:root {
  color-scheme: light;
  --bg: #eef2f6;
  --panel: rgba(255, 255, 255, 0.9);
  --panel-solid: #ffffff;
  --line: #d8dde6;
  --line-strong: #c4ccda;
  --text: #1d2430;
  --muted: #667385;
  --soft: #39485c;
  --accent: #2f5bea;
  --accent-strong: #2449c7;
  --accent-soft: #e4ebff;
  --red: #c43c3c;
  --code-bg: #111827;
  --code-text: #d8e3f0;
  --shadow: 0 18px 48px rgba(31, 41, 55, 0.08);
  --radius: 8px;
  --font-ui: "Segoe UI Variable", "Segoe UI", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  --font-mono: "SFMono-Regular", "Cascadia Mono", "Consolas", monospace;
}

* { box-sizing: border-box; letter-spacing: 0; }
html, body { min-height: 100%; }
body {
  margin: 0;
  color: var(--text);
  background: linear-gradient(180deg, #f7f9fc 0%, #eef2f7 100%);
  font-family: var(--font-ui);
  overflow-x: hidden;
}

body[data-note-mode="txt"] { background: linear-gradient(180deg, #fafbfd 0%, #eef2f7 100%); }
body[data-note-mode="md"] { background: linear-gradient(180deg, #f8fbff 0%, #eef3f8 100%); }
body.preview-focus-mode .sidebar { display: none; }
body.preview-focus-mode .main { padding-left: 16px; padding-right: 16px; }
body.preview-focus-mode .editor-status-bar,
body.preview-focus-mode .toolbar,
body.preview-focus-mode .note-meta,
body.preview-focus-mode .meta-row,
body.preview-focus-mode .quick-strip {
  display: none;
}
body.preview-focus-mode .editor-card { height: calc(100vh - 32px); }
body.is-dragging-split, body.is-dragging-split * { cursor: col-resize !important; user-select: none; }

button, input, textarea { font: inherit; }
button { border: 0; color: inherit; cursor: pointer; }
input, textarea { min-width: 0; border: 0; color: inherit; background: transparent; outline: none; }
input::placeholder, textarea::placeholder { color: #9aa5b6; }

.app-shell { display: grid; grid-template-columns: 248px minmax(0, 1fr); min-height: 100vh; }
.sidebar {
  position: sticky; top: 0; display: flex; flex-direction: column; gap: 10px;
  height: 100vh; padding: 14px 12px; border-right: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72); backdrop-filter: blur(18px); overflow: hidden;
}

.brand, .sidebar-actions, .topbar, .topbar-actions, .sync-grid, .note-item-head, .note-item-meta, .panel-summary, .pane-head, .modal-head, .meta-row, .note-meta, .utility-grid, .editor-status-bar, .pane-actions {
  display: flex; align-items: center;
}
.brand { gap: 10px; }
.brand-mark {
  display: grid; width: 40px; height: 40px; place-items: center; border-radius: var(--radius);
  color: #fff; background: linear-gradient(135deg, #2f5bea, #11a0db);
  box-shadow: 0 12px 28px rgba(47, 91, 234, 0.22); font-family: var(--font-mono); font-weight: 800;
}
.brand h1, .brand p, .topbar h2, .pane-head h3, .modal-head h2, .note-item h3, .utility-grid span, .note-meta { margin: 0; }
.brand h1 { font-size: 16px; line-height: 1.1; }
.brand p { margin-top: 4px; color: var(--muted); font-size: 12px; }

