/* ============================================================
   AI 产品经理&运营 进阶手册 · 黑白灰版
   设计约束：纯黑白灰配色 / 支持明暗切换 / 全直角（无圆角）
   ============================================================ */

/* ---------- 主题变量 ---------- */
:root {
  --bg: #ffffff;
  --bg-alt: #f2f2f2;
  --bg-elev: #ffffff;
  --bg-code: #f5f5f5;
  --text: #111111;
  --text-dim: #555555;
  --text-faint: #888888;
  --border: #cccccc;
  --border-strong: #000000;
  --accent: #333333;
  --accent-soft: #e6e6e6;
  --shadow: rgba(0, 0, 0, 0.12);
  --done: #000000;
}

[data-theme="dark"] {
  --bg: #0d0d0d;
  --bg-alt: #161616;
  --bg-elev: #181818;
  --bg-code: #1c1c1c;
  --text: #f0f0f0;
  --text-dim: #a0a0a0;
  --text-faint: #6e6e6e;
  --border: #333333;
  --border-strong: #ffffff;
  --accent: #cccccc;
  --accent-soft: #262626;
  --shadow: rgba(0, 0, 0, 0.5);
  --done: #ffffff;
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei",
    "PingFang SC", "Hiragino Sans GB", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* 全直角：显式清零所有可能的圆角 */
button, input, textarea, select, .card, .callout, .codebox,
.toc-item, .tag, .progress-track, .modal, .note-panel, .seg {
  border-radius: 0;
}

a { color: var(--text); }

/* ---------- 布局 ---------- */
.app {
  display: grid;
  grid-template-columns: 280px 1fr;
  min-height: 100vh;
}

/* ---------- 侧边栏 ---------- */
.sidebar {
  background: var(--bg-alt);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-height: 0;
  /* 固定显示在视口左侧，长页面下拉时导航不丢 */
  position: sticky;
  top: 0;
  align-self: start;
  height: 100vh;
  max-height: 100vh;
  overflow: hidden;
}

.sidebar-head {
  padding: 18px 18px 14px;
  border-bottom: 1px solid var(--border);
}

.sidebar-head .brand {
  font-size: 13px;
  letter-spacing: 1px;
  color: var(--text-dim);
  text-transform: uppercase;
}

.sidebar-head .title {
  font-size: 16px;
  font-weight: 700;
  margin-top: 4px;
}

.progress-wrap { padding: 14px 18px; border-bottom: 1px solid var(--border); }
.progress-meta {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-dim);
  margin-bottom: 6px;
}
.progress-track {
  height: 8px;
  background: var(--bg-code);
  border: 1px solid var(--border);
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  width: 0%;
  background: var(--border-strong);
  transition: width .3s ease;
}

.toc-scroll {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  padding: 10px 0;
}
.toc-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  border-left: 3px solid transparent;
  padding: 10px 16px;
  cursor: pointer;
  color: var(--text);
  font-size: 13.5px;
  font-family: inherit;
}
.toc-item:hover { background: var(--accent-soft); }
.toc-item.active { border-left-color: var(--border-strong); background: var(--accent-soft); }
.toc-item .t-main { display: flex; flex-direction: column; }
.toc-item .t-day { font-size: 11px; color: var(--text-faint); display: block; }
.toc-item .t-title { font-weight: 500; }

/* 折叠分组（目录树） */
.toc-group {
  display: flex; align-items: center; gap: 6px; width: 100%;
  text-align: left; background: var(--bg-elev);
  border: none; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border);
  padding: 9px 16px; cursor: pointer; color: var(--text);
  font-size: 12px; font-weight: 700; letter-spacing: .5px; font-family: inherit;
}
.toc-group:hover { background: var(--accent-soft); }
.toc-group .arrow { display: inline-block; font-size: 10px; transition: transform .15s ease; }
.toc-section.collapsed .arrow { transform: rotate(-90deg); }
.toc-group .g-name { flex: 1 1 auto; }
.toc-group .gc { font-weight: 500; font-size: 11px; color: var(--text-dim); }
.toc-children { overflow: hidden; }
.toc-section.collapsed .toc-children { display: none; }
.toc-children .toc-item { padding-left: 26px; }

/* ---------- 主区 ---------- */
.main { display: flex; flex-direction: column; min-width: 0; }

