:root {
  --bg: #eef2f1;
  --ink: #12141a;
  --muted: #5d6670;
  --line: #d7dde0;
  --accent: #10b981;
  --accent-soft: rgba(16, 185, 129, 0.10);
  --panel: rgba(255, 255, 255, 0.78);
  --code-bg: #f4f6f7;
  --max: 1120px;
}

html[data-theme="dark"] {
  --bg: #0b1114;
  --ink: #eef4f5;
  --muted: #a8b7be;
  --line: #25323a;
  --accent: #21d8a0;
  --accent-soft: rgba(33, 216, 160, 0.10);
  --panel: rgba(16, 23, 28, 0.78);
  --code-bg: #151e24;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0b1114;
    --ink: #eef4f5;
    --muted: #a8b7be;
    --line: #25323a;
    --accent: #21d8a0;
    --accent-soft: rgba(33, 216, 160, 0.10);
    --panel: rgba(16, 23, 28, 0.78);
    --code-bg: #151e24;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Manrope", "Avenir Next", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% -10%, rgba(63, 110, 220, 0.16) 0, transparent 42%),
    radial-gradient(circle at 100% 0%, rgba(22, 148, 118, 0.16) 0, transparent 35%),
    var(--bg);
  line-height: 1.55;
}

html { scroll-behavior: smooth; color-scheme: light dark; }

.wrap { width: min(var(--max), 92vw); margin: 0 auto; }

/* --- Header (shared with other pages) --- */
.announcement {
  margin-top: 10px;
  border: 1px solid color-mix(in oklab, var(--line) 85%, white);
  border-radius: 999px;
  padding: 8px 14px;
  text-align: center;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  color: var(--ink);
  background: color-mix(in oklab, var(--panel) 90%, white);
}

header { position: sticky; top: 10px; z-index: 10; }

.nav {
  margin-top: 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--panel);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.25), 0 14px 40px rgba(0,0,0,.16);
  backdrop-filter: blur(18px) saturate(145%);
}

.logo { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.logo-icon { width: 30px; height: 30px; border-radius: 8px; }
.logo-word { font-size: 1.35rem; font-weight: 820; color: var(--ink); }
.logo-word span { color: var(--accent); }
.top-links { display: flex; align-items: center; gap: 8px; }
.top-link {
  text-decoration: none;
  color: var(--ink);
  border: 1px solid var(--line);
  background: color-mix(in oklab, var(--panel) 70%, white 30%);
  border-radius: 999px;
  padding: 8px 12px;
  font-size: .84rem;
  font-weight: 700;
}
.top-link.active {
  color: #bdf3e3;
  background: linear-gradient(150deg, rgba(44,79,90,.82), rgba(21,58,65,.7));
  border-color: rgba(94,224,184,.34);
}
.theme-toggle {
  width: 40px; height: 40px; border-radius: 999px; cursor: pointer;
  border: 1px solid var(--line);
  background: color-mix(in oklab, var(--panel) 75%, white 25%);
  color: var(--ink);
  display: inline-flex; align-items: center; justify-content: center;
}
.theme-toggle svg { width: 18px; height: 18px; stroke: currentColor; fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.is-hidden { display: none; }

/* --- Hero image --- */
.hero-image {
  width: 100%;
  max-height: 380px;
  object-fit: cover;
  border-radius: 16px;
  margin-top: 32px;
  border: 1px solid var(--line);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.12);
}

/* --- Article layout --- */
.article-hero {
  padding: 56px 0 0;
}

.article-hero h1 {
  margin: 0;
  font-size: clamp(2rem, 4.2vw, 3.2rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  max-width: 22ch;
  text-wrap: balance;
}

.article-meta {
  margin-top: 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  color: var(--muted);
  font-size: 0.86rem;
}

.breadcrumb {
  margin-bottom: 16px;
  font-size: 0.84rem;
  color: var(--muted);
}

.breadcrumb a {
  color: var(--accent);
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.breadcrumb .sep {
  margin: 0 6px;
  opacity: 0.5;
}

/* --- Prose --- */
.prose {
  max-width: 72ch;
  padding: 32px 0 72px;
  font-size: 1.02rem;
  line-height: 1.7;
}

.prose h2 {
  margin: 42px 0 14px;
  font-size: 1.55rem;
  letter-spacing: -0.01em;
}

.prose h3 {
  margin: 32px 0 10px;
  font-size: 1.2rem;
}

.prose p {
  margin: 0 0 16px;
  color: var(--ink);
}

.prose ul,
.prose ol {
  margin: 0 0 18px;
  padding-left: 24px;
}

.prose li {
  margin-bottom: 8px;
}

.prose strong {
  font-weight: 700;
}

.prose a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.prose blockquote {
  margin: 20px 0;
  padding: 14px 18px;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 10px 10px 0;
  color: var(--ink);
  font-style: italic;
}

.prose blockquote p {
  margin: 0;
}

.prose pre {
  margin: 18px 0;
  padding: 16px 18px;
  background: var(--code-bg);
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.55;
}

.prose code {
  font-family: "SF Mono", "Fira Code", "Consolas", monospace;
  font-size: 0.88em;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 5px;
}

.prose pre code {
  background: none;
  padding: 0;
  border-radius: 0;
}

.prose table {
  width: 100%;
  margin: 18px 0;
  border-collapse: collapse;
  font-size: 0.93rem;
}

.prose th,
.prose td {
  text-align: left;
  padding: 10px 14px;
  border-bottom: 1px solid var(--line);
}

.prose th {
  font-weight: 700;
  font-size: 0.84rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--muted);
}

.callout {
  margin: 22px 0;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
}

.callout-title {
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 6px;
  color: var(--accent);
}

.callout p {
  margin: 0;
  font-size: 0.93rem;
}

/* --- Back link --- */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 8px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
}

.back-link:hover { text-decoration: underline; }

/* --- Footer --- */
footer {
  border-top: 1px solid var(--line);
  padding: 20px 0 36px;
  color: var(--muted);
  font-size: .84rem;
}

@media (max-width: 920px) {
  .nav { flex-wrap: wrap; justify-content: center; }
  .article-hero h1 { font-size: 1.8rem; }
  .prose { font-size: 0.96rem; }
}