/* ===== base ===== */
:root {
  --bg: #fafafa;
  --bg-soft: #f0f0f1;
  --fg: #1a1a1e;
  --fg-dim: #55555c;
  --fg-faint: #9a9aa2;
  --line: #e2e2e5;
  --accent: #1f6feb;
  --accent-dim: #6e8fc7;
  --mono: "SFMono-Regular", "JetBrains Mono", "Fira Code", Consolas, "Liberation Mono", Menlo, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --maxw: 720px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--mono);
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }

::selection { background: #cfe0fb; color: #1a1a1e; }

/* ===== layout ===== */
.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
  padding: 22px 0;
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}
.brand {
  font-weight: 700;
  letter-spacing: .5px;
  color: var(--fg);
}
.brand .prompt { color: var(--accent); }
.brand:hover { text-decoration: none; }

.nav {
  display: flex;
  gap: 20px;
  font-size: 14px;
}
.nav a {
  color: var(--fg-dim);
  transition: color .15s ease;
}
.nav a:hover { color: var(--fg); text-decoration: none; }
.nav a.active { color: var(--fg); }
.nav a.active::before { content: "› "; color: var(--accent); }

main { padding: 56px 0 80px; }

footer {
  border-top: 1px solid var(--line);
  padding: 24px 0 48px;
  color: var(--fg-faint);
  font-size: 13px;
}
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

/* ===== home ===== */
.hero { margin-bottom: 64px; }
.hero .kicker {
  color: var(--accent);
  font-size: 13px;
  letter-spacing: 1px;
  margin-bottom: 14px;
}
.hero h1 {
  font-size: 30px;
  line-height: 1.3;
  margin: 0 0 18px;
  font-weight: 700;
}
.hero p { color: var(--fg-dim); max-width: 60ch; }
.hero .blink {
  display: inline-block;
  width: 9px; height: 18px;
  background: var(--accent);
  vertical-align: -2px;
  margin-left: 4px;
  animation: blink 1.1s steps(1) infinite;
}
@keyframes blink { 50% { opacity: 0; } }

.section-label {
  color: var(--fg-faint);
  font-size: 12px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  margin: 0 0 18px;
  border-bottom: 1px dashed var(--line);
  padding-bottom: 8px;
}

/* post list */
.post-list { list-style: none; margin: 0; padding: 0; }
.post-list li {
  border-bottom: 1px solid var(--line);
  padding: 16px 0;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
}
.post-list li:last-child { border-bottom: none; }
.post-list .meta { color: var(--fg-faint); font-size: 13px; white-space: nowrap; }
.post-list a { color: var(--fg); }
.post-list a:hover { color: var(--accent); text-decoration: none; }
.post-list .title { display: block; }
.post-list .desc { color: var(--fg-dim); font-size: 13px; margin-top: 4px; }

/* ===== post detail ===== */
.post-header { margin-bottom: 40px; }
.post-header .date { color: var(--fg-faint); font-size: 13px; margin-bottom: 10px; }
.post-header h1 { font-size: 26px; margin: 0 0 12px; line-height: 1.3; }
.post-header .tags { color: var(--accent-dim); font-size: 13px; }

.post-body h2 {
  font-size: 19px;
  margin: 40px 0 14px;
  padding-left: 12px;
  border-left: 3px solid var(--accent);
}
.post-body h3 { font-size: 16px; margin: 28px 0 10px; color: var(--fg); }
.post-body p { color: var(--fg-dim); }
.post-body ul, .post-body ol { color: var(--fg-dim); padding-left: 22px; }
.post-body li { margin: 6px 0; }
.post-body strong { color: var(--fg); }

pre {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 16px 18px;
  overflow-x: auto;
  font-size: 13.5px;
  line-height: 1.6;
  margin: 18px 0;
}
pre .c { color: #8a8a92; }
pre .p { color: var(--accent); }
pre .s { color: #1a7f37; }

code {
  font-family: var(--mono);
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 1px 6px;
  font-size: 13px;
}

blockquote {
  margin: 18px 0;
  padding: 4px 16px;
  border-left: 3px solid var(--line);
  color: var(--fg-faint);
}

.back-link { color: var(--fg-dim); font-size: 14px; }
.back-link:hover { color: var(--accent); }

/* ===== about ===== */
.about p { color: var(--fg-dim); }
.about .lead { color: var(--fg); font-size: 16px; }
.contact-list { list-style: none; padding: 0; margin: 24px 0 0; }
.contact-list li {
  display: flex;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}
.contact-list .k { color: var(--accent); min-width: 92px; }
.contact-list .v { color: var(--fg); }

/* ===== responsive ===== */
@media (max-width: 560px) {
  body { font-size: 14px; }
  .hero h1, .post-header h1 { font-size: 23px; }
  .post-list li { flex-direction: column; gap: 4px; }
}