:root {
  --bg: #0b0f14;
  --card: #121821;
  --muted: #273142;
  --text: #e8f0ff;
  --accent: #4da3ff;
  --accent-2: #00d2a8;
  --danger: #ff5d5d;
  --border: #2a3647;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: linear-gradient(180deg, #0b0f14, #151b26 40%, #0b0f14);
  color: var(--text);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
  background: rgba(18,24,33,0.8);
  backdrop-filter: blur(8px);
  position: sticky; top: 0; z-index: 9;
}
.topbar h1 { margin: 0; font-size: 18px; letter-spacing: 1px; }
.topbar .actions button { margin-left: 8px; }

.layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  min-height: calc(100vh - 56px);
}

.sidebar {
  border-right: 1px solid var(--border);
  padding: 12px;
  background: rgba(18,24,33,0.6);
}

.search input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  outline: none;
}

.tree { margin-top: 10px; font-size: 14px; }
.tree details { margin: 4px 0; }
.tree summary { cursor: pointer; color: #cdd8f3; }
.tree .item { padding: 4px 6px; border-radius: 6px; cursor: pointer; }
.tree .item:hover { background: #192232; }

.content { padding: 16px; }
.card {
  background: rgba(18,24,33,0.6);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.25);
}

.form.hidden { display: none; }

.form label { display: block; margin: 10px 0; }
.form input, .form textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  outline: none;
}
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.form-actions { margin-top: 12px; }

button {
  padding: 8px 14px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #1a2535;
  color: var(--text);
  cursor: pointer;
}
button:hover { border-color: var(--accent); }
button.secondary { background: #1a1f29; }
button.danger { background: #2a1220; border-color: #3a1a27; color: #ffb3c2; }