/* ================= 基础 ================= */
:root {
  --bg: #f5f6f8;
  --panel: #ffffff;
  --border: #e3e6ea;
  --text: #24292f;
  --muted: #6b7280;
  --accent: #2f6bff;
  --accent-weak: #eaf0ff;
  --danger: #d9534f;
  --radius: 6px;
  --topbar-h: 52px;
  --toolbar-h: 42px;
  --status-h: 28px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body { height: 100%; }

body {
  font-family: -apple-system, "Segoe UI", "Microsoft YaHei", "PingFang SC", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--panel);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

button { font-family: inherit; cursor: pointer; }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: #cdd2d9; border-radius: 5px; border: 2px solid transparent; background-clip: content-box; }
::-webkit-scrollbar-thumb:hover { background: #aab1ba; background-clip: content-box; }
::-webkit-scrollbar-track { background: transparent; }

/* ================= 顶栏 ================= */
.topbar {
  height: var(--topbar-h);
  flex: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 0 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

.brand { display: flex; align-items: center; gap: 10px; min-width: 0; }

.logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: linear-gradient(135deg, #2f6bff, #7a3cff);
  color: #fff;
  font-weight: 700;
  font-size: 14px;
  letter-spacing: -1px;
  flex: none;
}

.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 15px; }
.brand-text small { color: var(--muted); font-size: 11px; }

.top-actions { display: flex; align-items: center; gap: 6px; flex-wrap: nowrap; }

.tb-btn {
  height: 30px;
  padding: 0 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--panel);
  color: var(--text);
  font-size: 13px;
  white-space: nowrap;
  transition: background .15s, border-color .15s, color .15s;
}
.tb-btn:hover { background: var(--accent-weak); border-color: #bcd0ff; color: var(--accent); }
.tb-btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.tb-btn.primary:hover { background: #245be0; border-color: #245be0; color: #fff; }
.tb-btn.toggle.active { background: var(--accent-weak); border-color: #bcd0ff; color: var(--accent); }

.v-divider { width: 1px; height: 18px; background: var(--border); margin: 0 4px; flex: none; }

.seg {
  display: flex;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.seg button {
  height: 30px;
  padding: 0 12px;
  border: none;
  background: var(--panel);
  font-size: 13px;
  color: var(--muted);
  border-left: 1px solid var(--border);
}
.seg button:first-child { border-left: none; }
.seg button.active { background: var(--accent); color: #fff; }

/* ================= 工具栏 ================= */
.toolbar {
  height: var(--toolbar-h);
  flex: none;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0 12px;
  border-bottom: 1px solid var(--border);
  background: #fafbfc;
  overflow-x: auto;
  overflow-y: hidden;
}

.tool-group { display: flex; align-items: center; gap: 4px; }

.tool-btn {
  height: 28px;
  min-width: 30px;
  padding: 0 8px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  background: transparent;
  color: var(--text);
  font-size: 12.5px;
  white-space: nowrap;
}
.tool-btn:hover { background: #eef1f5; border-color: var(--border); }
.tool-btn:disabled { opacity: .45; cursor: default; }
.tool-btn:disabled:hover { background: transparent; border-color: transparent; }
.tool-btn.bold { font-weight: 700; }
.tool-btn.italic { font-style: italic; font-family: Georgia, serif; }
.tool-btn.strike { text-decoration: line-through; }

/* ================= 主区域 ================= */
.layout { flex: 1; display: flex; min-height: 0; }

.editor-pane { flex: 1; min-width: 0; display: flex; border-right: 1px solid var(--border); }

#editor {
  flex: 1;
  width: 100%;
  border: none;
  outline: none;
  resize: none;
  padding: 20px 22px;
  font-family: "Cascadia Code", Consolas, "JetBrains Mono", "Microsoft YaHei", monospace;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text);
  background: var(--panel);
  caret-color: var(--accent);
}

.preview-pane { flex: 1; min-width: 0; display: flex; }

.preview-wrap {
  flex: 1;
  overflow: auto;
  background: var(--bg);
  padding: 26px 24px 48px;
}

/* A4 纸张 */
.paper {
  width: min(210mm, 100%);
  min-height: 297mm;
  margin: 0 auto;
  padding: 22mm 19mm;
  background: #fff;
  box-shadow: 0 2px 14px rgba(20, 30, 60, .13);
  border-radius: 2px;
}

/* 视图模式 */
body[data-mode="mode-edit"] .preview-pane { display: none; }
body[data-mode="mode-edit"] .editor-pane { border-right: none; }
body[data-mode="mode-preview"] .editor-pane { display: none; }

/* ================= 状态栏 ================= */
.statusbar {
  height: var(--status-h);
  flex: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 14px;
  border-top: 1px solid var(--border);
  background: #fafbfc;
  font-size: 12px;
  color: var(--muted);
}
.statusbar .sep { color: var(--border); }
.statusbar .flex1 { flex: 1; }
#st-save.ok { color: #1a9e55; }
#st-save.editing { color: #d98a1f; }

