:root {
  --bg: #f8fafc;
  --panel: #ffffff;
  --side: #f1f5f9;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --accent: #4f46e5;
  --accent-weak: #eef2ff;
  --code-bg: #f1f5f9;
  --danger: #ef4444;
  --radius: 12px;
}
[data-theme="dark"] {
  --bg: #0b1220;
  --panel: #111c33;
  --side: #0f1a30;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --border: #1e2f4f;
  --accent: #818cf8;
  --accent-weak: #1e1b4b;
  --code-bg: #0f1a30;
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Pretendard", "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  background: var(--bg);
  color: var(--text);
}
#app { height: 100dvh; display: flex; flex-direction: column; }

.topbar {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 14px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 20;
}
.brand { font-weight: 800; font-size: 17px; white-space: nowrap; }
.brand span { letter-spacing: -0.3px; }
.save-state { font-size: 12px; color: var(--muted); white-space: nowrap; }
.save-state.saving { color: var(--accent); }
.spacer { flex: 1; }
.view-tabs { display: flex; background: var(--side); border: 1px solid var(--border); border-radius: 999px; padding: 2px; }
.view-tabs button { border: 0; background: transparent; color: var(--muted); padding: 6px 10px; border-radius: 999px; font-size: 13px; }
.view-tabs button.active { background: var(--panel); color: var(--text); box-shadow: 0 1px 3px rgba(0,0,0,.15); }

.btn {
  border: 1px solid var(--border); background: var(--panel); color: var(--text);
  padding: 8px 12px; border-radius: 10px; font-size: 14px; cursor: pointer;
}
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 700; }
.btn.small { padding: 6px 10px; font-size: 13px; width: 100%; }
.icon-btn {
  border: 1px solid var(--border); background: var(--panel); color: var(--text);
  width: 36px; height: 36px; border-radius: 10px; cursor: pointer; font-size: 16px;
}
.icon-btn.danger { color: var(--danger); }
.link { background: none; border: 0; color: var(--accent); cursor: pointer; font-size: 13px; }

.layout { flex: 1; display: flex; min-height: 0; }
#sidebar {
  width: 290px; flex-shrink: 0;
  background: var(--side);
  border-right: 1px solid var(--border);
  display: flex; flex-direction: column; min-height: 0;
}
.side-tools { padding: 12px; display: grid; gap: 8px; }
#search {
  width: 100%; padding: 10px 12px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--panel); color: var(--text);
}
#fileList { list-style: none; margin: 0; padding: 0 12px 12px; overflow-y: auto; flex: 1; display: flex; flex-direction: column; gap: 8px; }
#fileList li {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 10px 12px; cursor: pointer;
}
#fileList li.active { border-color: var(--accent); background: var(--accent-weak); }
#fileList .t { font-weight: 700; font-size: 14px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
#fileList .d { font-size: 12px; color: var(--muted); margin-top: 4px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
#fileList .m { font-size: 11px; color: var(--muted); margin-top: 6px; }
.side-foot { padding: 10px 12px; border-top: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; font-size: 12px; color: var(--muted); }

.editor-area { flex: 1; display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.title-row { display: flex; gap: 8px; align-items: center; padding: 12px 14px 6px; }
#titleInput {
  flex: 1; font-size: 20px; font-weight: 800; border: 0; background: transparent; color: var(--text); outline: none; min-width: 0;
}
.meta { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--muted); }

.toolbar {
  display: flex; gap: 4px; align-items: center; flex-wrap: wrap;
  padding: 8px 14px; border-bottom: 1px solid var(--border); background: var(--panel);
}
.toolbar button {
  border: 1px solid transparent; background: transparent; color: var(--text);
  padding: 7px 9px; border-radius: 8px; cursor: pointer; font-size: 13px;
}
.toolbar button:hover { background: var(--side); border-color: var(--border); }
.toolbar .sep { width: 1px; height: 20px; background: var(--border); margin: 0 4px; }

.panes { flex: 1; display: grid; grid-template-columns: 1fr 1fr; min-height: 0; }
.panes[data-view="edit"] { grid-template-columns: 1fr; }
.panes[data-view="edit"] #preview { display: none; }
.panes[data-view="preview"] { grid-template-columns: 1fr; }
.panes[data-view="preview"] #editor { display: none; }
#editor {
  border: 0; resize: none; outline: none; padding: 16px;
  font-size: 15px; line-height: 1.7; font-family: ui-monospace, "SF Mono", "D2Coding", Menlo, Consolas, monospace;
  background: var(--bg); color: var(--text);
  border-right: 1px solid var(--border);
}
#preview { padding: 18px 20px; overflow-y: auto; background: var(--panel); }

