/* ============================================
   学习计划页（learn.html）
   复用 style.css 的 CSS 变量，随主题自动切换
   布局：左侧平铺大纲（锚点 + scroll-spy）+ 右侧整篇文档（三态）
   ============================================ */

/* 三态固定配色（不随主题变化）：已学会=绿、已生成=白、待生成=灰 */

.learn-main {
  max-width: 1440px;
  margin: 0 auto;
  padding: 1.1rem 2rem 3rem;
  position: relative;
  z-index: 1;
}

/* ---- 学习页顶部返回首页链接（放左侧）---- */
.learn-nav {
  position: absolute; top: 0.75rem; left: 1.1rem; z-index: 10;
}
.learn-nav-link {
  display: inline-flex; align-items: center; gap: 0.25rem;
  font-size: 0.78rem; color: var(--blue);
  text-decoration: none; padding: 0.22rem 0.6rem;
  border: 1px solid rgba(var(--brand-rgb),0.3); border-radius: 5px;
  background: rgba(var(--brand-rgb),0.06);
  transition: background var(--ease), border-color var(--ease), transform var(--ease);
}
.learn-nav-link:hover {
  background: rgba(var(--brand-rgb),0.12);
  border-color: rgba(var(--brand-rgb),0.55);
  transform: translateX(-1px);
}

/* ============================================
   Hero：标题 + 生成进度环 + 已学会统计
   ============================================ */
.learn-hero {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; flex-wrap: wrap;
  background: var(--surface);
  border: 1px solid var(--card-border);
  border-radius: 14px;
  padding: 1rem 1.3rem 0.95rem;
  margin-bottom: 1.3rem;
  box-shadow: 0 5px 20px rgba(0,0,0,0.07);
}
.learn-hero-left { flex: 1; min-width: 0; }
.learn-hero-title {
  display: flex; align-items: baseline; gap: 0.6rem; flex-wrap: wrap;
}
.learn-sub {
  margin: 0.4rem 0 0;
  font-size: 0.78rem; line-height: 1.7;
  color: var(--text-fade);
}
.learn-hero-title h1 {
  font-size: 1.5rem; font-weight: 800; letter-spacing: 0.01em;
  background: linear-gradient(120deg, var(--blue), var(--text));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.learn-tag {
  font-size: 0.72rem; color: var(--blue);
  background: rgba(var(--brand-rgb),0.1);
  padding: 0.14rem 0.6rem; border-radius: 4px;
}
.learn-hero-right { display: flex; align-items: center; gap: 1rem; }

/* 生成进度环 */
.skill-ring { position: relative; width: 76px; height: 76px; flex: none; }
.skill-ring svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.ring-bg { fill: none; stroke: var(--code-bg); stroke-width: 9; }
.ring-fg {
  fill: none; stroke: var(--blue); stroke-width: 9; stroke-linecap: round;
  transition: stroke-dashoffset 0.8s var(--ease-spring);
}
.ring-center {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
}
.ring-center b { font-size: 1.1rem; font-weight: 800; line-height: 1; }
.ring-center span { font-size: 0.62rem; color: var(--text-fade); margin-top: 3px; }

.learn-stats { font-size: 0.88rem; color: var(--text-soft); white-space: nowrap; }
.learn-stats .stat-learned b {
  font-size: 1.05rem; font-weight: 800; color: var(--blue);
}

/* ============================================
   两栏布局：左侧平铺大纲 + 右侧整篇文档
   ============================================ */
.learn-layout {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 1.7rem;
  align-items: start;
  margin-top: 1.1rem;
}

/* 梯队统一配色：全部使用主色（原每梯一色，已简化） */
.tier-1, .tier-2, .tier-3, .tier-4, .tier-5, .tier-6 { --tier-c: var(--blue); }

/* ---- 左侧：大纲（sticky 跟随滚动，内部滚动不显示滚动条） ---- */
.learn-outline {
  position: sticky;
  top: 1rem;
  max-height: calc(100vh - 2rem);
  overflow-y: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding: 0 0.35rem 0.4rem 0;
}
.learn-outline::-webkit-scrollbar { display: none; }

.outline-head {
  display: flex; align-items: baseline; justify-content: space-between;
  padding: 0.1rem 0.5rem 0.55rem;
  font-size: 0.82rem;
}
.outline-title { font-weight: 800; }
.outline-meta { font-size: 0.7rem; color: var(--text-fade); }

/* 梯队分组 */
.outline-tier { margin: 0 0 1rem; }
.outline-tier-name {
  font-size: 0.72rem; font-weight: 700; letter-spacing: 0.01em;
  color: var(--tier-c, var(--blue));
  margin: 0 0 0.3rem; padding-left: 0.45rem;
  border-left: 3px solid var(--tier-c, var(--blue));
}

/* 大纲条目（平铺） */
.outline-unit {
  display: flex; align-items: center; gap: 0.5rem;
  padding: 0.4rem 0.5rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.84rem; line-height: 1.35; color: var(--text);
  transition: background var(--ease), opacity var(--ease);
}
.outline-unit:hover { background: rgba(var(--brand-rgb),0.06); }
.outline-unit.active { background: rgba(var(--brand-rgb),0.12); }
.outline-unit.active .ou-title { font-weight: 650; }

.ou-dot { width: 8px; height: 8px; border-radius: 50%; flex: none; }
.ou-num {
  font-family: ui-monospace, monospace; font-weight: 700; font-size: 0.7rem;
  color: var(--text-fade); flex: none; width: 1.7em;
}
.outline-unit.active .ou-num { color: var(--blue); }
.ou-title { flex: 1; }

