:root {
  --bg: #f6f7f9;
  --panel: #ffffff;
  --line: #e3e6ea;
  --text: #1f2430;
  --muted: #6b7280;
  --brand: #4f5bd5;
  --brand-weak: #eef0fc;
  --err: #c0392b;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.6 "Segoe UI", "Microsoft YaHei", system-ui, sans-serif;
}
.layout { display: flex; min-height: 100vh; }

.sidebar {
  width: 220px; flex-shrink: 0;
  background: var(--panel); border-right: 1px solid var(--line);
  padding: 18px 14px; display: flex; flex-direction: column; gap: 10px;
}
.brand { font-weight: 700; font-size: 17px; padding: 4px 8px 10px; }
#tool-nav { display: flex; flex-direction: column; gap: 2px; }
#tool-nav button {
  all: unset; cursor: pointer; padding: 8px 10px; border-radius: 8px;
  color: var(--text); font-size: 14px;
}
#tool-nav button:hover { background: var(--brand-weak); }
#tool-nav button.active { background: var(--brand); color: #fff; }
.sidebar-foot { margin-top: auto; font-size: 13px; }
.sidebar-foot a { color: var(--muted); text-decoration: none; }
.sidebar-foot a:hover { color: var(--brand); }

.main { flex: 1; padding: 26px 30px; max-width: 900px; }
.tool-panel h2 { margin: 0 0 4px; font-size: 20px; }
.hint { margin: 0 0 14px; color: var(--muted); font-size: 13px; }

textarea, input[type="text"], input[type="number"], input[type="datetime-local"] {
  width: 100%; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px;
  font: 14px/1.55 Consolas, "Courier New", monospace; background: var(--panel); color: var(--text);
}
textarea { min-height: 110px; resize: vertical; }
textarea:focus, input:focus { outline: 2px solid var(--brand-weak); border-color: var(--brand); }

.row { display: flex; gap: 8px; margin: 10px 0; flex-wrap: wrap; }
.field-row { display: flex; gap: 8px; margin: 10px 0; flex-wrap: wrap; }
.field-row input { flex: 1; min-width: 200px; width: auto; }

.btn {
  all: unset; cursor: pointer; padding: 8px 16px; border-radius: 8px;
  background: var(--brand); color: #fff; font-size: 14px; text-align: center;
}
.btn:hover { filter: brightness(1.08); }
.btn.ghost { background: var(--brand-weak); color: var(--brand); }
.btn.ghost:hover { filter: brightness(0.97); }

.kv-out { margin-top: 10px; font-size: 14px; }
.kv-out .kv {
  display: flex; gap: 10px; padding: 8px 10px; background: var(--panel);
  border: 1px solid var(--line); border-radius: 8px; margin-bottom: 6px; align-items: baseline;
}
.kv-out .kv b { color: var(--muted); font-weight: 600; white-space: nowrap; font-size: 13px; }
.kv-out .kv code { word-break: break-all; font-family: Consolas, monospace; }

.err {
  margin: 8px 0; padding: 8px 12px; border-radius: 8px;
  background: #fdf0ee; color: var(--err); font-size: 13px;
}

.stat-grid {
  margin-top: 12px; display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px;
}
.stat-grid .cell {
  background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px;
}
.stat-grid .cell .num { font-size: 22px; font-weight: 700; }
.stat-grid .cell .lbl { color: var(--muted); font-size: 12px; }

.foot { margin-top: 30px; padding-top: 14px; border-top: 1px solid var(--line); font-size: 13px; color: var(--muted); }
.swatch {
  width: 42px; height: 42px; border-radius: 10px; flex-shrink: 0;
  border: 1px solid var(--line); background: transparent;
}
.foot a { color: var(--muted); text-decoration: none; margin-right: 2px; }
.foot a:hover { color: var(--brand); }
.foot-note { display: block; margin-top: 6px; font-size: 12px; }

hr { border: none; border-top: 1px solid var(--line); margin: 16px 0; }

@media (max-width: 640px) {
  .layout { flex-direction: column; }
  .sidebar {
    width: 100%; border-right: none; border-bottom: 1px solid var(--line);
    position: sticky; top: 0; z-index: 10;
    padding: 10px 12px; gap: 6px;
  }
  .brand { padding: 2px 4px 6px; font-size: 15px; }
  .sidebar-foot { display: none; }
  #tool-nav {
    flex-direction: row; flex-wrap: nowrap;
    overflow-x: auto; -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  #tool-nav::-webkit-scrollbar { display: none; }
  #tool-nav button { white-space: nowrap; flex-shrink: 0; padding: 6px 12px; font-size: 13px; }
  .main { padding: 18px 14px; }
}