/* ── 基础（Apple 极简 + 低对比度） ─────────────────────────────── */
* { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --canvas: #ffffff;
  --sidebar: #f5f5f7;        /* 浅灰侧栏 */
  --parchment: #f5f5f7;
  --ink: #3d3d3f;            /* 柔和正文 */
  --ink-strong: #2c2c2e;     /* 标题 */
  --muted: #8e8e93;
  --border: rgba(0,0,0,.07);
  --hairline: #e8e8ed;
  --blue: #0066cc;           /* Action Blue —— 唯一强调色 */
  --blue-focus: #0071e3;
  --sky-blue: #2997ff;
  --danger: #dc2626;
  --radius-pill: 9999px;
  --radius-xs: 5px;
  --radius-sm: 8px;
  --radius-md: 11px;
  --radius-lg: 18px;
  --sidebar-width: 240px;
  --header-height: 56px;
  --content-max: 980px;
  --transition: 200ms ease;
}
html, body { height: 100%; }
body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--canvas);
  -webkit-tap-highlight-color: transparent;
  overflow: hidden;
}
.reader { display: flex; height: 100dvh; }

/* ── 侧栏（浅灰，低对比） ─────────────────────────────── */
.doc-list {
  width: var(--sidebar-width); min-width: var(--sidebar-width);
  background: var(--sidebar);
  color: var(--ink);
  border-right: 1px solid var(--border);
  display: flex; flex-direction: column;
  height: 100dvh;
  padding-top: env(safe-area-inset-top);
}
.doc-list-head {
  height: var(--header-height);
  padding: 0 20px;
  display: flex; align-items: center;
}
.doc-list-head h1 {
  font-size: 15px; font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink-strong);
}
.search {
  margin: 12px 16px; padding: 8px 14px;
  background: var(--canvas); color: var(--ink);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-size: 14px; outline: none;
}
.search::placeholder { color: var(--muted); }
.doc-items { list-style: none; flex: 1; overflow-y: auto; padding: 8px; }
.doc-item {
  padding: 10px 14px; margin-bottom: 1px;
  border-radius: var(--radius-sm); cursor: pointer;
  transition: background var(--transition);
}
.doc-item:hover { background: rgba(0,0,0,.04); }
.doc-item.active { background: var(--canvas); box-shadow: inset 2px 0 0 var(--blue); }
.doc-name { font-size: 14px; font-weight: 400; color: var(--ink); word-break: break-all; }
.doc-sub { font-size: 12px; color: var(--muted); margin-top: 2px; }
.badge { font-size: 11px; padding: 1px 7px; border-radius: var(--radius-pill); margin-left: 5px; font-weight: 400; }
.badge.ok { background: rgba(0,102,204,.12); color: var(--blue); }
.badge.pending { background: rgba(0,0,0,.06); color: var(--muted); }
.doc-item.empty, li.empty { color: var(--muted); font-size: 13px; padding: 20px; text-align: center; }
.list-overlay { display: none; }
.list-toggle { display: none; }
.doc-list-footer { padding: 12px 16px; border-top: 1px solid var(--border); }
.btn-add-doc {
  width: 100%; padding: 10px;
  background: var(--blue); color: #fff;
  border: none; border-radius: var(--radius-pill);
  cursor: pointer; font-size: 14px;
  transition: background var(--transition);
}
.btn-add-doc:hover { background: var(--blue-focus); }

/* ── 主区 ─────────────────────────────── */
.reader-main {
  flex: 1; display: flex; flex-direction: column;
  min-width: 0; height: 100dvh; background: var(--canvas);
}
.reader-head {
  display: flex; align-items: center; gap: 12px;
  height: var(--header-height); padding: 0 24px;
  border-bottom: 1px solid var(--border); background: var(--canvas);
}
.head-info { flex: 1; min-width: 0; }
.head-info h2 { font-size: 17px; font-weight: 600; letter-spacing: -0.01em; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: var(--ink-strong); }
.doc-meta { font-size: 13px; color: var(--muted); margin-top: 2px; }
.summary-toggle, .export-btn {
  padding: 6px 16px; font-size: 14px; cursor: pointer;
  background: transparent; border: 1px solid var(--border);
  border-radius: var(--radius-pill); color: var(--ink); white-space: nowrap;
  transition: background var(--transition);
}
.summary-toggle:hover, .export-btn:hover { background: rgba(0,0,0,.04); }
.summary-toggle:active, .export-btn:active { transform: scale(0.95); }

