/* Sunscreen — typography, spacing, hero. Editorial dark-first. */

:root {
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --content-max-width: 820px;
  --sidebar-width: 360px;

  --radius-sm: 5px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

html, body {
  font-family: var(--font-sans);
  font-feature-settings: "ss01", "cv11";
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  background: var(--bg);
  color: var(--fg);
}

/* Content column */
.content main {
  max-width: var(--content-max-width);
  padding-top: 3.5rem;
  padding-bottom: 6rem;
}

/* Headings: editorial scale, tight tracking. */
.content h1,
.content h2,
.content h3,
.content h4,
.content h5,
.content h6 {
  color: var(--fg-strong);
  font-weight: 650;
}

.content h1 {
  font-size: 2.8rem;
  line-height: 1.12;
  letter-spacing: -0.025em;
  font-weight: 700;
  margin-top: 0;
  margin-bottom: 1.75rem;
}

.content h2 {
  font-size: 1.85rem;
  line-height: 1.25;
  letter-spacing: -0.018em;
  margin-top: 3.5rem;
  margin-bottom: 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.content h3 {
  font-size: 1.35rem;
  line-height: 1.35;
  letter-spacing: -0.01em;
  margin-top: 2.4rem;
  margin-bottom: 0.6rem;
}

.content h4 {
  font-size: 0.88rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--fg-muted);
  margin-top: 1.8rem;
  margin-bottom: 0.5rem;
}

.content p,
.content li {
  color: var(--fg);
}

.content p {
  margin: 0 0 1.15rem 0;
}

.content ul,
.content ol {
  padding-left: 1.4rem;
  margin: 0 0 1.2rem 0;
}
.content li {
  margin: 0.3rem 0;
}
.content li::marker {
  color: var(--fg-faint);
}

.content hr {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 3rem 0;
}

/* Links */
.content a {
  color: var(--brand);
  text-decoration: none;
  border-bottom: 1px solid var(--border-strong);
  transition: border-color 100ms ease, color 100ms ease;
}
.content a:hover {
  color: var(--brand-soft);
  border-bottom-color: var(--brand);
}

/* Inline code */
.content code {
  font-family: var(--font-mono);
  font-size: 0.93em;
  background: var(--bg-inline-code);
  color: var(--inline-code-color);
  padding: 0.12em 0.42em;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

/* Code blocks — calm, no heavy shadow */
.content pre {
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.05rem 1.2rem;
  overflow-x: auto;
  box-shadow: none;
  margin: 1.4rem 0;
}
.content pre code {
  background: transparent;
  border: none;
  padding: 0;
  font-size: 16px;
  line-height: 1.65;
  color: var(--fg);
}

/* Blockquotes */
.content blockquote {
  background: transparent;
  border-left: 2px solid var(--brand);
  padding: 0.2rem 0 0.2rem 1.2rem;
  margin: 1.6rem 0;
  border-radius: 0;
  color: var(--fg-muted);
  font-style: normal;
}
.content blockquote p:last-child { margin-bottom: 0; }

/* Tables */
.content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.6rem 0;
  font-size: 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.content table th {
  background: var(--table-header-bg);
  text-align: left;
  font-weight: 600;
  padding: 0.7rem 1rem;
  color: var(--fg-strong);
  border-bottom: 1px solid var(--border-strong);
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.content table td {
  padding: 0.7rem 1rem;
  border-top: 1px solid var(--border);
}
.content table tr:nth-child(even) td {
  background: transparent;
}

/* Sidebar — quiet, sunken, editorial */
.sidebar {
  font-size: 16px;
  border-right: 1px solid var(--border);
  width: var(--sidebar-width);
  background: var(--sidebar-bg);
}
.sidebar .sidebar-scrollbox {
  padding: 1.4rem 0.9rem 2rem;
  font-size: 16px;
}
.sidebar .chapter li.chapter-item {
  padding: 0;
  margin: 0.1rem 0;
  line-height: 1.5;
  font-size: 16px;
}
.sidebar .chapter li.chapter-item a {
  color: var(--fg-muted);
  font-size: 16px;
  padding: 0.48rem 0.85rem;
  border-radius: var(--radius-sm);
  transition: background 90ms ease, color 90ms ease;
  border-bottom: none;
}
.sidebar .chapter li.chapter-item a:hover {
  background: transparent;
  color: var(--fg-strong);
}
.sidebar .chapter li.chapter-item a.active {
  color: var(--brand);
  background: var(--brand-tint);
  font-weight: 600;
}
.sidebar .chapter li.spacer {
  border-top: 1px solid var(--border);
  margin: 0.8rem 0.4rem;
}
.sidebar .part-title {
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 14px;
  color: var(--fg-faint);
  font-weight: 700;
  padding: 1.6rem 0.85rem 0.6rem;
}

/* Top menu */
.menu-bar {
  border-bottom: 1px solid var(--border);
}
.menu-title {
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--fg-strong);
}
.icon-button {
  color: var(--icons);
}
.icon-button:hover {
  color: var(--icons-hover);
}

/* Search */
#searchbar {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--searchbar-bg);
  color: var(--fg);
}
#searchbar:focus {
  border-color: var(--brand);
  outline: none;
}

/* Hero on landing */
.hero-cta {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin: 1.75rem 0 2.5rem 0;
}
.content .hero-cta a {
  display: inline-block;
  padding: 0.7rem 1.25rem;
  border-radius: var(--radius-md);
  background: var(--brand);
  color: #14110B;
  font-weight: 600;
  border-bottom: none;
  font-size: 1rem;
  transition: transform 100ms ease, background 100ms ease;
}
.content .hero-cta a:hover {
  background: var(--brand-soft);
  color: #14110B;
  border-bottom: none;
  transform: translateY(-1px);
}
.content .hero-cta a:nth-child(2) {
  background: transparent;
  color: var(--fg-strong);
  border: 1px solid var(--border-strong);
}
.content .hero-cta a:nth-child(2):hover {
  background: var(--bg-elevated);
  border-color: var(--brand);
  color: var(--brand);
}

/* Card grid on landing */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0 3rem 0;
}
.card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.4rem 1.5rem;
  transition: border-color 120ms ease, transform 120ms ease;
}
.card:hover {
  border-color: var(--brand);
  transform: translateY(-1px);
}
.card h3 {
  margin-top: 0 !important;
  margin-bottom: 0.7rem !important;
  font-size: 2.4rem !important;
  line-height: 1.2 !important;
}
.card p {
  color: var(--fg-muted);
  font-size: 1.5rem !important;
  line-height: 1.55 !important;
  margin-bottom: 1.25rem;
}
.content .card a {
  color: var(--brand);
  font-weight: 600;
  border-bottom: none;
  font-size: 1.45rem;
}
.card a:hover {
  color: var(--brand-soft);
  border-bottom: none;
}

/* Selection */
::selection {
  background: var(--brand);
  color: #14110B;
}

/* Scrollbars (webkit) */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 6px;
}
::-webkit-scrollbar-thumb:hover { background: var(--fg-muted); }

/* Focus visible — accessibility */
a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Reduce motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none !important;
    animation: none !important;
  }
}

/* Narrow viewport tweaks */
@media (max-width: 768px) {
  html, body { font-size: 17px; }
  .content h1 { font-size: 2.2rem; }
  .content h2 { font-size: 1.55rem; }
  .content main { padding-top: 2rem; }
  .sidebar { font-size: 16px; }
}