:root {
  --bg: #07111c;
  --panel: rgba(17, 31, 47, 0.96);
  --panel-2: rgba(10, 22, 36, 0.96);
  --text: #e8eef7;
  --muted: #9eb2c8;
  --line: #29435b;
  --accent: #38bdf8;
  --accent-2: #f59e0b;
  --good: #34d399;
  --warn: #fbbf24;
  --danger: #f87171;
  --shadow: 0 12px 32px rgba(0, 0, 0, 0.28);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(56, 189, 248, 0.12), transparent 30%),
    radial-gradient(circle at top left, rgba(217, 70, 239, 0.08), transparent 25%),
    linear-gradient(180deg, #07111c 0%, #0a1624 100%);
}

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

a:hover { text-decoration: underline; }

code, pre, .mono {
  font-family: Consolas, "Courier New", monospace;
}

code {
  background: #08111b;
  color: #fde68a;
  border: 1px solid #203245;
  border-radius: 6px;
  padding: 2px 6px;
}

pre {
  background: #08111b;
  color: #dbeafe;
  border: 1px solid #203245;
  border-radius: 12px;
  padding: 14px;
  overflow: auto;
  white-space: pre-wrap;
}

.shell {
  color: #c7f9cc;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(12px);
  background: rgba(7, 17, 28, 0.92);
  border-bottom: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 14px 20px;
  display: grid;
  grid-template-columns: 280px 1fr 320px;
  gap: 14px;
  align-items: center;
}

.brand {
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand small {
  display: block;
  color: var(--muted);
  font-weight: 400;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.nav a {
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid transparent;
  color: var(--text);
}

.nav a.active,
.nav a:hover {
  background: rgba(56, 189, 248, 0.14);
  border-color: #275673;
  text-decoration: none;
}

.search-form {
  display: flex;
  gap: 8px;
}

.search-form input {
  min-width: 0;
  flex: 1;
  padding: 10px 12px;
  border-radius: 10px;
  border: 1px solid #27435f;
  background: #0b1725;
  color: var(--text);
}

.search-form button,
.button {
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid #275673;
  background: #0e2235;
  color: var(--text);
  cursor: pointer;
}

.search-form button:hover,
.button:hover {
  background: #15314d;
}

.layout {
  max-width: 1400px;
  margin: 0 auto;
  padding: 24px 20px 56px;
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 20px;
}

.sidebar {
  position: sticky;
  top: 96px;
  align-self: start;
}

.card,
.sidebar-card,
.hero {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.sidebar-card {
  padding: 16px;
  margin-bottom: 16px;
}

.sidebar-card h3 {
  margin-top: 0;
  color: var(--accent);
}

.sidebar-card ul {
  margin: 0;
  padding-left: 18px;
}

.content {
  min-width: 0;
}

.hero {
  padding: 24px;
  margin-bottom: 18px;
  background:
    linear-gradient(135deg, rgba(56, 189, 248, 0.14), rgba(17, 31, 47, 0.96) 35%),
    rgba(17, 31, 47, 0.96);
}

.hero h1 {
  margin-top: 0;
  margin-bottom: 10px;
  color: var(--accent);
  font-size: 2rem;
}

.hero p {
  color: var(--muted);
  max-width: 980px;
}

.hero-grid,
.grid,
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.hero-stat {
  padding: 14px;
  border-radius: 14px;
  background: var(--panel-2);
  border: 1px solid #20364d;
}

.hero-stat strong,
.section-card h3,
h2, h3 {
  color: var(--accent);
}

.card {
  padding: 22px;
  margin-bottom: 18px;
}

.card h2 {
  margin-top: 0;
}

.section-card {
  background: var(--panel-2);
  border: 1px solid #20364d;
  border-radius: 14px;
  padding: 16px;
}

.badge {
  display: inline-block;
  padding: 3px 9px;
  border-radius: 999px;
  background: #13314a;
  color: #d9f3ff;
  font-size: 0.82rem;
  margin-right: 8px;
}

.badge.good { background: rgba(52, 211, 153, 0.16); color: #b7f7de; }
.badge.warn { background: rgba(245, 158, 11, 0.18); color: #fde5b1; }
.badge.danger { background: rgba(248, 113, 113, 0.18); color: #fecaca; }

.plain-box,
.specialist-box,
.note-box,
.math-box {
  border-radius: 14px;
  padding: 14px 16px;
  margin-top: 12px;
}

.plain-box {
  background: rgba(52, 211, 153, 0.08);
  border: 1px solid rgba(52, 211, 153, 0.22);
}

.specialist-box {
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.22);
}

.note-box {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.18);
}

.math-box {
  background: #0a1624;
  border: 1px solid #20364d;
}

.plain-box h3,
.specialist-box h3,
.note-box h3,
.math-box h3 {
  margin-top: 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 14px;
}

th, td {
  text-align: left;
  vertical-align: top;
  padding: 10px 12px;
  border-bottom: 1px solid #20364d;
}

th {
  color: var(--accent);
}

.toc a {
  display: block;
  padding: 6px 0;
}

.search-results {
  display: grid;
  gap: 12px;
}

.search-result {
  padding: 16px;
  border-radius: 14px;
  background: var(--panel-2);
  border: 1px solid #20364d;
}

.search-result h3 {
  margin: 0 0 8px;
}

figure.card img {
  width: 100%;
  height: auto;
  border-radius: 12px;
  border: 1px solid #20364d;
  background: #08111b;
}

figcaption {
  margin-top: 10px;
  color: var(--muted);
}

.footer {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px 40px;
  color: var(--muted);
}

.kicker {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-2);
  font-size: 0.8rem;
}

.screenshot-note {
  border-left: 4px solid var(--accent-2);
  padding-left: 12px;
  color: var(--muted);
}

math {
  font-size: 1.06rem;
}

@media (max-width: 1180px) {
  .header-inner {
    grid-template-columns: 1fr;
  }
  .layout {
    grid-template-columns: 1fr;
  }
  .sidebar {
    position: static;
  }
}