:root {
  --bg: #0a0e17;
  --surface: #111827;
  --surface2: #1a2235;
  --border: #1e293b;
  --text: #e2e8f0;
  --text-dim: #94a3b8;
  --green: #22c55e;
  --green-dim: #16a34a;
  --green-bg: rgba(34,197,94,0.08);
  --red: #ef4444;
  --red-dim: #dc2626;
  --red-bg: rgba(239,68,68,0.08);
  --gold: #f59e0b;
  --silver: #a1a1aa;
  --accent: #6366f1;
}

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

body {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

.container { max-width: 1400px; margin: 0 auto; padding: 20px; }

/* Header */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}
header h1 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
header h1 span.gold { color: var(--gold); }
header h1 span.silver { color: var(--silver); }
.header-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 13px;
  color: var(--text-dim);
}
.live-dot {
  width: 8px; height: 8px;
  background: var(--green);
  border-radius: 50%;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}
#refresh-btn {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  font-size: 13px;
  transition: background 0.2s;
}
#refresh-btn:hover { background: var(--accent); }
#refresh-btn:disabled { opacity: 0.5; cursor: not-allowed; }

.period-selector {
  display: flex;
  gap: 8px;
}
.period-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  font-size: 12px;
  font-weight: 500;
  transition: all 0.2s;
}
.period-btn:hover { border-color: var(--accent); color: var(--text); }
.period-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }

/* Stats bar */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-bottom: 24px;
}
.stat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 20px;
}
.stat-card .label { font-size: 11px; color: var(--text-dim); text-transform: uppercase; letter-spacing: 1px; }
.stat-card .value { font-size: 26px; font-weight: 700; margin-top: 4px; }
.stat-card .value.green { color: var(--green); }
.stat-card .value.red { color: var(--red); }

/* Heatmap section */
.section-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-title .badge {
  font-size: 11px;
  background: var(--accent);
  color: #fff;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 500;
}

.heatmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 16px;
  margin-bottom: 32px;
}
.heatmap-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  position: relative;
  overflow: hidden;
}
.heatmap-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
}
.heatmap-card.gld::before { background: var(--gold); }
.heatmap-card.slv::before { background: var(--silver); }

.heatmap-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 16px;
}
.heatmap-card h3 .ticker-gld { color: var(--gold); }
.heatmap-card h3 .ticker-slv { color: var(--silver); }

.heatmap-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
}
.heatmap-row:last-child { border-bottom: none; }
.heatmap-row .label { color: var(--text-dim); }

.bar-container {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  height: 28px;
}
.bar-label { font-size: 11px; width: 40px; text-align: right; color: var(--text-dim); }
.bar-track {
  flex: 1;
  height: 20px;
  background: var(--surface2);
  border-radius: 4px;
  overflow: hidden;
  position: relative;
}
.bar-fill {
  height: 100%;
  border-radius: 4px;
  transition: width 0.6s ease;
}
.bar-fill.call { background: var(--green); opacity: 0.7; }
.bar-fill.put { background: var(--red); opacity: 0.7; }

/* Expiration heatmap */
.exp-heatmap {
  margin-bottom: 32px;
}
.exp-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 8px;
}
.exp-cell {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  text-align: center;
  font-size: 12px;
  transition: transform 0.2s;
  cursor: default;
}
.exp-cell:hover { transform: translateY(-2px); }
.exp-cell .exp-date { font-weight: 600; margin-bottom: 4px; }
.exp-cell .exp-ticker { font-size: 10px; color: var(--text-dim); }
.exp-cell .exp-vol { font-size: 11px; margin-top: 4px; }
.exp-cell .exp-unusual {
  display: inline-block;
  margin-top: 4px;
  font-size: 10px;
  background: rgba(99,102,241,0.2);
  color: var(--accent);
  padding: 1px 6px;
  border-radius: 3px;
}
.heat-0 { border-color: var(--border); }
.heat-1 { border-color: rgba(99,102,241,0.3); background: rgba(99,102,241,0.03); }
.heat-2 { border-color: rgba(99,102,241,0.5); background: rgba(99,102,241,0.06); }
.heat-3 { border-color: rgba(99,102,241,0.7); background: rgba(99,102,241,0.1); }
.heat-4 { border-color: var(--accent); background: rgba(99,102,241,0.15); }

