:root {
  --bg: #111827;
  --panel: #0b1220;
  --panel-2: #0f172a;
  --border: #243041;
  --border-soft: #1f2937;
  --text: #e5e7eb;
  --muted: #fbbf24;
  --dir: #93c5fd;
  --hover: #172033;
  --button-bg: #111827;
  --overlay: rgba(0,0,0,0.45);
}

body[data-theme="light"] {
  --bg: #f8fafc;
  --panel: #ffffff;
  --panel-2: #f1f5f9;
  --border: #dbe3ee;
  --border-soft: #e5e7eb;
  --text: #0f172a;
  --muted: #b45309;
  --dir: #1d4ed8;
  --hover: #eef2ff;
  --button-bg: #ffffff;
  --overlay: rgba(15,23,42,0.22);
}

html, body { margin: 0; height: 100%; font-family: Inter, system-ui, sans-serif; background: var(--bg); color: var(--text); }
* { box-sizing: border-box; }
#app { display: grid; grid-template-columns: 320px 1fr; height: 100vh; }
.sidebar { border-right: 1px solid var(--border); overflow: auto; background: var(--panel); }
main { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.sidebar-header, .topbar { padding: 12px 16px; border-bottom: 1px solid var(--border); background: var(--panel-2); }
#editor { flex: 1; min-height: 0; }
#tree { padding: 8px; }
.node { padding: 7px 8px; cursor: pointer; border-radius: 6px; font-size: 14px; line-height: 1.35; }
.node:hover { background: var(--hover); }
.dir { color: var(--dir); font-weight: 600; }
.file { color: var(--text); }
.children { margin-left: 14px; border-left: 1px solid var(--border-soft); padding-left: 8px; }
.readonly { margin-left: auto; color: var(--muted); white-space: nowrap; }
.topbar { display: flex; gap: 12px; align-items: center; min-width: 0; }
#current-path { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.menu-toggle { display: none; border: 1px solid var(--border); background: var(--button-bg); color: var(--text); border-radius: 8px; padding: 8px 10px; font-size: 14px; }

@media (max-width: 800px) {
  #app { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    width: min(86vw, 360px);
    z-index: 20;
    box-shadow: 0 0 0 9999px var(--overlay);
  }
  .sidebar.mobile-hidden {
    transform: translateX(-100%);
    box-shadow: none;
  }
  .menu-toggle { display: inline-flex; align-items: center; gap: 8px; }
  .topbar { padding: 10px 12px; gap: 10px; }
  .readonly { display: none; }
  .sidebar-header { position: sticky; top: 0; z-index: 1; }
}