:root {
  --font-sans: "Noto Sans SC", system-ui, -apple-system, Segoe UI, Roboto, Arial, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;

  --bg: #0a0b10;
  --bg-elev: rgba(255, 255, 255, 0.06);
  --bg-elev-2: rgba(255, 255, 255, 0.09);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.72);
  --faint: rgba(255, 255, 255, 0.55);
  --border: rgba(255, 255, 255, 0.12);
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.42);

  --primary: #7c3aed;
  --primary-2: #22d3ee;
  --accent: linear-gradient(135deg, var(--primary), var(--primary-2));

  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 12px;
  --container: 1120px;
}

:root[data-theme="light"] {
  --bg: #f7f7fb;
  --bg-elev: rgba(12, 14, 22, 0.045);
  --bg-elev-2: rgba(12, 14, 22, 0.07);
  --text: rgba(12, 14, 22, 0.92);
  --muted: rgba(12, 14, 22, 0.72);
  --faint: rgba(12, 14, 22, 0.58);
  --border: rgba(12, 14, 22, 0.1);
  --shadow: 0 18px 50px rgba(12, 14, 22, 0.14);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 15% 10%, rgba(124, 58, 237, 0.28), transparent 55%),
    radial-gradient(900px 500px at 85% 20%, rgba(34, 211, 238, 0.22), transparent 55%),
    radial-gradient(900px 700px at 60% 95%, rgba(124, 58, 237, 0.18), transparent 55%),
    var(--bg);
  line-height: 1.6;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select {
  font: inherit;
}

.container {
  width: min(var(--container), calc(100% - 48px));
  margin: 0 auto;
}

.skip-link {
  position: absolute;
  top: 10px;
  left: 10px;
  padding: 10px 12px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 999px;
  transform: translateY(-140%);
  transition: transform 160ms ease;
  z-index: 999;
}
.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--bg) 75%, transparent);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 140px;
}

.brand-mark {
  width: 30px;
  height: 30px;
  border-radius: 10px;
  background: var(--accent);
  box-shadow: 0 14px 30px rgba(124, 58, 237, 0.28);
}

.brand-text {
  font-weight: 700;
  letter-spacing: 0.2px;
}

.brand-sub {
  margin-left: 6px;
  color: var(--faint);
  font-weight: 600;
  font-size: 12px;
  padding: 2px 8px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-elev);
}

.nav {
  display: flex;
  gap: 6px;
  align-items: center;
}

.nav-link {
  padding: 10px 12px;
  border-radius: 999px;
  color: var(--muted);
  border: 1px solid transparent;
  transition: background 160ms ease, border-color 160ms ease, color 160ms ease;
}
.nav-link:hover {
  background: var(--bg-elev);
  border-color: var(--border);
  color: var(--text);
}
.nav-link.is-active {
  background: var(--bg-elev-2);
  border-color: var(--border);
  color: var(--text);
}

.header-actions {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.icon-btn {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--bg-elev);
  box-shadow: none;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: transform 160ms ease, background 160ms ease;
}
.icon-btn:hover {
  background: var(--bg-elev-2);
  transform: translateY(-1px);
}
.icon-btn:active {
  transform: translateY(0);
}

.icon {
  width: 18px;
  height: 18px;
  display: inline-block;
  position: relative;
}

.icon[data-icon="theme"]::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 999px;
  background: conic-gradient(from 180deg, rgba(255, 255, 255, 0.92), rgba(255, 255, 255, 0.25));
  mask: radial-gradient(circle at 35% 35%, transparent 40%, #000 41%);
}

:root[data-theme="light"] .icon[data-icon="theme"]::before {
  background: conic-gradient(from 180deg, rgba(12, 14, 22, 0.92), rgba(12, 14, 22, 0.25));
}

.icon[data-icon="menu"]::before,
.icon[data-icon="menu"]::after {
  content: "";
  position: absolute;
  left: 2px;
  right: 2px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
  opacity: 0.9;
}
.icon[data-icon="menu"]::before {
  top: 5px;
  box-shadow: 0 5px 0 0 currentColor, 0 10px 0 0 currentColor;
}
.icon[data-icon="search"]::before {
  content: "";
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 999px;
  border: 2px solid currentColor;
  left: 0;
  top: 0;
  opacity: 0.75;
}
.icon[data-icon="search"]::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
  right: 0;
  bottom: 1px;
  transform: rotate(45deg);
  transform-origin: right center;
  opacity: 0.75;
}