/* 摘要折叠条（羊皮纸） */
.summary-bar {
  padding: 16px 24px; background: var(--parchment);
  border-bottom: 1px solid var(--border);
  font-size: 14px; line-height: 1.6; color: var(--ink);
}
.summary-bar .sum-field { margin-bottom: 6px; }
.summary-bar b { color: var(--ink-strong); margin-right: 4px; }

/* 正文（白底 + 柔和字 + 980px 居中，17px） */
.doc-body {
  flex: 1; overflow-y: auto;
  background: var(--canvas);
  color: var(--ink);
  font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 17px; line-height: 1.47;
  overflow-wrap: anywhere;
  max-width: var(--content-max); width: 100%; margin: 0 auto;
  padding: 48px 24px 80px;
}
.doc-body h1, .doc-body h2, .doc-body h3, .doc-body h4 {
  font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink-strong);
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 1.5em 0 .6em; line-height: 1.2;
}
.doc-body h1 { font-size: 28px; text-align: center; }
.doc-body h2 { font-size: 22px; }
.doc-body h3 { font-size: 18px; }
.doc-body p { margin: .5em 0; text-indent: 2em; }
.doc-body table { border-collapse: collapse; width: 100%; margin: 1em 0; font-size: 15px; }
.doc-body th, .doc-body td { border: 1px solid var(--hairline); padding: 8px 12px; text-align: left; }
.doc-body th { background: var(--parchment); font-weight: 600; }
.doc-body img { max-width: 100%; height: auto; display: block; margin: 1em auto; }
.doc-body blockquote { border-left: 3px solid var(--hairline); padding-left: 1em; color: var(--muted); margin: 1em 0; }
.doc-body code { background: var(--parchment); padding: 1px 5px; border-radius: var(--radius-xs); font-size: 15px; }
.doc-body pre { background: var(--parchment); padding: 14px; border-radius: var(--radius-sm); overflow-x: auto; margin: 1em 0; }
.doc-body pre code { background: none; }

/* 公式：可点击 + 悬停高亮 + 选中高亮（淡蓝） */
.doc-body .math {
  cursor: pointer; border-radius: var(--radius-xs); padding: 0 2px;
  transition: background var(--transition);
}
.doc-body .math:hover { background: rgba(0,102,204,.06); }
.doc-body .math.selected { background: rgba(0,102,204,.12); outline: 1.5px solid var(--blue); }
.doc-body .math-display { display: block; text-align: center; margin: 1em 0; }
.doc-body .math-display .katex-display { overflow-x: auto; -webkit-overflow-scrolling: touch; max-width: 100%; padding: 2px 0; }

/* 空状态（纯文字提示，无按钮） */
.empty-state {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  min-height: 100%; text-align: center; color: var(--muted); padding: 40px 20px;
}
.empty-title {
  display: inline-block;
  font-size: 16px; font-weight: 500;
  color: #1d1d1f;           /* 黑色字体 */
  padding: 10px 28px;
  border: 1px solid var(--hairline);
  border-radius: 10px;      /* 圆角长方形 */
  cursor: pointer;
  margin-bottom: 16px;
  transition: background var(--transition);
}
.empty-title:hover { background: rgba(0,0,0,.04); }
.empty-hint { font-size: 14px; color: var(--muted); margin: 4px 0; }

