:root {
  --bg: #0b1020;
  --card: #121a30;
  --text: #e6edf7;
  --muted: #9fb0cc;
  --link: #7cc4ff;
  --border: #253252;
  --code-bg: #0a0f1d;
}

:root[data-theme="light"] {
  --bg: #f5ecd7;
  --card: #fff8e7;
  --text: #3c2f1f;
  --muted: #7e6b4b;
  --link: #1f5fa8;
  --border: #d8c8a4;
  --code-bg: #f0e2c3;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 24px;
}

.topbar {
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

.topbar-main {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

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

.title {
  margin: 0;
  font-size: 28px;
}

.topbar-nav {
  margin-top: 12px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.nav-link {
  display: inline-block;
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text);
}

.nav-link.active {
  background: var(--card);
}

.theme-toggle {
  background: var(--card);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  cursor: pointer;
}

.theme-toggle:hover {
  text-decoration: underline;
}

.github-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  transition: all 0.2s ease;
}

.github-link:hover {
  color: var(--link);
  border-color: var(--link);
}

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

a:hover {
  text-decoration: underline;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.hero-card {
  background: linear-gradient(135deg, var(--card), color-mix(in srgb, var(--card) 82%, var(--bg)));
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 24px;
}

.hero-signature {
  margin: 0;
  font-size: 22px;
  line-height: 1.35;
  color: var(--muted);
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.photo-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.photo-item {
  display: block;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}

.photo-item img {
  display: block;
  width: 100%;
  height: 220px;
  object-fit: cover;
  cursor: zoom-in;
}

.lightbox {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 999;
}

.lightbox[hidden] {
  display: none;
}

.lightbox-image {
  max-width: min(1200px, 95vw);
  max-height: 90vh;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--card);
}

.lightbox-close {
  position: absolute;
  top: 14px;
  right: 18px;
  width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  font-size: 24px;
  line-height: 1;
  cursor: pointer;
}

.meta {
  color: var(--muted);
  font-size: 14px;
}

article {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
}

article h1,
article h2,
article h3 {
  line-height: 1.25;
}

article img {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 16px auto;
  border-radius: 10px;
  border: 1px solid var(--border);
}

article code {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2px 6px;
}

article pre {
  overflow-x: auto;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
}

.crumbs {
  margin-bottom: 16px;
}

.post-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 16px;
  align-items: start;
}

.post-toc {
  position: sticky;
  top: 16px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  max-height: calc(100vh - 40px);
  overflow: auto;
}

.post-toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 8px;
}

.post-toc-header h3 {
  margin: 0;
  font-size: 16px;
}

.toc-toggle {
  border: 1px solid var(--border);
  background: var(--code-bg);
  color: var(--text);
  border-radius: 8px;
  padding: 4px 8px;
  font-size: 12px;
  cursor: pointer;
}

.post-toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.toc-item {
  margin: 6px 0;
  line-height: 1.35;
}

.toc-item a.active {
  color: var(--text);
  font-weight: 700;
}

.toc-level-1 {
  padding-left: 10px;
}

.toc-level-2 {
  padding-left: 20px;
}

.toc-level-3,
.toc-level-4,
.toc-level-5 {
  padding-left: 30px;
}

.post-toc.is-collapsed .post-toc-list {
  display: none;
}

@media (max-width: 980px) {
  .post-layout {
    grid-template-columns: 1fr;
  }

  .post-toc {
    position: static;
    max-height: none;
    order: -1;
  }
}