:root {
  --bg: #0f1115;
  --panel: #161a21;
  --line: #262c36;
  --text: #e6e9ef;
  --muted: #8b93a3;
  --accent: #5ac8c8;
  --row: 30px;
  color-scheme: dark;
  font: 14px/1.4 system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; height: 100vh; display: flex; flex-direction: column; background: var(--bg); color: var(--text); }

header {
  display: flex; align-items: center; gap: 12px; padding: 10px 16px;
  border-bottom: 1px solid var(--line); background: var(--panel);
}
.brand { font-weight: 600; letter-spacing: .02em; margin-right: 8px; }
label { color: var(--muted); display: flex; align-items: center; gap: 6px; }
select, input[type=search] {
  background: var(--bg); color: var(--text); border: 1px solid var(--line);
  border-radius: 6px; padding: 5px 8px; font: inherit;
}
input[type=search] { flex: 1; max-width: 420px; }
.status { color: var(--muted); margin-left: auto; white-space: nowrap; font-size: 13px; }
.status.error { color: #ff7b72; }

main { flex: 1; min-height: 0; display: grid; grid-template-columns: 260px 1fr 380px; }

#sidebar { overflow: auto; border-right: 1px solid var(--line); padding: 6px 0; }
.node { display: block; padding: 2px 8px; cursor: pointer; white-space: nowrap; color: var(--text); text-decoration: none; }
.node:hover { background: #1c2129; }
.node.current { color: var(--accent); }
.node .twist { display: inline-block; width: 14px; color: var(--muted); }
.children { margin-left: 12px; }

#listing { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.crumbs { padding: 8px 12px; border-bottom: 1px solid var(--line); white-space: nowrap; overflow-x: auto; }
.crumbs a { color: var(--accent); text-decoration: none; cursor: pointer; }
.crumbs span { color: var(--muted); margin: 0 4px; }
.columns, .row { display: grid; grid-template-columns: 1fr 100px 160px; gap: 12px; padding: 0 12px; }
.columns { color: var(--muted); font-size: 12px; padding-top: 6px; padding-bottom: 6px; border-bottom: 1px solid var(--line); }
.rows { flex: 1; overflow: auto; position: relative; outline: none; }
#spacer { position: relative; }
.row { position: absolute; left: 0; right: 0; height: var(--row); align-items: center; cursor: pointer; }
.row:hover { background: #1c2129; }
.row.selected { background: #1f2a33; }
.row .name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.row .name.dir::before { content: "📁 "; }
.row .name.file::before { content: "📄 "; }
.row .size, .row .type { color: var(--muted); font-size: 12px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.row .size { text-align: right; }

.preview { border-left: 1px solid var(--line); overflow: auto; padding: 14px; display: flex; flex-direction: column; gap: 10px; }
.preview.empty { align-items: center; justify-content: center; }
.hint { color: var(--muted); }
.preview h2 { font-size: 15px; margin: 0; word-break: break-all; }
.preview dl { display: grid; grid-template-columns: auto 1fr; gap: 4px 10px; margin: 0; font-size: 12px; }
.preview dt { color: var(--muted); }
.preview dd { margin: 0; word-break: break-all; }
.preview .actions { display: flex; gap: 8px; flex-wrap: wrap; }
.preview button, .preview a.button {
  background: #1f2a33; color: var(--text); border: 1px solid var(--line); border-radius: 6px;
  padding: 5px 10px; font: inherit; cursor: pointer; text-decoration: none;
}
.preview button:hover, .preview a.button:hover { border-color: var(--accent); }
.preview img, .preview video { max-width: 100%; border-radius: 6px; background:
  repeating-conic-gradient(#20252e 0 25%, #181c23 0 50%) 0 0 / 16px 16px; }
.preview audio { width: 100%; }
.preview pre {
  margin: 0; padding: 10px; background: var(--panel); border: 1px solid var(--line); border-radius: 6px;
  font: 12px/1.45 ui-monospace, "Cascadia Code", Consolas, monospace; white-space: pre-wrap; word-break: break-all;
  max-height: 60vh; overflow: auto;
}

@media (max-width: 900px) {
  main { grid-template-columns: 1fr; grid-template-rows: 1fr auto; }
  #sidebar { display: none; }
  .preview { border-left: 0; border-top: 1px solid var(--line); max-height: 45vh; }
}