:root{color-scheme:light;--border: #d9d9d9;--bg: #fafafa;--bg-raised: #ffffff;--text: #1a1a1a;--text-muted: #666666;--accent: #4a5568}:root[data-theme=dark]{color-scheme:dark;--border: #3f3f3f;--bg: #1e1e1e;--bg-raised: #282828;--text: #e6e6e6;--text-muted: #9a9a9a;--accent: #8b9bb4}*{box-sizing:border-box}html,body,#root{height:100%;margin:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Hiragino Sans,Noto Sans JP,sans-serif;background:var(--bg-raised);color:var(--text)}.app{display:flex;flex-direction:column;height:100%}.toolbar{display:flex;align-items:center;gap:1rem;padding:0 1rem;height:48px;border-bottom:1px solid var(--border);background:var(--bg);flex:none}.toolbar-brand{font-size:1rem;font-weight:700;margin:0}.toolbar-theme{display:flex;align-items:center;gap:.5rem;font-size:.85rem}.toolbar-theme select{font-size:.85rem;padding:.25rem .5rem}.toolbar-actions{margin-left:auto;display:flex;gap:.5rem}.toolbar-actions button{font-size:.85rem;padding:.35rem .75rem;border:1px solid var(--border);border-radius:6px;background:var(--bg-raised);color:var(--text);cursor:pointer}.toolbar-actions .icon-button{width:2.1rem;padding:.35rem 0;line-height:1}.toolbar-actions button:hover{border-color:var(--accent)}.settings-backdrop{position:fixed;inset:0;z-index:10;display:grid;place-items:start end;padding:3.5rem 1rem 1rem;background:#0000003d}.settings-dialog{width:min(22rem,calc(100vw - 2rem));padding:1rem;border:1px solid var(--border);border-radius:8px;background:var(--bg-raised);box-shadow:0 18px 48px #00000038}.settings-header{display:flex;align-items:center;justify-content:space-between;gap:1rem;margin-bottom:1rem}.settings-header h2{margin:0;font-size:1rem}.settings-header .icon-button{width:2rem;height:2rem;padding:0}.settings-field{display:grid;gap:.45rem;margin:0 0 1rem;padding:0;border:0;font-size:.9rem}.settings-field:last-child{margin-bottom:0}.settings-field select{font-size:.95rem;padding:.45rem .55rem;border:1px solid var(--border);border-radius:6px;background:var(--bg);color:var(--text)}.settings-field legend{padding:0;color:var(--text)}.segmented-control{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--border);border-radius:6px;overflow:hidden}.segmented-control button{min-height:2.25rem;border:0;border-right:1px solid var(--border);background:var(--bg);color:var(--text-muted);cursor:pointer}.segmented-control button:last-child{border-right:0}.segmented-control button.active{background:var(--accent);color:var(--bg-raised);font-weight:600}.panes{display:flex;flex:1;min-height:0}.editor-pane{display:flex;flex-direction:column;width:50%;min-width:0;border-right:1px solid var(--border)}.editor-tabs{display:flex;flex:none;border-bottom:1px solid var(--border);background:var(--bg)}.editor-tab{padding:.4rem 1.25rem;font-size:.85rem;border:none;border-bottom:2px solid transparent;background:none;cursor:pointer;color:var(--text-muted)}.editor-tab.active{color:var(--text);border-bottom-color:var(--accent);font-weight:600}.editor-body{flex:1;min-height:0;overflow:hidden}.editor-body[hidden]{display:none}.editor-body>div{height:100%}.editor-body .cm-editor{height:100%;font-size:14px}.preview-frame{width:50%;height:100%;border:none;background:#fff}