/* Viden — knowledge base */

.viden-hero {
  padding: 80px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--sep);
}
.viden-hero h1 {
  font-size: clamp(36px, 5vw, 56px);
  font-weight: 800;
  letter-spacing: -.02em;
  margin: 12px 0 16px;
  line-height: 1.05;
}
.viden-hero p {
  color: var(--text-sec);
  font-size: 17px;
  max-width: 580px;
  margin: 0 auto;
}

.viden-search {
  max-width: 640px;
  margin: 32px auto 0;
  position: relative;
}
.viden-search input {
  width: 100%;
  box-sizing: border-box;
  padding: 16px 20px 16px 52px;
  font-size: 17px;
  font-family: inherit;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--sep);
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
  transition: border-color .15s ease, box-shadow .15s ease;
}
.viden-search input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(4, 54, 21, .08), var(--shadow-sm);
}
.viden-search input::placeholder { color: var(--text-ter); }
.viden-search-icon {
  position: absolute;
  left: 20px;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  color: var(--text-ter);
  pointer-events: none;
}

.viden-content {
  padding: 64px 0 96px;
}
.viden-empty {
  display: none;
  text-align: center;
  padding: 64px 0;
  color: var(--text-sec);
}
.viden-empty.show { display: block; }
.viden-empty p { font-size: 16px; margin: 0; }

.viden-section { margin-bottom: 64px; }
.viden-section.hidden { display: none; }
.viden-section h2 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 0 0 24px;
  color: var(--text);
}

.viden-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}
.viden-card {
  display: block;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--sep);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: transform .15s ease, box-shadow .15s ease, border-color .15s ease;
}
.viden-card.hidden { display: none; }
.viden-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: rgba(4, 54, 21, .15);
}
.viden-card h3 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -.005em;
  margin: 0 0 8px;
  color: var(--text);
}
.viden-card p {
  margin: 0;
  font-size: 14px;
  color: var(--text-sec);
  line-height: 1.5;
}
.viden-card mark {
  background: rgba(4, 54, 21, .12);
  color: inherit;
  padding: 1px 2px;
  border-radius: 2px;
}

/* Article page */
.viden-article {
  padding: 64px 0 96px;
}
.viden-article-wrap {
  max-width: 720px;
  margin: 0 auto;
}
.viden-breadcrumb {
  font-size: 14px;
  color: var(--text-ter);
  margin-bottom: 16px;
}
.viden-breadcrumb a {
  color: var(--text-ter);
  text-decoration: none;
}
.viden-breadcrumb a:hover { color: var(--accent); }
.viden-article h1 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.15;
  margin: 0 0 12px;
}
.viden-article .lede {
  font-size: 18px;
  color: var(--text-sec);
  line-height: 1.55;
  margin: 0 0 40px;
}
.viden-article h2 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 48px 0 16px;
}
.viden-article h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 32px 0 12px;
}
.viden-article p,
.viden-article li {
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
}
.viden-article p { margin: 0 0 16px; }
.viden-article ul, .viden-article ol {
  margin: 0 0 16px;
  padding-left: 24px;
}
.viden-article li { margin-bottom: 6px; }
.viden-article a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: rgba(4, 54, 21, .3);
  text-underline-offset: 3px;
}
.viden-article a:hover { text-decoration-color: var(--accent); }
.viden-article code {
  background: #f5f5f4;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.92em;
}
.viden-article pre {
  background: #1c1917;
  color: #f5f5f4;
  padding: 16px 20px;
  border-radius: 12px;
  overflow-x: auto;
  font-size: 14px;
  line-height: 1.5;
  margin: 16px 0;
}
.viden-article pre code {
  background: transparent;
  padding: 0;
  color: inherit;
  font-size: inherit;
}
.viden-article blockquote {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 20px;
  margin: 16px 0;
  color: var(--text-sec);
  font-style: italic;
}
.viden-callout {
  background: #f5f5f4;
  border-left: 3px solid var(--accent);
  padding: 16px 20px;
  border-radius: 8px;
  margin: 24px 0;
}
.viden-callout strong { color: var(--text); }
.viden-callout p:last-child { margin-bottom: 0; }

.viden-related {
  margin-top: 80px;
  padding-top: 40px;
  border-top: 1px solid var(--sep);
}
.viden-related h2 {
  font-size: 18px;
  margin: 0 0 16px;
}
.viden-related ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.viden-related li {
  margin-bottom: 8px;
}
.viden-related a {
  color: var(--accent);
  text-decoration: none;
  font-size: 15px;
}
.viden-related a:hover { text-decoration: underline; }

.viden-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--accent);
  background: rgba(4, 54, 21, .08);
  padding: 3px 8px;
  border-radius: 6px;
  margin-bottom: 12px;
}