:root {
  --bg: #ffffff;
  --bg-soft: #f8f7f5;
  --ink: #0d0d0d;
  --ink-2: #1a1a1a;
  --muted: #6b6b6b;
  --line: #ececec;
  --accent: #ff6b47;
  --accent-2: #ff8a5c;
  --accent-deep: #e85a3a;
  --gradient: linear-gradient(135deg, #ff6b47 0%, #ff8a5c 100%);
  --shadow-card: 0 2px 12px rgba(0,0,0,0.04), 0 8px 32px rgba(0,0,0,0.06);
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  font-weight: 400;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
nav {
  position: sticky; top: 0;
  padding: 1.1rem 2.5rem;
  display: flex; justify-content: space-between; align-items: center;
  z-index: 50;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--line);
}
.logo {
  font-weight: 800;
  font-size: 1.3rem;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--ink);
}
.logo .dot { color: var(--accent); }
.nav-back {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-size: 0.9rem;
  color: var(--muted);
  text-decoration: none;
  font-weight: 500;
}
.nav-back:hover { color: var(--ink); }

.doc-wrap {
  max-width: 760px;
  margin: 0 auto;
  padding: 4rem 2.5rem 8rem;
}
.doc-pill {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  background: rgba(255, 107, 71, 0.08);
  color: var(--accent-deep);
  border-radius: 100px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  margin-bottom: 1.5rem;
  text-transform: uppercase;
}
h1 {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  line-height: 1.05;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 1.2rem;
  color: var(--ink);
}
h1 .accent {
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 2px 8px rgba(255, 107, 71, 0.25));
}
.doc-meta {
  font-size: 0.88rem;
  color: var(--muted);
  padding-bottom: 2rem;
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--line);
  display: flex; gap: 1.8rem; flex-wrap: wrap;
}
.doc-meta strong { color: var(--ink); font-weight: 600; }
.intro {
  font-size: 1.15rem;
  line-height: 1.55;
  font-weight: 500;
  color: var(--ink-2);
  background: var(--bg-soft);
  padding: 1.5rem 1.8rem;
  border-radius: 20px;
  margin-bottom: 3rem;
  border-left: 3px solid var(--accent);
}
h2 {
  font-size: 1.55rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-top: 3rem;
  margin-bottom: 1.2rem;
  display: flex; align-items: baseline; gap: 0.8rem;
  color: var(--ink);
}
h2 .num {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.1em;
  background: rgba(255, 107, 71, 0.1);
  padding: 0.3rem 0.6rem;
  border-radius: 8px;
}
h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: 1.8rem;
  margin-bottom: 0.7rem;
  color: var(--ink);
}
p { margin-bottom: 1.1rem; color: var(--ink-2); }
ul, ol {
  margin: 0 0 1.3rem 1.3rem;
  color: var(--ink-2);
}
li { margin-bottom: 0.5rem; }
strong { font-weight: 600; color: var(--ink); }
a { color: var(--accent-deep); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; font-weight: 500; }
a:hover { color: var(--ink); }
.callout {
  background: var(--bg-soft);
  padding: 1.4rem 1.6rem;
  border-radius: 16px;
  margin: 1.8rem 0;
  font-size: 0.95rem;
  border: 1px solid var(--line);
}
.callout strong {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
}
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.3rem 0 1.8rem;
  font-size: 0.92rem;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 0 0 1px var(--line);
}
th, td {
  text-align: left;
  padding: 0.9rem 1rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
tr:last-child td { border-bottom: none; }
th {
  background: var(--bg-soft);
  font-weight: 700;
  font-size: 0.82rem;
  color: var(--ink);
  letter-spacing: 0.02em;
}
.toc {
  background: var(--bg-soft);
  padding: 1.6rem 1.8rem;
  border-radius: 20px;
  margin-bottom: 2.5rem;
}
.toc-title {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--muted);
  font-weight: 700;
  margin-bottom: 1rem;
}
.toc ol { list-style: none; margin: 0; counter-reset: toc-counter; }
.toc li { counter-increment: toc-counter; margin-bottom: 0.5rem; padding-left: 2.2rem; position: relative; font-size: 0.93rem; }
.toc li::before {
  content: counter(toc-counter, decimal-leading-zero);
  position: absolute; left: 0;
  font-weight: 700;
  color: var(--accent);
  font-size: 0.8rem;
}
.toc a { color: var(--ink-2); text-decoration: none; font-weight: 500; }
.toc a:hover { color: var(--accent); }

footer.doc-footer {
  background: var(--ink);
  color: rgba(255,255,255,0.5);
  padding: 3rem 2.5rem;
  text-align: center;
  font-size: 0.88rem;
}
footer.doc-footer a {
  color: rgba(255,255,255,0.7);
  margin: 0 0.5rem;
}
footer.doc-footer a:hover { color: var(--accent); }

@media (max-width: 700px) {
  nav { padding: 1rem 1.5rem; }
  .doc-wrap { padding: 2.5rem 1.5rem 4rem; }
  h2 { font-size: 1.3rem; flex-direction: column; gap: 0.3rem; align-items: flex-start; }
  .intro { font-size: 1rem; padding: 1.2rem; }
  .doc-meta { flex-direction: column; gap: 0.4rem; }
  footer.doc-footer { padding: 2rem 1.5rem; }
  table { font-size: 0.85rem; }
  th, td { padding: 0.7rem 0.8rem; }
}