/* 弹窗与选区的虚线连接 */
.connector {
  position: fixed; inset: 0; z-index: 590;
  pointer-events: none; width: 100%; height: 100%;
  display: none;
}
.connector path { stroke: var(--muted); stroke-width: 1.5; stroke-dasharray: 5 5; fill: none; }

/* 浮动解释气泡（追问输入在气泡底部，可拖动） */
.explain-panel {
  position: fixed; z-index: 600; max-width: 400px; min-width: 280px;
  background: var(--canvas); border: 1px solid var(--hairline); border-radius: var(--radius-lg);
  box-shadow: 0 4px 24px rgba(0,0,0,.08);
  padding: 18px; font-size: 15px;
  max-height: 72vh; overflow-y: auto;
}
.panel-head { font-weight: 600; letter-spacing: -0.01em; margin-bottom: 10px; padding-right: 24px; word-break: break-all; color: var(--ink-strong); cursor: move; user-select: none; }
.panel-close { position: absolute; top: 16px; right: 16px; background: none; border: none; font-size: 20px; cursor: pointer; color: var(--muted); line-height: 1; padding: 0; }
.panel-field { margin-bottom: 8px; line-height: 1.55; color: var(--ink); }
.panel-field b { color: var(--blue); margin-right: 4px; }
.panel-md p { margin: 0; }
.explain-panel table { border-collapse: collapse; width: 100%; margin: 8px 0; font-size: 14px; }
.explain-panel th, .explain-panel td { border: 1px solid var(--hairline); padding: 5px 9px; text-align: left; }
.explain-panel th { background: var(--parchment); font-weight: 600; }
.panel-loading { color: var(--muted); padding: 8px 0; display: flex; align-items: center; gap: 8px; }
.panel-loading::before { content: ""; width: 14px; height: 14px; flex-shrink: 0; border: 2px solid var(--hairline); border-top-color: var(--blue); border-radius: 50%; animation: spin .8s linear infinite; }
.panel-error { color: var(--danger); padding: 8px 0; }
.panel-qa-list { margin-top: 10px; border-top: 1px solid var(--border); padding-top: 10px; }
.qa-item { margin-bottom: 10px; }
.qa-item.user { text-align: right; }
.qa-item.user .qa-q { display: inline-block; background: var(--blue); color: #fff; padding: 7px 14px; border-radius: var(--radius-lg) var(--radius-lg) 4px var(--radius-lg); font-size: 14px; max-width: 85%; text-align: left; }
.qa-item.ai .qa-a { background: var(--parchment); padding: 9px 14px; border-radius: var(--radius-lg) var(--radius-lg) var(--radius-lg) 4px; line-height: 1.55; font-size: 14px; color: var(--ink); }
.panel-ask { display: flex; gap: 6px; margin-top: 12px; border-top: 1px solid var(--border); padding-top: 12px; }
.panel-input { flex: 1; padding: 8px 12px; border: 1px solid var(--hairline); border-radius: var(--radius-pill); font-size: 14px; outline: none; min-width: 0; background: var(--canvas); color: var(--ink); }
.panel-input:focus { border-color: var(--blue); }
.panel-ask-btn { padding: 8px 18px; background: var(--blue); color: #fff; border: none; border-radius: var(--radius-pill); cursor: pointer; font-size: 14px; white-space: nowrap; transition: background var(--transition); }
.panel-ask-btn:hover { background: var(--blue-focus); }
.panel-ask-btn:active { transform: scale(0.95); }