/* ================= 预览内容排版（导出 HTML 复用同名规则） ================= */
.paper { line-height: 1.75; font-size: 15px; word-wrap: break-word; }
.paper > *:first-child { margin-top: 0 !important; }
.paper > *:last-child { margin-bottom: 0 !important; }

.paper h1, .paper h2, .paper h3, .paper h4, .paper h5, .paper h6 {
  margin: 1.4em 0 .7em;
  font-weight: 600;
  line-height: 1.35;
}
.paper h1 { font-size: 1.9em; padding-bottom: .3em; border-bottom: 1px solid var(--border); }
.paper h2 { font-size: 1.5em; padding-bottom: .3em; border-bottom: 1px solid #eef0f3; }
.paper h3 { font-size: 1.25em; }
.paper h4 { font-size: 1.1em; }
.paper h5 { font-size: 1em; }
.paper h6 { font-size: .95em; color: var(--muted); }

.paper p { margin: .8em 0; }
.paper a { color: var(--accent); text-decoration: none; }
.paper a:hover { text-decoration: underline; }

.paper strong { font-weight: 600; }
.paper del { color: var(--muted); }

.paper ul, .paper ol { margin: .8em 0; padding-left: 2em; }
.paper li { margin: .3em 0; }
.paper li > p { margin: .3em 0; }
.paper li::marker { color: #9aa4b2; }

.paper li.task-list-item { list-style: none; margin-left: -1.6em; }
.paper li.task-list-item input { margin-right: .45em; vertical-align: -2px; }

.paper blockquote {
  margin: 1em 0;
  padding: .35em 1.1em;
  color: #4b5563;
  border-left: 4px solid #c9d4e8;
  background: #f7f9fc;
  border-radius: 0 4px 4px 0;
}

.paper code {
  font-family: "Cascadia Code", Consolas, "Microsoft YaHei", monospace;
  font-size: .875em;
  background: #f0f2f5;
  border: 1px solid #e6e9ee;
  border-radius: 4px;
  padding: .12em .4em;
}

.paper pre {
  margin: 1em 0;
  padding: 14px 16px;
  background: #f6f8fa;
  border: 1px solid #e6e9ee;
  border-radius: 8px;
  overflow-x: auto;
}
.paper pre code {
  display: block;
  background: none;
  border: none;
  padding: 0;
  font-size: .85em;
  line-height: 1.65;
}

.paper table {
  margin: 1em 0;
  border-collapse: collapse;
  width: 100%;
  font-size: .95em;
  display: table;
}
.paper th, .paper td { border: 1px solid #dfe3e8; padding: 7px 12px; text-align: left; }
.paper th { background: #f6f8fa; font-weight: 600; }
.paper tr:nth-child(2n) td { background: #fbfcfd; }

.paper hr {
  margin: 1.6em 0;
  border: none;
  border-top: 1px solid var(--border);
}

.paper img { max-width: 100%; border-radius: 4px; }

.paper kbd {
  display: inline-block;
  padding: 1px 6px;
  font-size: .82em;
  font-family: Consolas, monospace;
  border: 1px solid #cbd2da;
  border-bottom-width: 2px;
  border-radius: 4px;
  background: #fafbfc;
}

/* ================= 弹窗 ================= */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, .45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}
.modal-overlay[hidden] { display: none; }

.modal {
  width: min(420px, calc(100vw - 40px));
  max-height: 80vh;
  overflow: auto;
  background: var(--panel);
  border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, .25);
  padding: 18px 20px;
}
.modal-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.modal-head strong { font-size: 15px; }
.modal-close {
  width: 26px; height: 26px;
  border: none; border-radius: 6px;
  background: transparent; color: var(--muted);
  font-size: 18px; line-height: 1;
}
.modal-close:hover { background: #eef1f5; color: var(--text); }

.shortcut-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.shortcut-table td { padding: 6px 4px; border-bottom: 1px solid #f0f2f5; }
.shortcut-table td:first-child { width: 46%; white-space: nowrap; }
kbd {
  display: inline-block;
  padding: 1px 6px;
  font-size: 11.5px;
  font-family: Consolas, monospace;
  color: var(--text);
  border: 1px solid #cbd2da;
  border-bottom-width: 2px;
  border-radius: 4px;
  background: #f6f8fa;
  margin: 0 1px;
}

/* ================= 打印 / 导出 PDF ================= */
@media print {
  @page { size: A4; margin: 20mm 18mm; }

  body { overflow: visible; background: #fff; }
  .topbar, .toolbar, .statusbar, .editor-pane, .modal-overlay { display: none !important; }

  .layout { display: block; }
  .preview-pane { display: flex !important; }
  .preview-wrap { overflow: visible !important; background: none !important; padding: 0 !important; }

  .paper {
    width: auto !important;
    min-height: 0 !important;
    margin: 0 !important;
    padding: 0 !important;
    box-shadow: none !important;
    border-radius: 0 !important;
    font-size: 12pt;
  }

  .paper h1, .paper h2, .paper h3, .paper h4 { break-after: avoid; page-break-after: avoid; }
  .paper pre, .paper blockquote, .paper table, .paper img, .paper li { break-inside: avoid; page-break-inside: avoid; }
  .paper a { color: #2f56c4; }
}