.nav-toggle {
  display: none;
}

.hero {
  padding: 56px 0 10px;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 28px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--muted);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 12px;
  margin: 0 0 14px;
}
.eyebrow::before {
  content: "";
  width: 30px;
  height: 1px;
  background: color-mix(in srgb, var(--text) 22%, transparent);
}

.hero-title {
  margin: 0 0 14px;
  font-size: clamp(34px, 3.6vw, 52px);
  line-height: 1.12;
  letter-spacing: -0.02em;
}

.gradient-text {
  background: var(--accent);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-desc {
  margin: 0 0 22px;
  color: var(--muted);
  font-size: 16px;
  max-width: 56ch;
}

.hero-cta {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

.btn {
  border-radius: 999px;
  padding: 10px 16px;
  border: 1px solid var(--border);
  background: var(--bg-elev);
  color: var(--text);
  font-weight: 650;
  cursor: pointer;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
}
.btn:hover {
  background: var(--bg-elev-2);
  transform: translateY(-1px);
}
.btn:active {
  transform: translateY(0);
}

.btn-primary {
  border-color: color-mix(in srgb, var(--primary) 40%, var(--border));
  background: color-mix(in srgb, var(--primary) 26%, var(--bg-elev));
  box-shadow: 0 18px 40px rgba(124, 58, 237, 0.18);
}
.btn-primary:hover {
  background: color-mix(in srgb, var(--primary) 32%, var(--bg-elev-2));
}

.btn-ghost {
  background: transparent;
}

.hero-stats {
  display: flex;
  gap: 10px;
  margin-top: 18px;
  flex-wrap: wrap;
}
.stat {
  flex: 0 0 auto;
  min-width: 120px;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  background: var(--bg-elev);
  border: 1px solid var(--border);
}
.stat-value {
  font-size: 18px;
  font-weight: 750;
  letter-spacing: -0.02em;
}
.stat-label {
  font-size: 12px;
  color: var(--muted);
  margin-top: 2px;
}

.hero-card {
  position: relative;
  min-height: 340px;
}

.glass {
  position: relative;
  height: 340px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
  box-shadow: var(--shadow);
  overflow: hidden;
}
:root[data-theme="light"] .glass {
  background: linear-gradient(180deg, rgba(12, 14, 22, 0.05), rgba(12, 14, 22, 0.025));
}

.glass-top {
  height: 42px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 14px;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 30%, transparent);
}
.dot {
  width: 10px;
  height: 10px;
  border-radius: 999px;
  opacity: 0.95;
}
.dot-red {
  background: #ef4444;
}
.dot-yellow {
  background: #f59e0b;
}
.dot-green {
  background: #22c55e;
}

.glass-body {
  padding: 18px 18px 22px;
}
.code-line {
  height: 10px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--text) 16%, transparent);
  margin: 14px 0;
}
.w-50 {
  width: 50%;
}
.w-60 {
  width: 60%;
}
.w-70 {
  width: 70%;
}
.w-80 {
  width: 80%;
}
.w-90 {
  width: 90%;
}

.ambient {
  position: absolute;
  inset: auto;
  width: 220px;
  height: 220px;
  border-radius: 999px;
  filter: blur(32px);
  opacity: 0.55;
  pointer-events: none;
}
.ambient-a {
  right: -40px;
  top: 30px;
  background: rgba(124, 58, 237, 0.65);
}
.ambient-b {
  left: -50px;
  bottom: -40px;
  background: rgba(34, 211, 238, 0.55);
}

.section {
  padding: 46px 0;
}
.section.subtle {
  padding-top: 26px;
}

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.section-title {
  margin: 0;
  font-size: 22px;
  letter-spacing: -0.01em;
}

.section-tools {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
}

.search {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-elev);
}
.search input {
  border: none;
  outline: none;
  background: transparent;
  color: var(--text);
  width: 220px;
}
.search input::placeholder {
  color: var(--faint);
}

.select {
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-elev);
  color: var(--text);
  padding: 10px 12px;
  outline: none;
  cursor: pointer;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 14px;
}