.sidebar-actions, .topbar-actions, .sync-grid, .utility-grid { gap: 8px; }
.sidebar-actions > * { min-width: 0; }
.primary-button, .ghost-button, .danger-button, .icon-button, .text-button, .quick-chip, .toolbar button, .mode-button, .flag-button, .filter-item, .tag-pill, .folder-item, .outline-item {
  min-height: 36px; border-radius: var(--radius); transition: transform 150ms ease, border-color 150ms ease, background 150ms ease, color 150ms ease, box-shadow 150ms ease;
}
.primary-button {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 0 14px; color: #fff;
  background: var(--accent); box-shadow: 0 10px 24px rgba(47, 91, 234, 0.18); font-weight: 700;
}
.primary-button:hover { background: var(--accent-strong); transform: translateY(-1px); }
.ghost-button, .danger-button, .icon-button, .flag-button, .mode-button, .filter-item, .tag-pill, .folder-item, .outline-item, .quick-chip, .toolbar button, .nav-section summary {
  border: 1px solid var(--line); background: rgba(255, 255, 255, 0.92);
}
.ghost-button, .danger-button { padding: 0 13px; font-weight: 650; }
.ghost-button:hover, .icon-button:hover, .flag-button:hover, .mode-button:hover, .quick-chip:hover, .toolbar button:hover, .tag-pill:hover, .folder-item:hover, .outline-item:hover, .filter-item:hover, .nav-section summary:hover {
  border-color: var(--line-strong); background: #fff; transform: translateY(-1px);
}
.danger-button { color: var(--red); background: #fff7f7; }
.icon-button { display: inline-grid; width: 38px; min-width: 38px; place-items: center; font-size: 18px; }
.text-button { min-height: auto; padding: 0; color: var(--accent); background: transparent; font-size: 12px; font-weight: 700; }

.search-box {
  display: grid; grid-template-columns: auto minmax(0, 1fr); align-items: center; gap: 8px; min-height: 40px; padding: 0 12px;
  border: 1px solid var(--line); border-radius: var(--radius); background: #fff; color: var(--muted);
}
.search-box:focus-within { border-color: rgba(47, 91, 234, 0.42); box-shadow: 0 0 0 3px rgba(47, 91, 234, 0.1); }
.search-box input { height: 38px; }

.nav-section {
  border: 1px solid transparent;
  border-radius: var(--radius);
  overflow: hidden;
}
.nav-section[open] { border-color: var(--line); background: rgba(255,255,255,0.5); }
.nav-section > * + * { padding: 0 0 10px; }
.panel-summary {
  justify-content: space-between; gap: 12px; min-height: 34px; padding: 0 10px;
  list-style: none; cursor: pointer; user-select: none; font-size: 13px; font-weight: 700; color: var(--soft);
}
.panel-summary::-webkit-details-marker { display: none; }

.filter-list, .folder-list, .outline-list, .note-list { display: grid; gap: 8px; min-height: 0; }
.filter-item, .folder-item, .outline-item {
  display: flex; align-items: center; justify-content: space-between; width: 100%; padding: 0 12px; color: var(--soft); text-align: left;
}
.filter-item strong, .folder-item strong {
  display: grid; min-width: 26px; height: 24px; place-items: center; border-radius: 999px; color: var(--muted); background: #eff3f8; font-size: 12px;
}
.filter-item.active, .filter-item.active strong, .tag-pill.active, .folder-item.active, .outline-item.active, .quick-chip.active, .mode-button.active, .flag-button.active {
  border-color: rgba(47, 91, 234, 0.34); color: var(--accent); background: var(--accent-soft);
}

