-list { grid-template-columns: 1fr; gap: 16px; }
  .shots { grid-template-columns: 1fr; }
  .shot-main { grid-row: auto; }
  .shot-main .shot-frame { aspect-ratio: 16 / 10; height: auto; min-height: 0; }
  .first-run { grid-template-columns: 1fr; gap: 40px; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}

@media (max-width: 560px) {
  .container { padding: 0 16px; }
  .hero { padding: 48px 0 56px; }
  .lead { font-size: 16px; }
  .btn-hero { width: 100%; }
  .section { padding: 56px 0; }
  .section-lead { font-size: 16px; margin-bottom: 28px; }
  .cards { grid-template-columns: 1fr; gap: 14px; }
  .card { padding: 20px; }
  .how { padding: 20px; }
  .steps > li { padding-left: 50px; }
  .sheet-tabs span:nth-child(n + 4) { display: none; }
  .row { gap: 8px; padding: 7px 12px; }
  .btn-donate { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn, .faq summary::after { transition: none; }
}