:root {
  color-scheme: light dark;
  font: 15px/1.5 system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --bg: light-dark(#f5f6f8, #17191c);
  --panel: light-dark(#fff, #202328);
  --border: light-dark(#d9dde3, #353a42);
  --text: light-dark(#20242a, #edf0f3);
  --muted: light-dark(#68717d, #aab3bd);
  --accent: #3578e5;
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; grid-template-rows: auto 1fr auto; color: var(--text); background: var(--bg); }
button, input { font: inherit; }
button, .button { border: 1px solid var(--border); border-radius: 7px; background: var(--panel); color: var(--text); padding: .5rem .75rem; cursor: pointer; text-decoration: none; }
button:hover, .button:hover { border-color: var(--accent); }
.app-header { padding: 1rem 1.25rem; border-bottom: 1px solid var(--border); background: var(--panel); display: flex; align-items: flex-start; justify-content: space-between; gap: 2rem; }
h1, h2, p { margin: 0; }
h1 { font-size: 1.15rem; }
.app-header p, .meta, footer { color: var(--muted); font-size: .82rem; }
.brand { flex: 0 0 auto; padding-top: .15rem; }
.toolbar { display: grid; gap: .55rem; width: min(100%, 48rem); }
.primary-actions, .actions { display: flex; align-items: center; gap: .5rem; flex-wrap: wrap; }
.search input { width: 13rem; border: 1px solid var(--border); border-radius: 7px; padding: .52rem .7rem; color: var(--text); background: var(--bg); }
.url-form { display: flex; gap: .35rem; flex: 1 1 22rem; min-width: 18rem; }
.url-form input { min-width: 10rem; flex: 1; border: 1px solid var(--border); border-radius: 7px; padding: .52rem .7rem; color: var(--text); background: var(--bg); }
.workspace { min-height: 0; display: grid; grid-template-columns: minmax(15rem, 22rem) 1fr; }
.sidebar { min-height: 0; overflow: auto; border-right: 1px solid var(--border); background: var(--panel); }
.sidebar-heading { position: sticky; top: 0; z-index: 1; display: flex; justify-content: space-between; padding: .8rem 1rem; border-bottom: 1px solid var(--border); background: var(--panel); }
.sidebar-filter { display: block; padding: .65rem .75rem .35rem; background: var(--panel); }
.sidebar-filter input { width: 100%; border: 1px solid var(--border); border-radius: 7px; padding: .52rem .7rem; color: var(--text); background: var(--bg); }
.quiet { border: 0; padding: 0; color: var(--muted); background: transparent; }
.file-list { padding: .35rem; }
.file-row { width: 100%; display: flex; align-items: center; gap: .55rem; padding: .5rem .65rem; text-align: left; border: 0; border-radius: 6px; background: transparent; cursor: pointer; }
.file-row:hover { background: color-mix(in srgb, var(--accent) 8%, transparent); }
.file-row.selected { color: var(--accent); background: color-mix(in srgb, var(--accent) 15%, transparent); }
.file-icon { flex: 0 0 1.4rem; text-align: center; }
.file-name { min-width: 0; flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-remove { flex: 0 0 auto; border: 0; padding: 0 .2rem; color: var(--muted); background: transparent; font-size: 1.1rem; line-height: 1; }
.file-remove:hover { color: #d44; border-color: transparent; }
.preview { min-width: 0; overflow: auto; }
.preview-header { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1rem 1.35rem; border-bottom: 1px solid var(--border); background: var(--panel); }
.preview-header h2 { font-size: 1.05rem; overflow-wrap: anywhere; }
.preview-body { padding: 1.35rem; }
.code { margin: 0; padding: 1rem; overflow: auto; border: 1px solid var(--border); border-radius: 7px; background: var(--panel); white-space: pre-wrap; overflow-wrap: anywhere; }
.preview-body table { width: 100%; border-collapse: collapse; background: var(--panel); }
th, td { padding: .45rem .6rem; border: 1px solid var(--border); text-align: left; vertical-align: top; }
.markdown-content { max-width: 60rem; margin: auto; padding: 1rem; background: var(--panel); }
.markdown-content img { max-width: 100%; }
.media-preview { display: block; max-width: 100%; max-height: 75vh; margin: auto; }
.media-player { width: min(100%, 55rem); display: block; margin: 3rem auto; }
.document-frame { width: 100%; height: 75vh; border: 1px solid var(--border); background: white; }
.empty-state { display: grid; gap: .25rem; padding: 2rem 1rem; color: var(--muted); text-align: center; }
.empty-state.large { min-height: 50vh; place-content: center; }
.empty-state strong { color: var(--text); }
.error { color: #d44; }
footer { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: .5rem 1rem; border-top: 1px solid var(--border); background: var(--panel); }
footer a { color: var(--accent); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); }
@media (max-width: 700px) {
  .app-header { flex-direction: column; gap: 1rem; }
  .brand, .toolbar { width: 100%; }
  .primary-actions button { flex: 1; }
  .url-form { width: 100%; }
  .url-form { min-width: 0; }
  .workspace { grid-template-columns: 1fr; grid-template-rows: minmax(10rem, 35vh) 1fr; }
  .sidebar { border-right: 0; border-bottom: 1px solid var(--border); }
}