:root {
  --paper: #f6f4ef;
  --card: #ffffff;
  --ink: #15181d;
  --ink-2: #4a505a;
  --line: #e2ded5;
  --accent: #e4572e;
  --accent-ink: #b8401d;
  --green: #3fa86a;
  --radius: 14px;
  --max: 960px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #14171c;
    --card: #1c2027;
    --ink: #eceae4;
    --ink-2: #a9aeb7;
    --line: #2c313a;
    --accent: #f06a42;
    --accent-ink: #ff8a66;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Pretendard", -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo",
    "Malgun Gothic", "Noto Sans KR", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  word-break: keep-all;
  overflow-wrap: anywhere;
}
a { color: var(--accent-ink); }
a:hover { text-decoration-thickness: 2px; }
img { max-width: 100%; display: block; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 16px; }

/* header */
.site-head {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; height: 56px; gap: 12px; }
.logo { display: flex; align-items: center; gap: 8px; font-weight: 800; letter-spacing: -0.02em; color: var(--ink); text-decoration: none; font-size: 18px; }
.logo-mark { width: 26px; height: 26px; border-radius: 7px; background: var(--ink); position: relative; flex: none; }
.logo-mark::after { content: ""; position: absolute; left: 7px; top: 6px; border-left: 12px solid var(--accent); border-top: 7px solid transparent; border-bottom: 7px solid transparent; }
.nav { display: flex; gap: 4px; }
.nav a { color: var(--ink-2); text-decoration: none; font-size: 15px; padding: 6px 10px; border-radius: 8px; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); background: var(--line); }

/* hero */
.hero { padding: 56px 0 32px; }
.eyebrow { display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 0.08em; color: var(--accent-ink); text-transform: uppercase; margin-bottom: 10px; }
.hero h1 { font-size: clamp(30px, 6vw, 48px); line-height: 1.2; letter-spacing: -0.03em; margin: 0 0 16px; }
.hero p { font-size: 18px; color: var(--ink-2); max-width: 640px; margin: 0; }

/* sections */
section { padding: 32px 0; }
h2 { font-size: clamp(22px, 4vw, 28px); letter-spacing: -0.02em; line-height: 1.3; margin: 0 0 16px; }
h3 { font-size: 19px; margin: 28px 0 8px; letter-spacing: -0.01em; }
p { margin: 0 0 14px; }
.lead { color: var(--ink-2); }

/* project card */
.projects { display: grid; gap: 16px; }
.project {
  display: grid; grid-template-columns: 1fr; gap: 0;
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
}
.project-art {
  background: #14171c; min-height: 160px; position: relative; overflow: hidden;
}
.project-art svg { width: 100%; height: 100%; display: block; }
.project-body { padding: 20px; }
.project-body h3 { margin: 0 0 6px; font-size: 22px; }
.tags { display: flex; flex-wrap: wrap; gap: 6px; margin: 0 0 12px; padding: 0; list-style: none; }
.tags li { font-size: 13px; padding: 2px 10px; border-radius: 999px; background: var(--paper); border: 1px solid var(--line); color: var(--ink-2); }
.btn {
  display: inline-flex; align-items: center; gap: 6px; min-height: 44px;
  padding: 10px 18px; border-radius: 10px; font-weight: 700; text-decoration: none;
  background: var(--accent); color: #fff; border: 0;
}
.btn:hover { background: var(--accent-ink); color: #fff; }
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.btn.ghost:hover { background: var(--line); }
.btn-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.project-body .summary { margin: 0 0 12px; padding-left: 1.2em; color: var(--ink-2); font-size: 15px; }
.project-body .summary li { margin-bottom: 4px; }
@media (min-width: 720px) {
  .project { grid-template-columns: 300px 1fr; }
  .project-art { min-height: 100%; }
}

/* article / guide */
.guide { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 20px; }
@media (min-width: 720px) { .guide { padding: 36px 40px; } }
.guide ul, .guide ol { padding-left: 1.3em; margin: 0 0 14px; }
.guide li { margin-bottom: 6px; }
.steps { counter-reset: s; list-style: none; padding: 0 !important; }
.steps li { counter-increment: s; position: relative; padding-left: 40px; margin-bottom: 12px; }
.steps li::before {
  content: counter(s); position: absolute; left: 0; top: 2px;
  width: 28px; height: 28px; border-radius: 50%; background: var(--ink); color: var(--paper);
  font-weight: 800; font-size: 14px; display: grid; place-items: center; line-height: 1;
}

/* rank ladder */
.ladder { list-style: none; padding: 0 !important; margin: 12px 0 8px; display: grid; gap: 6px; }
.ladder li { display: grid; grid-template-columns: 44px 1fr 64px; align-items: center; gap: 10px; margin: 0; font-size: 14px; }
.ladder .rk { font-weight: 700; }
.ladder .bar { height: 12px; border-radius: 6px; background: var(--line); overflow: hidden; }
.ladder .bar i { display: block; height: 100%; border-radius: 6px; background: var(--c, var(--accent)); }
.ladder .x { text-align: right; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.note { font-size: 14px; color: var(--ink-2); }

.merge-demo { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin: 12px 0 16px; font-weight: 700; }
.chip { padding: 4px 12px; border-radius: 8px; color: #fff; font-size: 14px; }

/* faq */
details { border-bottom: 1px solid var(--line); padding: 14px 0; }
details summary { cursor: pointer; font-weight: 700; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; color: var(--ink-2); font-weight: 400; }
details[open] summary::after { content: "−"; }
details p { margin: 10px 0 0; color: var(--ink-2); }

/* doc pages */
.doc { padding: 40px 0 24px; }
.doc h1 { font-size: clamp(28px, 5vw, 38px); letter-spacing: -0.03em; line-height: 1.25; margin: 0 0 16px; }

/* footer */
.site-foot { border-top: 1px solid var(--line); margin-top: 32px; padding: 24px 0 40px; font-size: 14px; color: var(--ink-2); }
.site-foot .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
.site-foot nav { display: flex; gap: 16px; flex-wrap: wrap; }
.site-foot a { color: var(--ink-2); }