/* APRL Tutorial · Common Design System (blue tone) */

:root {
  --naver-green: #0064FF;
  --naver-green-dark: #004FCC;
  --naver-green-soft: #E6F0FF;
  --naver-green-pale: #F4F8FF;
  --ink: #191919;
  --ink-soft: #333;
  --ink-muted: #6B6B6B;
  --line: #E5E5E5;
  --line-soft: #F2F2F2;
  --bg: #FFFFFF;
  --bg-soft: #FAFAFA;
  --warn-bg: #FFF8E7;
  --warn-line: #F5C518;
  --info-bg: #EEF7FF;
  --info-line: #00A3FF;
  --code-bg: #F7F7F8;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
code, pre, .mono { font-family: 'JetBrains Mono', 'D2Coding', 'Consolas', monospace; }

/* === 상단바 === */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: #fff;
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 1080px; margin: 0 auto;
  display: flex; align-items: center; gap: 24px;
  padding: 14px 24px;
}
.brand {
  font-weight: 800; font-size: 22px;
  color: var(--naver-green);
  letter-spacing: -0.5px;
  display: flex; align-items: baseline; gap: 8px;
  text-decoration: none;
}
.brand-sub { color: var(--ink); font-size: 14px; font-weight: 600; letter-spacing: 0; }
.topnav { display: flex; gap: 4px; margin-left: auto; font-size: 14px; }
.topnav a {
  color: var(--ink-soft); text-decoration: none;
  padding: 6px 12px; border-radius: 999px;
}
.topnav a:hover, .topnav a.active {
  background: var(--naver-green-soft); color: var(--naver-green-dark);
}

/* === 헤드라인 === */
.headline {
  border-bottom: 1px solid var(--line);
  background: radial-gradient(ellipse at top right, var(--naver-green-pale) 0%, transparent 60%), #fff;
}
.headline-inner {
  max-width: 1080px; margin: 0 auto;
  padding: 56px 24px 40px;
}
.kicker {
  display: inline-block;
  font-size: 12px; font-weight: 700;
  color: var(--naver-green-dark);
  background: var(--naver-green-soft);
  padding: 5px 12px; border-radius: 999px;
  margin-bottom: 18px;
  letter-spacing: 0.3px;
}
h1.title {
  font-family: 'Noto Serif KR', 'Pretendard', serif;
  font-weight: 700;
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1.3;
  margin: 0 0 16px;
  letter-spacing: -1px;
  color: var(--ink);
}
h1.title .hl {
  background: linear-gradient(transparent 60%, var(--naver-green-soft) 60%);
  padding: 0 4px;
}
.subtitle {
  font-size: 17px; color: var(--ink-muted);
  margin: 0 0 24px; max-width: 720px;
}
.meta {
  display: flex; gap: 16px; flex-wrap: wrap;
  font-size: 13px; color: var(--ink-muted);
  border-top: 1px solid var(--line-soft);
  padding-top: 16px;
}
.meta .author { color: var(--ink); font-weight: 600; }
.meta .dot { color: var(--line); }

/* === 본문 레이아웃 === */
.layout {
  max-width: 1080px; margin: 0 auto;
  padding: 32px 24px 80px;
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 56px;
}
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; gap: 0; }
  aside.toc { display: none; }
}
main { min-width: 0; max-width: 760px; }

/* === 사이드 목차 === */
aside.toc {
  position: sticky; top: 80px;
  align-self: start;
  font-size: 13px;
  border-left: 2px solid var(--line);
  padding: 4px 0 4px 16px;
}
aside.toc .toc-label {
  font-size: 11px; font-weight: 700; letter-spacing: 1px;
  color: var(--naver-green-dark);
  margin-bottom: 12px;
}
aside.toc ol {
  list-style: none; padding: 0; margin: 0;
  counter-reset: toc;
}
aside.toc li {
  counter-increment: toc;
  margin-bottom: 8px;
}
aside.toc li::before {
  content: counter(toc, decimal-leading-zero);
  color: var(--naver-green);
  font-weight: 700;
  margin-right: 8px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
}
aside.toc a {
  color: var(--ink-soft); text-decoration: none;
}
aside.toc a:hover { color: var(--naver-green-dark); }