.note-list-panel { flex: 1; display: flex; flex-direction: column; gap: 10px; min-height: 0; }
.tag-list { display: flex; flex-wrap: wrap; gap: 7px; }
.tag-pill { min-height: 28px; padding: 0 10px; color: var(--soft); font-size: 12px; }
.note-list { overflow: auto; padding-right: 2px; }
.note-list::-webkit-scrollbar, textarea::-webkit-scrollbar, .preview-content::-webkit-scrollbar, .outline-list::-webkit-scrollbar { width: 10px; }
.note-list::-webkit-scrollbar-thumb, textarea::-webkit-scrollbar-thumb, .preview-content::-webkit-scrollbar-thumb, .outline-list::-webkit-scrollbar-thumb {
  border: 3px solid transparent; border-radius: 999px; background: rgba(102, 115, 133, 0.42); background-clip: padding-box;
}
.note-item {
  display: grid; gap: 7px; padding: 12px; border: 1px solid var(--line); border-radius: var(--radius);
  background: rgba(255,255,255,0.82); text-align: left;
}
.note-item:hover, .note-item.active { border-color: rgba(47, 91, 234, 0.32); background: #fff; box-shadow: 0 10px 26px rgba(31, 41, 55, 0.06); }
.note-item-head { justify-content: space-between; gap: 10px; }
.note-item h3 { overflow: hidden; font-size: 14px; text-overflow: ellipsis; white-space: nowrap; }
.note-item p { display: -webkit-box; margin: 0; overflow: hidden; color: var(--muted); font-size: 12px; line-height: 1.45; -webkit-box-orient: vertical; -webkit-line-clamp: 2; }
.note-item-meta { justify-content: space-between; gap: 10px; color: var(--muted); font-size: 11px; }
.note-item-tags { display: flex; align-items: center; gap: 5px; min-width: 0; overflow: hidden; }
.note-item-tags em { padding: 2px 6px; border-radius: 999px; background: #eef3ff; color: var(--accent); font-style: normal; }
.note-item-tags span { max-width: 72px; overflow: hidden; padding: 3px 7px; border-radius: 999px; background: #eff3f8; text-overflow: ellipsis; white-space: nowrap; }

.main { display: flex; min-width: 0; flex-direction: column; gap: 10px; padding: 12px 12px 14px; }
.topbar { justify-content: space-between; gap: 16px; }
.topbar h2 { margin-top: 4px; font-size: 18px; line-height: 1.15; }
.eyebrow { color: var(--accent); font-size: 12px; font-weight: 760; }
.quick-strip { display: flex; gap: 8px; overflow-x: auto; padding: 0 0 2px; }
.quick-chip { flex: 0 0 auto; padding: 0 12px; color: var(--soft); font-size: 13px; font-weight: 650; }

.editor-card {
  display: flex; flex-direction: column; min-width: 0; min-height: 0;
  height: calc(100vh - 112px); border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--panel); box-shadow: var(--shadow); overflow: hidden;
}
.note-meta { justify-content: space-between; gap: 12px; padding: 14px 14px 8px; }
.title-input { width: 100%; height: 42px; font-size: 21px; font-weight: 760; font-family: var(--font-ui); }
.note-flags { display: flex; gap: 8px; }
.flag-button, .mode-button { display: inline-flex; align-items: center; justify-content: center; padding: 0 12px; font-weight: 700; }
.meta-row { gap: 8px; padding: 0 14px 10px; }
.segmented { display: inline-flex; gap: 6px; padding: 4px; border: 1px solid var(--line); border-radius: calc(var(--radius) + 2px); background: rgba(255,255,255,0.78); }
.mode-button { min-width: 56px; }
.folder-input, .tags-input { height: 34px; padding: 0 12px; border: 1px solid var(--line); border-radius: var(--radius); background: rgba(255,255,255,0.84); }
.folder-input { flex: 0 0 160px; }
.tags-input { flex: 1; }
.toolbar {
  display: flex; flex-wrap: wrap; gap: 7px; padding: 8px 14px;
  border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: rgba(249, 251, 253, 0.96);
}
.toolbar button { min-width: 36px; padding: 0 10px; color: var(--soft); font-weight: 700; }
.toolbar-separator { width: 1px; margin: 4px 2px; background: var(--line); }
.editor-card[data-mode="txt"] .md-tool, .editor-card[data-mode="txt"] [data-insert], .editor-card[data-mode="txt"] #togglePreviewButton, .editor-card[data-mode="txt"] #previewFocusButton { display: none; }
.editor-status-bar {
  justify-content: space-between; gap: 12px; padding: 9px 14px;
  border-bottom: 1px solid var(--line); color: var(--muted); background: rgba(255,255,255,0.72); font-size: 12px;
}

