:root {
  --bg: #0a0a0a;
  --surface: #111111;
  --surface-hover: #1a1a1a;
  --border: #1e1e1e;
  --text: #e0e0e0;
  --text-dim: #666;
  --accent: #4f8fff;
  --pill-bg: #1a1a1a;
  --pill-active: #4f8fff;
  --radius: 10px;
  --max-w: 640px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* header */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10,10,10,0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.logo {
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.5px;
}

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

.search-box input {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 12px;
  color: var(--text);
  font-size: 14px;
  width: 160px;
  outline: none;
  transition: border-color 0.2s;
}

.search-box input:focus {
  border-color: var(--accent);
}

.rss-link {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-dim);
  letter-spacing: 0.5px;
}
.rss-link:hover { color: var(--text); }

/* topic bar */
.topic-bar {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 10px 16px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}
.topic-bar::-webkit-scrollbar { display: none; }

.topic-pill {
  background: var(--pill-bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 13px;
  color: var(--text-dim);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.15s;
}
.topic-pill:hover {
  color: var(--text);
  border-color: #333;
}
.topic-pill.active {
  background: var(--pill-active);
  border-color: var(--pill-active);
  color: #fff;
  font-weight: 500;
}

/* feed */
main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 16px 60px;
}

.card {
  display: block;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
  transition: opacity 0.1s;
}
.card:hover { opacity: 0.88; }

.card-topic {
  display: inline-block;
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 6px;
  letter-spacing: 0.2px;
}

.card-headline {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.35;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 6px;
}

.card-summary {
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 8px;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-dim);
}

.card-source { font-weight: 500; }

.card-dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--text-dim);
}

.card-reactions {
  display: flex;
  align-items: center;
  gap: 3px;
  margin-left: auto;
}

/* loader / empty */
.loader, .empty {
  text-align: center;
  padding: 40px 16px;
  color: var(--text-dim);
  font-size: 14px;
}
.hidden { display: none; }

/* responsive */
@media (max-width: 480px) {
  .search-box input { width: 120px; }
  .card-headline { font-size: 15px; }
}