:root {
    --bg: #0f1419;
    --panel: #1a2028;
    --panel-2: #232b36;
    --border: #2d3744;
    --text: #e2e8f0;
    --text-dim: #94a3b8;
    --accent: #3dd68c;
    --accent-2: #4a9eff;
    --warn: #f6ad55;
    --danger: #fc8181;
    --grid: #2d3744;
    --canvas-bg: #131820;
    --hover-bg: #2a3441;
    --hover-row: rgba(255,255,255,0.02);
    --on-accent: #0f1419;
    --accent-grad: #2eb878;
    --shadow: 0 4px 12px rgba(0,0,0,0.3);
  }
  * { box-sizing: border-box; margin: 0; padding: 0; }
  html, body {
    background: var(--bg);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    font-size: 14px;
    line-height: 1.5;
    min-height: 100vh;
  }
  header {
    background: linear-gradient(135deg, var(--panel) 0%, var(--panel-2) 100%);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
  }
  header h1 {
    font-size: 18px;
    font-weight: 600;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }
  header .subtitle { color: var(--text-dim); font-size: 12px; }
  header .actions { display: flex; gap: 8px; }
  main {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }
  @media (max-width: 900px) { main { grid-template-columns: 1fr; } }
  .panel {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 16px;
    box-shadow: var(--shadow);
  }
  .panel.full { grid-column: 1 / -1; }
  .panel h2 {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }
  .panel h2 .badge {
    background: var(--panel-2);
    color: var(--text-dim);
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 11px;
    font-weight: normal;
    text-transform: none;
    letter-spacing: 0;
  }
  .row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
  .row > * { flex: 1; min-width: 0; }
  label { display: block; font-size: 12px; color: var(--text-dim); margin-bottom: 4px; }
  input, select, button {
    background: var(--panel-2);
    border: 1px solid var(--border);
    color: var(--text);
    padding: 7px 10px;
    border-radius: 5px;
    font-size: 13px;
    font-family: inherit;
    outline: none;
    transition: border-color 0.15s;
  }
  input:focus, select:focus { border-color: var(--accent-2); }
  input[type="number"] { width: 100%; }
  button {
    cursor: pointer;
    background: var(--panel-2);
    border: 1px solid var(--border);
    color: var(--text);
    padding: 7px 14px;
    border-radius: 5px;
    font-size: 13px;
    transition: all 0.15s;
    white-space: nowrap;
  }
  button:hover { border-color: var(--accent-2); background: var(--hover-bg); }
  button.primary {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-grad) 100%);
    border-color: transparent;
    color: var(--on-accent);
    font-weight: 600;
  }
  button.primary:hover { filter: brightness(1.1); }
  button.danger { color: var(--danger); }
  button.danger:hover { border-color: var(--danger); background: rgba(252,129,129,0.1); }
  button.small { padding: 4px 8px; font-size: 12px; }
  button:disabled { opacity: 0.4; cursor: not-allowed; }

  table { width: 100%; border-collapse: collapse; font-size: 12px; }
  th, td { padding: 6px 8px; text-align: left; border-bottom: 1px solid var(--border); }
  th { color: var(--text-dim); font-weight: 500; font-size: 11px; text-transform: uppercase; letter-spacing: 0.3px; }
  td input { padding: 4px 6px; font-size: 12px; width: 100%; }
  td.num { font-family: "SF Mono", Monaco, Consolas, monospace; }
  tr:hover { background: var(--hover-row); }
  .del-btn {
    background: transparent;
    border: none;
    color: var(--text-dim);
    padding: 2px 6px;
    cursor: pointer;
  }
  .del-btn:hover { color: var(--danger); }

  .params-list { display: flex; flex-direction: column; gap: 6px; margin-bottom: 8px; }
  .param-row {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 30px;
    gap: 6px;
    align-items: center;
  }
  .param-row input { padding: 5px 8px; font-size: 12px; }

  .result-card {
    background: var(--panel-2);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 12px;
    margin-bottom: 8px;
  }
  .result-card .label { font-size: 11px; color: var(--text-dim); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 6px; }
  .result-card .value { font-family: "SF Mono", Monaco, Consolas, monospace; font-size: 14px; color: var(--text); }
  .result-card .value.big { font-size: 16px; color: var(--accent); font-weight: 600; }
  .result-card .value.suggest { color: var(--accent-2); }
  .result-card .sub { font-size: 11px; color: var(--text-dim); margin-top: 4px; }
  .result-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
  .result-card.full { grid-column: 1 / -1; }

  .toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--panel-2);
    border: 1px solid var(--border);
    color: var(--text);
    padding: 10px 18px;
    border-radius: 6px;
    box-shadow: var(--shadow);
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.2s;
    pointer-events: none;
  }
  .toast.show { opacity: 1; }
  .toast.error { border-color: var(--danger); color: var(--danger); }
  .toast.success { border-color: var(--accent); color: var(--accent); }

  .viz-container { background: var(--panel-2); border-radius: 6px; padding: 8px; }
  canvas { display: block; width: 100%; height: auto; background: var(--canvas-bg); border-radius: 4px; }
  .viz-title { font-size: 12px; color: var(--text-dim); margin-bottom: 6px; display: flex; justify-content: space-between; }
  .viz-tabs { display: flex; gap: 4px; margin-bottom: 8px; flex-wrap: wrap; }
  .viz-tabs button {
    padding: 4px 10px;
    font-size: 12px;
    background: transparent;
    border: 1px solid var(--border);
  }
  .viz-tabs button.active { background: var(--accent-2); color: var(--on-accent); border-color: var(--accent-2); }

  .stats { display: flex; gap: 16px; flex-wrap: wrap; font-size: 12px; }
  .stat { color: var(--text-dim); }
  .stat b { color: var(--text); font-family: monospace; }

  .help { color: var(--text-dim); font-size: 11px; margin-top: 6px; line-height: 1.6; }
  .help code { background: var(--panel-2); padding: 1px 4px; border-radius: 3px; font-size: 11px; }

  .empty { color: var(--text-dim); font-style: italic; padding: 20px; text-align: center; font-size: 12px; }
  .scroll { max-height: 320px; overflow-y: auto; }
  .scroll::-webkit-scrollbar { width: 6px; }
  .scroll::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

  .tag {
    display: inline-block;
    padding: 1px 6px;
    border-radius: 3px;
    font-size: 10px;
    font-family: monospace;
    background: var(--panel-2);
    color: var(--text-dim);
  }
  .tag.green { background: rgba(61,214,140,0.15); color: var(--accent); }
  .tag.blue { background: rgba(74,158,255,0.15); color: var(--accent-2); }
  .tag.orange { background: rgba(246,173,85,0.15); color: var(--warn); }

  /* Light theme overrides */
  :root[data-theme="light"] {
    --bg: #f4f6f9;
    --panel: #ffffff;
    --panel-2: #eef2f7;
    --border: #d6dde6;
    --text: #1e293b;
    --text-dim: #64748b;
    --accent: #1ea86a;
    --accent-2: #2b7de9;
    --warn: #d97706;
    --danger: #e23b3b;
    --grid: #d6dde6;
    --canvas-bg: #ffffff;
    --hover-bg: #e2e8f0;
    --hover-row: rgba(15,23,42,0.04);
    --on-accent: #ffffff;
    --accent-grad: #168a55;
    --shadow: 0 4px 12px rgba(15,23,42,0.08);
  }
  :root[data-theme="light"] .toast { box-shadow: 0 4px 12px rgba(15,23,42,0.15); }
  :root[data-theme="light"] input[type="range"] { accent-color: var(--accent-2); }