.split-editor {
  --split-ratio: 58%;
  display: grid;
  grid-template-columns: minmax(0, var(--split-ratio)) 12px minmax(0, calc(100% - var(--split-ratio) - 12px));
  min-height: 0;
  flex: 1;
}
.split-editor.preview-hidden { grid-template-columns: minmax(0, 1fr); }
.split-editor.preview-focus { grid-template-columns: minmax(0, 1fr); }
.split-editor.preview-focus .splitter { display: none; }
.split-editor.preview-focus .write-pane { display: none; }
.write-pane, .preview-pane { display: flex; min-width: 0; min-height: 0; flex-direction: column; }
.write-pane { border-right: 1px solid var(--line); }
.pane-head {
  justify-content: space-between; gap: 10px; min-height: 40px; padding: 0 14px; border-bottom: 1px solid var(--line); background: rgba(255,255,255,0.72);
}
.pane-head h3 { color: var(--soft); font-size: 13px; }
.pane-actions { gap: 8px; color: var(--muted); font-size: 12px; }
.pane-actions .icon-button { width: 32px; min-width: 32px; height: 32px; }
.splitter {
  background: linear-gradient(180deg, rgba(216, 221, 230, 0.6), rgba(196, 204, 218, 0.6));
  cursor: col-resize;
}
.splitter:hover { background: linear-gradient(180deg, rgba(47,91,234,0.3), rgba(47,91,234,0.2)); }
.text-shell {
  display: grid; grid-template-columns: 52px minmax(0, 1fr); min-height: 0; flex: 1;
  background: linear-gradient(180deg, rgba(250,251,253,0.92), rgba(245,248,252,0.96));
}
.line-numbers {
  overflow: hidden; padding: 14px 10px 14px 0; border-right: 1px solid var(--line); color: #8a95a5; background: rgba(244,247,250,0.96);
  font-family: var(--font-mono); font-size: 12px; line-height: 1.68; text-align: right; white-space: nowrap; user-select: none;
}
#bodyInput { width: 100%; min-height: 0; resize: none; padding: 14px 16px 18px; background: transparent; font-size: 14px; line-height: 1.7; font-family: var(--font-mono); }
.preview-pane { background: linear-gradient(180deg, #ffffff 0%, #fbfcfe 100%); }
.preview-content {
  min-height: 0; flex: 1; overflow: auto; padding: 18px 22px 36px; line-height: 1.8; color: #1f2937; font-family: var(--font-ui);
}
.preview-content h1, .preview-content h2, .preview-content h3, .preview-content h4 { margin: 1em 0 0.45em; line-height: 1.3; }
.preview-content h1:first-child, .preview-content h2:first-child, .preview-content h3:first-child, .preview-content h4:first-child, .preview-content p:first-child, .preview-content pre:first-child, .preview-content table:first-child { margin-top: 0; }
.preview-content h1 { font-size: 28px; }
.preview-content h2 { padding-bottom: 7px; border-bottom: 1px solid #e5eaf3; font-size: 21px; }
.preview-content h3 { font-size: 17px; }
.preview-content h4 { font-size: 15px; }
.preview-content p, .preview-content ul, .preview-content ol, .preview-content blockquote, .preview-content pre, .preview-content .code-card { margin: 0.8em 0; }
.preview-content a { color: var(--accent); }
.preview-content code { padding: 2px 6px; border-radius: 6px; background: #eef3ff; color: #2342a6; font-family: var(--font-mono); font-size: 0.92em; }
.code-card { overflow: hidden; border: 1px solid #dbe2ef; border-radius: var(--radius); background: var(--code-bg); }
.code-head {
  display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 10px 12px; border-bottom: 1px solid rgba(255,255,255,0.08); color: #98a6b8; font-size: 12px;
}
.code-head button {
  min-height: 28px; padding: 0 10px; border: 1px solid rgba(255,255,255,0.14); border-radius: 6px; background: rgba(255,255,255,0.06); color: #e7eef7;
}
.preview-content pre { overflow: auto; margin: 0; padding: 14px; color: var(--code-text); font-family: var(--font-mono); }
.preview-content pre code { padding: 0; background: transparent; color: inherit; }
.preview-content blockquote { padding: 10px 14px; border-left: 4px solid var(--accent); border-radius: 0 var(--radius) var(--radius) 0; background: #f4f7ff; color: #41516a; }
.preview-content table { width: 100%; border-collapse: collapse; margin: 1em 0; font-size: 14px; }
.preview-content th, .preview-content td { padding: 8px 10px; border: 1px solid #dde4ef; }
.preview-content th { background: #f7f9fd; }
.preview-content .task { list-style: none; margin-left: -1.4em; }
.preview-hidden .preview-pane { display: none; }
.preview-focus .write-pane { display: none; }