/* === 제목 === */
h2.section, .markdown-body h2 {
  font-family: 'Pretendard', sans-serif;
  font-size: 24px; font-weight: 700;
  margin: 56px 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--ink);
  letter-spacing: -0.5px;
  display: flex; align-items: baseline; gap: 12px;
}
h2.section .num {
  font-family: 'JetBrains Mono', monospace;
  color: var(--naver-green);
  font-size: 16px;
  font-weight: 600;
}
h3.sub, .markdown-body h3 {
  font-size: 18px; font-weight: 700;
  margin: 32px 0 12px;
  color: var(--ink);
  padding-left: 12px;
  border-left: 4px solid var(--naver-green);
}
h4.mini, .markdown-body h4 {
  font-size: 15px; font-weight: 700;
  margin: 20px 0 8px;
  color: var(--ink-soft);
}

p, .markdown-body p { margin: 12px 0; color: var(--ink-soft); }
p.lead {
  font-size: 17px;
  color: var(--ink);
  border-left: 3px solid var(--naver-green);
  padding: 14px 18px;
  background: var(--naver-green-pale);
  margin: 16px 0 24px;
}
strong { color: var(--ink); font-weight: 700; }
em { font-style: normal; background: linear-gradient(transparent 65%, #FFF1A8 65%); padding: 0 2px; }

/* === 코드 === */
code {
  background: var(--code-bg);
  padding: 2px 7px;
  border-radius: 4px;
  font-size: 0.88em;
  color: #C53030;
  border: 1px solid var(--line-soft);
}
pre {
  background: #1E1E1E;
  color: #E8E8E8;
  padding: 18px 20px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.65;
  margin: 16px 0;
  border: 1px solid #333;
}
pre code {
  background: transparent; color: inherit;
  padding: 0; border: none; font-size: inherit;
}

/* === 박스 === */
.box {
  border-radius: 8px;
  padding: 16px 20px;
  margin: 20px 0;
  font-size: 15px;
  line-height: 1.7;
}
.box .box-title {
  font-weight: 700;
  margin-bottom: 6px;
  display: flex; align-items: center; gap: 8px;
  font-size: 14px;
}
.box .box-title .tag {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 700;
  letter-spacing: 0.3px;
}
.box.info { background: var(--info-bg); border-left: 4px solid var(--info-line); }
.box.info .tag { background: var(--info-line); color: #fff; }
.box.warn { background: var(--warn-bg); border-left: 4px solid var(--warn-line); }
.box.warn .tag { background: var(--warn-line); color: #000; }
.box.tip  { background: var(--naver-green-soft); border-left: 4px solid var(--naver-green); }
.box.tip .tag { background: var(--naver-green); color: #fff; }

/* === 표 === */
table, .markdown-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 14px;
}
th, td, .markdown-body th, .markdown-body td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}
th, .markdown-body th {
  background: var(--bg-soft);
  font-weight: 700;
  font-size: 13px;
  color: var(--ink);
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}
tbody tr:hover { background: var(--naver-green-pale); }

/* === 리스트 === */
ul.clean, ol.clean, .markdown-body ul, .markdown-body ol { padding-left: 22px; }
ul.clean li, ol.clean li, .markdown-body li { margin: 6px 0; color: var(--ink-soft); }

/* === kbd === */
kbd {
  display: inline-block;
  padding: 2px 7px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  background: #fff;
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 4px;
  color: var(--ink);
}

/* === 푸터 === */
footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  padding: 32px 24px;
  font-size: 13px;
  color: var(--ink-muted);
}
footer .footer-inner {
  max-width: 1080px; margin: 0 auto;
  display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap;
}

/* === 마크다운 페이지 전용 보강 === */
.markdown-body {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}
.markdown-body h1 {
  font-family: 'Noto Serif KR', serif;
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -1px;
  margin: 8px 0 24px;
  padding-bottom: 16px;
  border-bottom: 3px solid var(--ink);
}
.markdown-body hr {
  border: none;
  border-top: 1px solid var(--line);
  margin: 32px 0;
}
.markdown-body blockquote {
  margin: 16px 0;
  padding: 12px 18px;
  background: var(--naver-green-pale);
  border-left: 4px solid var(--naver-green);
  color: var(--ink-soft);
}
.markdown-body blockquote p { margin: 4px 0; }

/* === 파일 다운로드 카드 === */
.dl-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
  margin: 20px 0;
}
.dl-card {
  display: block;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  text-decoration: none;
  color: var(--ink);
  background: #fff;
  transition: all 0.15s;
}
.dl-card:hover {
  border-color: var(--naver-green);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0,100,255,0.08);
}
.dl-card .dl-name {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 700;
  color: var(--naver-green-dark);
  margin-bottom: 4px;
}
.dl-card .dl-desc {
  font-size: 12px;
  color: var(--ink-muted);
  line-height: 1.4;
}