.post-card {
  grid-column: span 4;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-elev);
  box-shadow: none;
  overflow: hidden;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease;
}
.post-card:hover {
  transform: translateY(-4px);
  background: var(--bg-elev-2);
  border-color: color-mix(in srgb, var(--primary) 20%, var(--border));
}

.post-cover {
  height: 140px;
  background:
    radial-gradient(800px 220px at 20% 30%, rgba(124, 58, 237, 0.38), transparent 55%),
    radial-gradient(800px 220px at 80% 60%, rgba(34, 211, 238, 0.3), transparent 55%),
    color-mix(in srgb, var(--bg) 80%, transparent);
  border-bottom: 1px solid var(--border);
}

.post-body {
  padding: 16px 16px 18px;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 12px;
}

.pill {
  padding: 3px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 25%, transparent);
}

.post-title {
  margin: 10px 0 8px;
  font-size: 18px;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.post-excerpt {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.callout {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: linear-gradient(
    135deg,
    color-mix(in srgb, var(--primary) 20%, var(--bg-elev)) 0%,
    color-mix(in srgb, var(--primary-2) 14%, var(--bg-elev)) 100%
  );
  box-shadow: var(--shadow);
  padding: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.callout-title {
  margin: 0;
  font-size: 20px;
  letter-spacing: -0.01em;
}
.callout-desc {
  margin: 6px 0 0;
  color: var(--muted);
}

.subscribe {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
}
.input {
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  padding: 10px 12px;
  min-width: min(340px, 78vw);
  outline: none;
}
:root[data-theme="light"] .input {
  background: rgba(12, 14, 22, 0.04);
}
.input::placeholder {
  color: var(--faint);
}

.site-footer {
  padding: 26px 0 40px;
  border-top: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 84%, transparent);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.brand-mini {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 750;
}

.muted {
  color: var(--muted);
  margin: 10px 0 0;
}

.footer-right {
  display: inline-flex;
  gap: 10px;
  flex-wrap: wrap;
}
.footer-link {
  padding: 8px 10px;
  border-radius: 999px;
  border: 1px solid transparent;
  color: var(--muted);
}
.footer-link:hover {
  border-color: var(--border);
  background: var(--bg-elev);
  color: var(--text);
}

/* content pages */
.page {
  padding: 46px 0 30px;
}
.page-title {
  margin: 0;
  font-size: 34px;
  letter-spacing: -0.02em;
  line-height: 1.15;
}
.page-desc {
  margin: 10px 0 0;
  color: var(--muted);
  max-width: 70ch;
}

.prose {
  margin-top: 22px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-elev);
  padding: 22px;
  box-shadow: var(--shadow);
}
.prose h2 {
  margin: 22px 0 10px;
  font-size: 20px;
  letter-spacing: -0.01em;
}
.prose p {
  margin: 10px 0;
  color: var(--muted);
}
.prose a {
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--primary) 45%, transparent);
  text-underline-offset: 3px;
}
.prose code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.92em;
  padding: 2px 6px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 35%, transparent);
  color: color-mix(in srgb, var(--text) 92%, var(--primary));
}
.prose pre {
  overflow: auto;
  padding: 14px;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 70%, transparent);
}
.prose pre code {
  border: none;
  background: transparent;
  padding: 0;
}

/* mobile nav */
@media (max-width: 860px) {
  .hero-inner {
    grid-template-columns: 1fr;
  }
  .hero-card {
    min-height: 300px;
  }
  .nav-toggle {
    display: grid;
  }
  .nav {
    position: absolute;
    top: 72px;
    left: 50%;
    transform: translateX(-50%);
    width: min(var(--container), calc(100% - 48px));
    padding: 10px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    background: color-mix(in srgb, var(--bg) 80%, transparent);
    box-shadow: var(--shadow);
    display: none;
  }
  .nav.is-open {
    display: flex;
  }
  .nav-link {
    flex: 1 1 auto;
    text-align: center;
  }
}

@media (max-width: 980px) {
  .post-card {
    grid-column: span 6;
  }
}
@media (max-width: 620px) {
  .post-card {
    grid-column: span 12;
  }
  .search input {
    width: 180px;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
    animation: none !important;
  }
}