/* 底部专利提问对话框 */
.qa-bar {
  border-top: 1px solid var(--border);
  background: var(--canvas); flex-shrink: 0;
  display: flex; flex-direction: column;
}
.qa-bar-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 24px; cursor: pointer; user-select: none;
}
.qa-bar-title { font-size: 14px; color: var(--muted); font-weight: 400; }
.qa-toggle { background: none; border: none; cursor: pointer; color: var(--blue); font-size: 14px; padding: 2px 6px; }
.qa-messages {
  overflow-y: auto; max-height: 45vh; padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  -webkit-overflow-scrolling: touch;
}
.qa-input-row {
  display: flex; gap: 8px; padding: 12px 24px;
  padding-bottom: calc(12px + env(safe-area-inset-bottom));
}
.qa-input-row input {
  flex: 1; padding: 10px 18px; border: 1px solid var(--hairline);
  border-radius: var(--radius-pill); font-size: 15px; outline: none; min-width: 0;
  background: var(--canvas); color: var(--ink);
}
.qa-input-row input:focus { border-color: var(--blue); }
.qa-input-row button {
  padding: 10px 22px; background: var(--blue); color: #fff;
  border: none; border-radius: var(--radius-pill); cursor: pointer; font-size: 15px;
  white-space: nowrap; transition: background var(--transition);
}
.qa-input-row button:hover { background: var(--blue-focus); }
.qa-input-row button:active { transform: scale(0.95); }

/* 余额显示 */
.balance-display { font-size: 13px; color: var(--muted); white-space: nowrap; margin-left: 4px; }

/* 激活码弹窗 */
.activation-modal {
  position: fixed; inset: 0; z-index: 900;
  background: rgba(0,0,0,.45);
  display: flex; align-items: center; justify-content: center;
  padding: 20px;
}
.activation-box {
  background: var(--canvas); border-radius: var(--radius-lg);
  padding: 30px 26px; width: 100%; max-width: 360px;
  text-align: center;
}
.activation-box h3 { font-size: 18px; font-weight: 600; letter-spacing: -0.01em; margin-bottom: 8px; color: var(--ink-strong); }
.activation-hint { font-size: 13px; color: var(--muted); margin-bottom: 18px; }
.activation-box input {
  width: 100%; padding: 11px 14px; border: 1px solid var(--hairline);
  border-radius: var(--radius-sm); font-size: 15px; outline: none;
  text-align: center; letter-spacing: 1px; margin-bottom: 14px;
}
.activation-box input:focus { border-color: var(--blue); }
.activation-box button {
  width: 100%; padding: 11px; background: var(--blue); color: #fff;
  border: none; border-radius: var(--radius-pill); cursor: pointer; font-size: 15px;
  transition: background var(--transition);
}
.activation-box button:hover { background: var(--blue-focus); }
.activation-error { font-size: 13px; color: var(--danger); margin-top: 10px; min-height: 18px; }

/* 淡入过渡（避免内容生硬突然出现） */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-in { animation: fadeIn 0.25s ease; }
@keyframes spin { to { transform: rotate(360deg); } }

/* hidden 属性强制隐藏（覆盖 display:flex 等） */
[hidden] { display: none !important; }

/* ── 响应式（移动端） ───────────────────── */
@media (max-width: 768px) {
  .doc-list {
    position: fixed; left: 0; top: 0; z-index: 500;
    transform: translateX(-100%); transition: transform var(--transition);
  }
  .doc-list.open { transform: translateX(0); }
  .list-overlay.show { display: block; position: fixed; inset: 0; background: rgba(0,0,0,.4); z-index: 499; }
  .list-toggle { display: block; font-size: 20px; background: none; border: none; cursor: pointer; color: var(--ink); }
  .doc-body { padding: 32px 16px 60px; font-size: 16px; line-height: 1.5; }
  .doc-body p { text-indent: 1.5em; }
  .explain-panel { max-width: 100%; max-height: 75vh; }
}

/* ── 墨元智科统一 UI：答疑工作台 ─────────────────────────────── */
:root {
  --canvas: #ffffff;
  --sidebar: #f7faff;
  --parchment: #eef4ff;
  --ink: #40516c;
  --ink-strong: #0b1630;
  --muted: #8290a6;
  --border: #dce5f1;
  --hairline: #e4ebf5;
  --blue: #2364f5;
  --blue-focus: #1548c4;
  --sky-blue: #5c91ff;
  --radius-sm: 10px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --sidebar-width: 278px;
  --header-height: 76px;
  --transition: 180ms ease;
}

