:root {
  color-scheme: light dark;
  --bg: #f5f6f8;
  --card-bg: #ffffff;
  --text: #1c1e21;
  --muted: #6b7280;
  --accent: #2563eb;
  --border: #e5e7eb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #15171c;
    --card-bg: #1f2229;
    --text: #f0f1f3;
    --muted: #9aa1ac;
    --accent: #6ea8fe;
    --border: #2c2f37;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  background: var(--bg);
  color: var(--text);
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
  gap: 12px;
}

.header h1 {
  font-size: 20px;
  margin: 0;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.updated-at {
  font-size: 13px;
  color: var(--muted);
}

#refresh-button {
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  cursor: pointer;
}

#refresh-button:disabled {
  opacity: 0.6;
  cursor: default;
}

.category-tabs {
  display: flex;
  gap: 8px;
  padding: 12px 24px;
  overflow-x: auto;
}

.category-tabs button {
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card-bg);
  color: var(--text);
  font-size: 13px;
  cursor: pointer;
  white-space: nowrap;
}

.category-tabs button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

main {
  max-width: 880px;
  margin: 0 auto;
  padding: 16px 24px 60px;
}

.x-links-section {
  margin-bottom: 20px;
}

.section-title {
  font-size: 13px;
  color: var(--muted);
  margin: 0 0 8px;
  font-weight: 600;
}

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

.x-link-card {
  display: inline-block;
  padding: 8px 14px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--card-bg);
  color: var(--text);
  text-decoration: none;
  font-size: 13px;
  font-weight: 600;
}

.x-link-card:hover {
  color: var(--accent);
  border-color: var(--accent);
}

.loading,
.empty-state {
  text-align: center;
  color: var(--muted);
  padding: 40px 0;
}

.error-banner {
  background: #fef2f2;
  color: #b91c1c;
  border: 1px solid #fecaca;
  border-radius: 8px;
  padding: 12px 16px;
  margin-bottom: 16px;
  font-size: 13px;
}

@media (prefers-color-scheme: dark) {
  .error-banner {
    background: #3a1f1f;
    color: #fca5a5;
    border-color: #5c2b2b;
  }
}

.item-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.item-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px 16px;
}

.item-card a {
  color: var(--text);
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
}

.item-card a:hover {
  color: var(--accent);
}

.item-meta {
  margin-top: 6px;
  font-size: 12px;
  color: var(--muted);
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.item-meta .badge {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px 8px;
}