.markdown-body { font-size: 15px; line-height: 1.75; word-break: break-word; }
.markdown-body h1, .markdown-body h2, .markdown-body h3 { line-height: 1.3; margin: 1.1em 0 .5em; }
.markdown-body h1 { font-size: 1.7em; border-bottom: 1px solid var(--border); padding-bottom: .3em; }
.markdown-body h2 { font-size: 1.4em; border-bottom: 1px solid var(--border); padding-bottom: .25em; }
.markdown-body pre { background: var(--code-bg); border: 1px solid var(--border); border-radius: 10px; padding: 12px; overflow-x: auto; }
.markdown-body code { background: var(--code-bg); border-radius: 6px; padding: 2px 6px; font-size: .9em; }
.markdown-body pre code { background: transparent; padding: 0; }
.markdown-body blockquote { border-left: 4px solid var(--accent); margin: 12px 0; padding: 4px 12px; color: var(--muted); background: var(--accent-weak); border-radius: 0 8px 8px 0; }
.markdown-body table { border-collapse: collapse; width: 100%; margin: 12px 0; font-size: 14px; }
.markdown-body th, .markdown-body td { border: 1px solid var(--border); padding: 8px; }
.markdown-body th { background: var(--side); }
.markdown-body img { max-width: 100%; border-radius: 10px; }
.markdown-body a { color: var(--accent); }
.markdown-body input[type="checkbox"] { margin-right: 6px; }

.only-mobile { display: none; }
#scrim { position: fixed; inset: 0; background: rgba(0,0,0,.35); z-index: 29; }

/* 동기화 다이얼로그 */
#syncDialog {
  border: 1px solid var(--border); border-radius: 16px;
  background: var(--panel); color: var(--text);
  padding: 20px; width: min(92vw, 440px);
}
#syncDialog::backdrop { background: rgba(0,0,0,.45); }
#syncDialog h3 { margin: 0 0 8px; font-size: 17px; }
#syncDialog label { display: block; font-size: 13px; color: var(--muted); margin: 12px 0 4px; }
#syncDialog input[type="text"], #syncKeyInput, #syncUrlInput {
  width: 100%; padding: 10px 12px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--bg); color: var(--text);
  font-size: 14px; margin-top: 4px;
}
#syncDialog .row { display: flex; gap: 8px; margin-top: 8px; }
#syncDialog .row.gap { margin-top: 12px; }
#syncDialog .row.end { justify-content: flex-end; margin-top: 16px; }
#syncDialog .btn.small { width: auto; white-space: nowrap; }
#syncDialog .check { display: flex; align-items: center; gap: 8px; color: var(--text); }
.dlg-desc { font-size: 13px; color: var(--muted); margin: 0 0 4px; }
.dlg-url { font-size: 12px; color: var(--muted); }
.dlg-url code { font-size: 11px; word-break: break-all; }
.dlg-status { font-size: 13px; margin: 12px 0 0; }
.dlg-status.subtle { color: var(--muted); font-size: 12px; margin-top: 4px; }
.dot { display: inline-block; width: 10px; height: 10px; border-radius: 50%; background: var(--muted); vertical-align: middle; }
.dot.ok { background: #22c55e; }
.dot.busy { background: var(--accent); animation: pulse 1s infinite alternate; }
.dot.err { background: var(--danger); }
@keyframes pulse { from { opacity: .4; } to { opacity: 1; } }

@media (max-width: 860px) {
  .only-mobile { display: inline-flex; align-items: center; justify-content: center; }
  .view-tabs.only-mobile { display: flex; }
  #sidebar {
    position: fixed; left: 0; top: 0; bottom: 0; z-index: 30;
    transform: translateX(-105%); transition: transform .22s ease;
    width: min(84vw, 320px);
  }
  #sidebar.open { transform: none; box-shadow: 0 10px 40px rgba(0,0,0,.3); }
  .brand span { display: none; }
  #btnNew { padding: 8px 10px; }
  .panes { grid-template-columns: 1fr !important; }
  .panes[data-view="split"] { grid-template-rows: 1fr 1fr; grid-template-columns: 1fr !important; }
  .panes[data-view="split"] #editor { border-right: 0; border-bottom: 1px solid var(--border); }
  .panes[data-view="edit"] #preview, .panes[data-view="preview"] #editor { display: none; }
  .panes[data-view="edit"] #editor, .panes[data-view="preview"] #preview { display: block; }
}