.topbar {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; gap: 12px;
  padding: 12px 22px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.topbar .page-title { font-weight: 700; font-size: 15px; }
.topbar .spacer { flex: 1 1 auto; }

.seg {
  display: inline-flex;
  border: 1px solid var(--border-strong);
}
.seg button {
  background: var(--bg-elev);
  color: var(--text);
  border: none;
  border-right: 1px solid var(--border-strong);
  padding: 7px 14px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
}
.seg button:last-child { border-right: none; }
.seg button.active { background: var(--border-strong); color: var(--bg); }

.btn {
  background: var(--bg-elev);
  color: var(--text);
  border: 1px solid var(--border-strong);
  padding: 7px 14px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
}
.btn:hover { background: var(--accent-soft); }
.btn:active { transform: translateY(1px); }
.btn.primary { background: var(--border-strong); color: var(--bg); }
.btn.primary:hover { opacity: .85; }
.icon-btn {
  width: 34px; height: 34px;
  display: inline-flex; align-items: center; justify-content: center;
  padding: 0;
}

/* ---------- 内容 ---------- */
.content { padding: 26px 30px 80px; max-width: 920px; width: 100%; margin: 0 auto; }

.hero {
  border: 1px solid var(--border);
  background: var(--bg-alt);
  padding: 22px 24px;
  margin-bottom: 26px;
}
.hero h1 { margin: 0 0 6px; font-size: 24px; }
.hero .sub { color: var(--text-dim); font-size: 14px; margin-bottom: 18px; }
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--border); border: 1px solid var(--border); }
.stat { background: var(--bg-elev); padding: 14px; text-align: center; }
.stat .num { font-size: 26px; font-weight: 800; }
.stat .lbl { font-size: 12px; color: var(--text-dim); margin-top: 2px; }

.day { border: 1px solid var(--border); margin-bottom: 22px; background: var(--bg-elev); }
.day-head {
  display: flex; align-items: flex-start; gap: 12px;
  padding: 16px 20px; border-bottom: 1px solid var(--border); background: var(--bg-alt);
}
.day-head .badge {
  font-size: 11px; letter-spacing: 1px; color: var(--text-dim);
  border: 1px solid var(--border); padding: 3px 8px; white-space: nowrap; flex-shrink: 0;
}
.day-head .meta { flex: 1 1 auto; }
.day-head h2 { margin: 2px 0 2px; font-size: 18px; }
.day-head .week { font-size: 12px; color: var(--text-faint); }
.day-body { padding: 18px 20px; }
.day-intro {
  border-left: 3px solid var(--border-strong);
  padding: 6px 14px; color: var(--text-dim);
  font-size: 14px; margin-bottom: 16px;
}
.day-foot { padding: 12px 20px; border-top: 1px solid var(--border); display: flex; align-items: center; gap: 12px; }
.day-foot .state { font-size: 12px; color: var(--text-dim); }
.day-foot.done .state { color: var(--text); font-weight: 600; }

/* 区块 */
.block { margin: 16px 0; }
.block h3 { font-size: 15px; margin: 0 0 8px; padding-bottom: 4px; border-bottom: 1px dashed var(--border); }
.block p { margin: 6px 0; }
.block ul { margin: 6px 0; padding-left: 20px; }
.block li { margin: 4px 0; }

.callout {
  border: 1px solid var(--border-strong);
  border-left-width: 4px;
  padding: 12px 16px;
  background: var(--bg-alt);
}
.callout .c-title { font-weight: 700; font-size: 13px; margin-bottom: 6px; text-transform: uppercase; letter-spacing: .5px; }
.callout.tip { border-left-color: var(--text); }
.callout.warn { border-left-color: var(--text); background: var(--accent-soft); }
.callout.rule { border-left-color: var(--border-strong); }
.callout.case { border-left-color: var(--text-dim); }
.callout ul { margin: 4px 0; padding-left: 18px; }

table.tbl { width: 100%; border-collapse: collapse; font-size: 13.5px; margin: 6px 0; }
table.tbl th, table.tbl td { border: 1px solid var(--border); padding: 8px 10px; text-align: left; vertical-align: top; }
table.tbl th { background: var(--bg-alt); font-weight: 700; }
.table-scroll { overflow-x: auto; border: 1px solid var(--border); }