.utility-drawer { border: 1px solid var(--line); border-radius: var(--radius); background: rgba(255,255,255,0.74); box-shadow: 0 12px 30px rgba(31,41,55,0.05); }
.utility-drawer > summary { list-style: none; padding: 10px 14px; color: var(--soft); font-weight: 650; cursor: pointer; }
.utility-drawer > summary::-webkit-details-marker { display: none; }
.utility-grid { flex-wrap: wrap; gap: 8px 10px; padding: 0 14px 12px; border-top: 1px solid var(--line); }
.utility-grid span { color: var(--muted); font-size: 12px; }

.modal { width: min(560px, calc(100vw - 32px)); border: 0; padding: 0; background: transparent; }
.modal::backdrop { background: rgba(17,24,39,0.34); backdrop-filter: blur(4px); }
.modal-card { display: grid; gap: 14px; padding: 18px; border: 1px solid var(--line); border-radius: 10px; background: #fff; box-shadow: var(--shadow); }
.modal-head { justify-content: space-between; gap: 16px; }
.modal-copy { margin: 0; color: var(--soft); line-height: 1.65; }
.field, .toggle-field { display: grid; gap: 7px; color: var(--soft); font-weight: 650; }
.field input { height: 42px; padding: 0 12px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; font-weight: 400; }
.field input:focus { border-color: rgba(47,91,234,0.42); box-shadow: 0 0 0 3px rgba(47,91,234,0.1); }
.toggle-field { grid-template-columns: auto minmax(0, 1fr); align-items: center; padding: 10px 12px; border: 1px solid var(--line); border-radius: var(--radius); background: #fbfcfe; }
.toggle-field input { width: 16px; height: 16px; }
.sync-grid button { flex: 1; }
.sync-message { padding: 11px 12px; border: 1px solid var(--line); border-radius: var(--radius); background: #f7f9fc; color: var(--soft); font-size: 13px; }
.toast {
  position: fixed; right: 18px; bottom: 18px; z-index: 20; max-width: min(360px, calc(100vw - 36px)); padding: 11px 13px;
  border: 1px solid var(--line); border-radius: var(--radius); background: rgba(255,255,255,0.96); box-shadow: var(--shadow); color: var(--soft);
  opacity: 0; pointer-events: none; transform: translateY(8px); transition: opacity 180ms ease, transform 180ms ease;
}
.toast.show { opacity: 1; transform: translateY(0); }
.empty-state { padding: 16px 12px; border: 1px dashed var(--line-strong); border-radius: var(--radius); color: var(--muted); background: rgba(255,255,255,0.48); text-align: center; }
.empty-state.compact { padding: 10px 10px; }

@media (max-width: 1320px) {
  .app-shell { grid-template-columns: 236px minmax(0, 1fr); }
  .editor-card { height: 720px; }
}

@media (max-width: 1020px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar { position: static; height: auto; overflow: visible; }
  .main { padding: 12px; }
  .topbar, .topbar-actions { align-items: stretch; flex-direction: column; }
  .topbar-actions { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .editor-card { height: auto; min-height: 0; }
  .meta-row { flex-wrap: wrap; }
  .folder-input { flex: 1 1 220px; }
}

@media (max-width: 560px) {
  .sidebar, .main { padding: 10px; }
  .title-input { font-size: 20px; }
  .topbar-actions, .sync-grid { grid-template-columns: 1fr; }
  .toolbar { padding: 8px 12px; }
  .note-meta { align-items: flex-start; flex-direction: column; }
}