body.reader {
  background: #f5f8fc;
  color: var(--ink);
  font-family: "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", Arial, sans-serif;
}
.doc-list {
  background: linear-gradient(180deg, #ffffff 0%, #f5f9ff 100%);
  border-right: 1px solid var(--border);
  box-shadow: 8px 0 26px rgba(16, 38, 78, .045);
}
.doc-list-head {
  height: auto;
  min-height: 76px;
  padding: 18px 17px 14px;
  border-bottom: 1px solid var(--border);
}
.qa-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink-strong);
  text-decoration: none;
}
.qa-brand-mark {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  flex: 0 0 36px;
  border: 1px solid #d7e4f6;
  border-radius: 11px;
  background: linear-gradient(145deg, #eff5ff, #dce9ff);
  color: var(--blue);
  font: 800 14px/1 "Microsoft YaHei", sans-serif;
  box-shadow: 0 6px 14px rgba(35, 100, 245, .10);
}
.qa-brand span { display: flex; min-width: 0; flex-direction: column; line-height: 1.15; }
.qa-brand b { font-size: 16px; font-weight: 780; letter-spacing: .04em; }
.qa-brand small { margin-top: 5px; color: var(--muted); font-size: 11px; letter-spacing: .04em; }
.search {
  height: 42px;
  margin: 14px 16px 10px;
  padding: 9px 13px;
  border: 1px solid var(--border);
  border-radius: 11px;
  background: rgba(255,255,255,.86);
  box-shadow: 0 6px 16px rgba(17, 47, 98, .04);
  color: var(--ink-strong);
}
.search:focus { border-color: #aec7ff; box-shadow: 0 0 0 3px rgba(35,100,245,.10); }
.doc-items { padding: 8px 10px; }
.doc-item { padding: 11px 12px; margin-bottom: 4px; border: 1px solid transparent; border-radius: 11px; }
.doc-item:hover { border-color: #dbe7f9; background: #f0f5ff; }
.doc-item.active { border-color: #bfd2f8; background: #eaf1ff; box-shadow: none; }
.doc-name { color: var(--ink); font-size: 13px; font-weight: 600; }
.doc-sub { color: var(--muted); font-size: 11px; }
.badge.ok { background: #e6f4ee; color: #187552; }
.doc-list-footer { padding: 14px 16px calc(14px + env(safe-area-inset-bottom)); border-top: 1px solid var(--border); background: rgba(255,255,255,.58); }
.btn-add-doc {
  min-height: 44px;
  border-radius: 11px;
  background: linear-gradient(135deg, #286bfb, #1f54d1);
  font-weight: 700;
  box-shadow: 0 10px 20px rgba(35,100,245,.19);
}
.btn-add-doc:hover { background: var(--blue-focus); }
.reader-main { background: #f5f8fc; }
.reader-head {
  min-height: 76px;
  height: auto;
  padding: 15px 28px;
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,.92);
  box-shadow: 0 2px 9px rgba(17,35,68,.035);
}
.head-info h2 { color: var(--ink-strong); font-size: 17px; font-weight: 760; }
.doc-meta { color: var(--muted); font-size: 12px; }
.summary-toggle, .export-btn {
  min-height: 38px;
  border-color: var(--border);
  border-radius: 10px;
  background: #fff;
  color: #40516c;
  font-weight: 700;
}
.summary-toggle:hover, .export-btn:hover { border-color: #aec7ff; background: #eef4ff; color: var(--blue); }
.balance-display { color: var(--muted); font-size: 12px; }
.summary-bar {
  margin: 14px 24px 0;
  padding: 15px 18px;
  border: 1px solid #d5e3f7;
  border-radius: 15px;
  background: rgba(255,255,255,.76);
  box-shadow: 0 8px 20px rgba(17, 47, 98, .055);
  color: var(--ink);
}
.summary-bar b { color: var(--blue); }
.doc-body {
  max-width: none;