.codebox { border: 1px solid var(--border-strong); background: var(--bg-code); margin: 6px 0; }
.codebox .c-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 6px 10px; border-bottom: 1px solid var(--border); font-size: 11px; color: var(--text-dim);
}
.codebox pre { margin: 0; padding: 12px; overflow-x: auto; font-size: 13px; }
.codebox code { font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; white-space: pre; }

.steps { list-style: none; counter-reset: s; padding: 0; margin: 6px 0; }
.steps li { counter-increment: s; position: relative; padding: 8px 8px 8px 40px; border: 1px solid var(--border); margin-bottom: -1px; }
.steps li::before {
  content: counter(s); position: absolute; left: 8px; top: 8px;
  width: 22px; height: 22px; border: 1px solid var(--border-strong);
  display: flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 700;
}

/* 批注 */
.note-btn {
  font-size: 11px; padding: 2px 8px; border: 1px solid var(--border); background: var(--bg-elev);
  cursor: pointer; color: var(--text-dim); font-family: inherit;
}
.note-btn:hover { background: var(--accent-soft); color: var(--text); }
.note-area {
  width: 100%; min-height: 64px; margin-top: 8px; padding: 8px 10px;
  border: 1px solid var(--border-strong); background: var(--bg); color: var(--text);
  font-family: inherit; font-size: 13px; resize: vertical;
}

/* ---------- 词汇表 ---------- */
.glossary-search {
  display: flex; gap: 10px; margin-bottom: 18px;
}
.glossary-search input {
  flex: 1 1 auto; padding: 10px 12px; border: 1px solid var(--border-strong);
  background: var(--bg-elev); color: var(--text); font-size: 14px; font-family: inherit;
}
.glossary-cats { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }
.cat-chip {
  border: 1px solid var(--border); background: var(--bg-elev); color: var(--text-dim);
  padding: 5px 12px; cursor: pointer; font-size: 12.5px; font-family: inherit;
}
.cat-chip.active { background: var(--border-strong); color: var(--bg); border-color: var(--border-strong); }
.gloss-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 14px; }
.gloss-card { border: 1px solid var(--border); background: var(--bg-elev); padding: 14px 16px; }
.gloss-card .g-term { font-weight: 700; font-size: 15px; }
.gloss-card .g-cat { font-size: 11px; color: var(--text-faint); border: 1px solid var(--border); padding: 1px 7px; margin-left: 8px; }
.gloss-card .g-def { font-size: 13.5px; color: var(--text-dim); margin-top: 8px; }
.empty { color: var(--text-faint); padding: 30px; text-align: center; border: 1px dashed var(--border); }

/* ---------- 批注面板 ---------- */
.note-panel {
  position: fixed; top: 0; right: 0; height: 100vh; width: 340px;
  background: var(--bg); border-left: 1px solid var(--border-strong);
  transform: translateX(100%); transition: transform .25s ease; z-index: 50;
  display: flex; flex-direction: column;
}
.note-panel.open { transform: translateX(0); }
.note-panel .np-head { padding: 14px 16px; border-bottom: 1px solid var(--border); display: flex; align-items: center; justify-content: space-between; font-weight: 700; }
.note-panel .np-body { flex: 1 1 auto; overflow-y: auto; padding: 12px 16px; }
.note-item { border: 1px solid var(--border); padding: 10px 12px; margin-bottom: 10px; }
.note-item .ni-where { font-size: 11px; color: var(--text-faint); }
.note-item .ni-text { font-size: 13px; margin-top: 4px; white-space: pre-wrap; word-break: break-word; }
.scrim { position: fixed; inset: 0; background: var(--shadow); display: none; z-index: 40; }
.scrim.open { display: block; }

/* ---------- 响应式 ---------- */
.menu-btn { display: none; }
@media (max-width: 860px) {
  .app { grid-template-columns: 1fr; }
  .sidebar { position: fixed; left: 0; top: 0; bottom: 0; width: 280px; z-index: 60; transform: translateX(-100%); transition: transform .25s ease; }
  .sidebar.open { transform: translateX(0); }
  .menu-btn { display: inline-flex; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .content { padding: 18px 16px 70px; }
}