:root {
  --bg: #0f1115;
  --bg-elevated: #171a21;
  --bg-card: #1c212b;
  --bg-card-hover: #232936;
  --border: #2a3140;
  --text: #e8eaed;
  --text-muted: #9aa3b2;
  --text-dim: #6b7385;
  --accent: #7c9cff;
  --accent-soft: rgba(124, 156, 255, 0.12);
  --chip: #252b38;
  --chip-active: #7c9cff;
  --chip-active-text: #0f1115;
  --tag-ai: #5b8def;
  --tag-arch: #6bcf8e;
  --tag-grow: #e0a458;
  --tag-conf: #c084fc;
  --sample: #8b93a7;
  --danger-soft: rgba(224, 164, 88, 0.15);
  --radius: 14px;
  --shadow: 0 8px 28px rgba(0, 0, 0, 0.35);
  --font: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --max: 720px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.app {
  max-width: var(--max);
  margin: 0 auto;
  padding: 1.25rem 1rem 4rem;
}

.topbar {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  margin-bottom: 1.5rem;
  padding-top: 0.5rem;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.brand h1 {
  font-size: 1.45rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0;
}

.brand .badge {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.2rem 0.5rem;
  border-radius: 999px;
  font-weight: 600;
}

.subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0;
}

.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 1.25rem 0 1rem;
  position: sticky;
  top: 0;
  z-index: 10;
  padding: 0.65rem 0;
  background: linear-gradient(to bottom, var(--bg) 70%, transparent);
}

.chip {
  appearance: none;
  border: 1px solid var(--border);
  background: var(--chip);
  color: var(--text-muted);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.chip:hover { border-color: var(--accent); color: var(--text); }
.chip.active {
  background: var(--chip-active);
  border-color: var(--chip-active);
  color: var(--chip-active-text);
}

.meta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-dim);
  font-size: 0.8rem;
  margin-bottom: 0.75rem;
}

.feed {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.day-header {
  margin: 1.25rem 0 0.35rem;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.05rem;
  box-shadow: none;
  transition: background 0.15s, border-color 0.15s;
}

.card:hover { background: var(--bg-card-hover); border-color: #343c4f; }
.card.open { box-shadow: var(--shadow); }

.card-head {
  display: flex;
  gap: 0.65rem;
  align-items: flex-start;
  cursor: pointer;
  user-select: none;
}

.card-head:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 8px;
}

.card-main { flex: 1; min-width: 0; }

.tag {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 0.15rem 0.45rem;
  border-radius: 6px;
  margin-bottom: 0.35rem;
  color: #0f1115;
}

.tag-ai { background: var(--tag-ai); }
.tag-architecture { background: var(--tag-arch); }
.tag-grow { background: var(--tag-grow); }
.tag-conference { background: var(--tag-conf); }

.card h2 {
  font-size: 1.05rem;
  font-weight: 650;
  letter-spacing: -0.015em;
  margin: 0 0 0.35rem;
  line-height: 1.35;
}

.card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.75rem;
  font-size: 0.78rem;
  color: var(--text-dim);
}

.sample-pill {
  color: var(--sample);
  background: var(--danger-soft);
  padding: 0.1rem 0.4rem;
  border-radius: 999px;
  font-weight: 600;
}

.chevron {
  color: var(--text-dim);
  font-size: 1.1rem;
  line-height: 1;
  margin-top: 0.15rem;
  transition: transform 0.2s;
}
.card.open .chevron { transform: rotate(180deg); }

.card-body {
  display: none;
  margin-top: 0.85rem;
  padding-top: 0.85rem;
  border-top: 1px solid var(--border);
}
.card.open .card-body { display: block; }

.summary {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0 0 0.9rem;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  align-items: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.45rem 0.75rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  text-decoration: none !important;
}
.btn:hover { border-color: var(--accent); color: var(--accent); }
.btn-primary {
  background: var(--accent-soft);
  border-color: transparent;
  color: var(--accent);
}

.video-wrap {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  height: 0;
  margin: 0.85rem 0 0.25rem;
  border-radius: 12px;
  overflow: hidden;
  background: #000;
  border: 1px solid var(--border);
}
.video-wrap iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.empty {
  text-align: center;
  color: var(--text-muted);
  padding: 2.5rem 1rem;
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}

.footer {
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  color: var(--text-dim);
  font-size: 0.78rem;
  text-align: center;
}

@media (min-width: 640px) {
  .app { padding: 2rem 1.25rem 4rem; }
  .brand h1 { font-size: 1.7rem; }
  .card { padding: 1.15rem 1.25rem; }
  .card h2 { font-size: 1.12rem; }
}