  width: 100%;
  margin: 0;
  padding: 32px clamp(24px, 8vw, 120px) 64px;
  background: #f5f8fc;
  color: var(--ink);
  font-size: 16px;
  line-height: 1.8;
}
.doc-body h1, .doc-body h2, .doc-body h3, .doc-body h4 { color: var(--ink-strong); }
.doc-body th { background: #eef4ff; color: var(--ink-strong); }
.doc-body code, .doc-body pre { background: #eef4ff; }
.empty-state {
  min-height: calc(100% - 12px);
  max-width: 960px;
  margin: 6px auto;
  padding: 56px 28px;
  border: 1px solid #dbe7f7;
  border-radius: 24px;
  background: radial-gradient(circle at 75% 15%, rgba(117,164,255,.17), transparent 34%), linear-gradient(145deg, rgba(255,255,255,.93), rgba(244,249,255,.76));
  box-shadow: 0 18px 40px rgba(24, 59, 121, .07);
}
.empty-kicker { margin-bottom: 16px; color: var(--blue); font-size: 11px; font-weight: 800; letter-spacing: .16em; }
.empty-title {
  margin-bottom: 14px;
  padding: 0;
  border: 0;
  color: var(--ink-strong);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 780;
  letter-spacing: -.04em;
}
.empty-title:hover { background: transparent; color: var(--blue); }
.empty-hint { color: var(--muted); font-size: 14px; }
.empty-features { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; margin: 22px 0 9px; }
.empty-features span { padding: 7px 11px; border: 1px solid #d6e4f8; border-radius: 999px; background: rgba(255,255,255,.68); color: #58709a; font-size: 12px; }
.qa-bar {
  margin: 0 24px 16px;
  border: 1px solid #d5e3f7;
  border-radius: 18px;
  background: rgba(255,255,255,.78);
  box-shadow: 0 14px 32px rgba(23,51,104,.08);
  overflow: hidden;
}
.qa-bar-header { padding: 11px 17px; background: rgba(241,246,255,.72); }
.qa-bar-title { color: var(--ink); font-weight: 700; }
.qa-toggle { color: var(--blue); font-weight: 700; }
.qa-input-row { padding: 10px 12px 12px; }
.qa-input-row input { min-height: 44px; border-color: #cbd9ee; background: rgba(255,255,255,.9); }
.qa-input-row button { min-height: 44px; border-radius: 10px; background: var(--blue); font-weight: 700; }
.explain-panel { border-color: #d5e3f7; background: rgba(255,255,255,.88); backdrop-filter: blur(16px); box-shadow: 0 18px 44px rgba(14,40,86,.14); }
.activation-modal { background: rgba(11,29,61,.32); backdrop-filter: blur(5px); }
.activation-box { border: 1px solid rgba(255,255,255,.9); border-radius: 20px; box-shadow: 0 28px 72px rgba(12,29,63,.18); }

@media (max-width: 768px) {
  .doc-list { width: min(86vw, 320px); min-width: 0; box-shadow: 18px 0 46px rgba(8,29,70,.18); }
  .reader-head { min-height: 68px; padding: 12px 16px 12px 60px; padding-top: calc(12px + env(safe-area-inset-top)); }
  .reader-head .summary-toggle, .reader-head .export-btn { padding: 6px 10px; font-size: 12px; }
  .doc-body { padding: 18px 14px 40px; font-size: 15px; }
  .empty-state { min-height: calc(100% - 4px); margin: 2px 0; padding: 40px 18px; border-radius: 19px; }
  .empty-title { font-size: 25px; }
  .empty-kicker { font-size: 10px; letter-spacing: .10em; }
  .summary-bar { margin: 9px 12px 0; padding: 12px 13px; }
  .qa-bar { margin: 0 12px 10px; border-radius: 15px; }
  .qa-input-row { padding: 8px 9px calc(9px + env(safe-area-inset-bottom)); }
  .qa-input-row input { min-width: 0; font-size: 14px; }
  .qa-input-row button { padding-inline: 15px; }
}