/* Notable trades table */
.table-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}
.sort-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 5px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  font-size: 12px;
  transition: all 0.2s;
}
.sort-btn:hover { border-color: var(--accent); color: var(--text); }
.sort-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }
.sort-btn .arrow { margin-left: 4px; font-size: 10px; }

.filter-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 5px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  font-size: 12px;
  transition: all 0.2s;
}
.filter-btn:hover { border-color: var(--accent); color: var(--text); }
.filter-btn.active { background: var(--surface2); border-color: var(--accent); color: var(--text); }

.table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
thead th {
  padding: 12px 14px;
  text-align: left;
  font-weight: 600;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-dim);
  background: var(--surface2);
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
  cursor: pointer;
  user-select: none;
}
thead th:hover { color: var(--text); }
tbody tr {
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}
tbody tr:last-child { border-bottom: none; }
tbody tr:hover { background: var(--surface2); }
tbody td {
  padding: 10px 14px;
  white-space: nowrap;
}

.call-row { background: var(--green-bg); }
.put-row { background: var(--red-bg); }

.badge-call {
  background: rgba(34,197,94,0.15);
  color: var(--green);
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
  font-size: 11px;
}
.badge-put {
  background: rgba(239,68,68,0.15);
  color: var(--red);
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
  font-size: 11px;
}
.badge-unusual {
  background: rgba(245,158,11,0.15);
  color: var(--gold);
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
  font-size: 11px;
}

.premium-val { font-weight: 700; }
.ratio-hot { color: var(--gold); font-weight: 600; }

.ticker-gld { color: var(--gold); font-weight: 700; }
.ticker-slv { color: var(--silver); font-weight: 700; }

/* Loading */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(10,14,23,0.92);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  gap: 16px;
}
.spinner {
  width: 40px; height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading-text { color: var(--text-dim); font-size: 14px; }

/* Empty state */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-dim);
}
.empty-state p { margin-top: 8px; font-size: 14px; }

/* Responsive — tablets */
@media (max-width: 768px) {
  .container { padding: 12px; }
  header { flex-direction: column; gap: 12px; align-items: flex-start; }
  header h1 { font-size: 18px; }
  .header-meta { flex-wrap: wrap; gap: 10px; width: 100%; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); }
  .heatmap-grid { grid-template-columns: 1fr; }
  .table-controls { gap: 8px; }
  .sort-btn, .filter-btn { padding: 8px 12px; font-size: 13px; }
  thead th { padding: 10px 10px; font-size: 10px; }
  tbody td { padding: 8px 10px; font-size: 12px; }
}

/* Responsive — phones */
@media (max-width: 480px) {
  .container { padding: 8px; }
  header h1 { font-size: 16px; }
  .header-meta { font-size: 12px; }
  .period-btn { padding: 8px 14px; font-size: 13px; }
  #refresh-btn { padding: 8px 14px; font-size: 13px; }
  #timestamp { display: none; }
  .stats-bar { grid-template-columns: repeat(2, 1fr); gap: 8px; }
  .stat-card { padding: 12px; }
  .stat-card .value { font-size: 20px; }
  .stat-card .label { font-size: 10px; }
  .section-title { font-size: 14px; }
  .heatmap-grid { grid-template-columns: 1fr; }
  .exp-grid { grid-template-columns: repeat(auto-fill, minmax(110px, 1fr)); gap: 6px; }
  .exp-cell { padding: 8px; }
  .table-controls {
    gap: 6px;
  }
  .table-controls > span[style] { display: none; }
  .sort-btn, .filter-btn { padding: 7px 10px; font-size: 12px; }
  thead th { padding: 8px 6px; font-size: 10px; letter-spacing: 0.3px; }
  tbody td { padding: 8px 6px; font-size: 11px; }
}