/* 大纲三态着色（固定配色） */
.ou-pending .ou-dot { background: #9aa0a6; }
/* 待生成单元整行置灰（标题 + 编号，滚动高亮时仍保持灰，仅背景高亮） */
.outline-unit.ou-pending .ou-title,
.outline-unit.ou-pending .ou-num { color: #9aa0a6; }
.ou-active .ou-dot {
  background: #ffffff;
  box-shadow: 0 0 0 1.5px rgba(0,0,0,0.18);
}
.outline-unit.ou-learned { background: rgba(16,185,129,0.08); }
.outline-unit.ou-learned .ou-num { color: #10b981; }
.ou-learned .ou-dot {
  background: #10b981;
  box-shadow: 0 0 0 3px rgba(16,185,129,0.18);
}

/* 大纲底部图例已移除（三态由固定光点色自明，无需说明） */

/* ============================================
   右侧：整篇文档（35 单元分节）
   ============================================ */
.learn-doc {
  background: var(--surface);
  border: 1px solid var(--card-border);
  border-radius: 14px;
  padding: 1.5rem 1.6rem 2rem;
  box-shadow: 0 6px 24px rgba(0,0,0,0.07);
}

/* 梯队分节标题 */
.doc-tier + .doc-tier { margin-top: 2rem; }
.doc-tier-head {
  display: flex; align-items: center; gap: 0.55rem;
  font-size: 1.02rem; font-weight: 800;
  color: var(--tier-c, var(--blue));
  margin: 0 0 0.8rem; padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--tier-c, var(--blue));
}
.doc-tier-num {
  font-family: ui-monospace, monospace; font-size: 0.78rem; font-weight: 800;
  color: #fff; background: var(--tier-c, var(--blue));
  padding: 0.14rem 0.5rem; border-radius: 5px;
}

/* 单元节（scroll-spy 与大纲锚点的定位目标） */
.doc-unit {
  scroll-margin-top: 90px;
  padding: 0.85rem 1rem 0.9rem;
  margin-bottom: 0.65rem;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  background: var(--code-bg);
}

.doc-unit-head { display: flex; align-items: center; gap: 0.55rem; }
.doc-unit-num {
  font-family: ui-monospace, monospace; font-weight: 800; font-size: 0.8rem;
  color: var(--blue); background: rgba(var(--brand-rgb),0.1);
  padding: 0.14rem 0.5rem; border-radius: 5px;
}
.doc-unit-title { flex: 1; font-size: 1rem; font-weight: 700; margin: 0; }
/* 待生成单元的右侧标题置灰 */
.doc-unit.du-pending .doc-unit-title { color: #9aa0a6; }
.doc-wl {
  flex: none; font-size: 0.62rem; font-weight: 800;
  padding: 0.08rem 0.4rem; border-radius: 3px; letter-spacing: 0.04em;
}
.doc-wl.wl-S { color: #0A8F3C; background: rgba(10,143,60,0.12); }
.doc-wl.wl-M { color: #B45309; background: rgba(180,83,9,0.12); }
.doc-wl.wl-L { color: #B91C1C; background: rgba(185,28,28,0.12); }

.doc-state {
  flex: none; margin-left: auto; font-size: 0.72rem;
  padding: 0.12rem 0.55rem; border-radius: 4px; white-space: nowrap;
}
.doc-state.st-learned { color: #10b981; background: rgba(16,185,129,0.14); }
.doc-state.st-active { color: #ffffff; background: rgba(0,0,0,0.45); }
.doc-state.st-pending { color: #6e737a; background: rgba(0,0,0,0.05); }

.doc-prereq { font-size: 0.76rem; color: var(--text-fade); margin: 0.35rem 0 0; }

.doc-body { margin-top: 0.6rem; display: flex; flex-direction: column; gap: 0.5rem; }

/* 未生成占位 */
.doc-note {
  padding: 0.55rem 0.8rem; border-radius: 8px;
  font-size: 0.78rem; line-height: 1.55; color: var(--text-fade);
  border: 1px dashed var(--hairline); background: var(--surface);
}
/* 已生成文章条目 */
.doc-link {
  display: flex; align-items: center; gap: 0.85rem;
  padding: 0.6rem 0.85rem;
  border: 1px solid var(--hairline); border-radius: 9px;
  text-decoration: none; color: var(--text);
  background: var(--surface);
  transition: border-color var(--ease), box-shadow var(--ease), transform var(--ease);
}
.doc-link:hover {
  border-color: rgba(var(--brand-rgb),0.5);
  box-shadow: 0 4px 14px rgba(0,0,0,0.07);
  transform: translateY(-1px);
}
.dl-part {
  flex: none; padding: 0.1rem 0.55rem; border-radius: 4px;
  font-size: 0.72rem; font-weight: 700; color: var(--blue);
  background: rgba(var(--brand-rgb),0.1);
}
.dl-title { flex: 1; font-size: 0.9rem; font-weight: 600; }
.dl-date { flex: none; font-size: 0.72rem; color: var(--text-fade); }
.dl-time {
  display: inline-flex; align-items: center; gap: 0.3rem;
  flex: none; font-size: 0.72rem; color: var(--text-fade);
  white-space: nowrap;
}
.dl-time svg { flex-shrink: 0; opacity: 0.7; }

/* 已学会指示（位于单元头部右上角，紧跟在状态徽标之后；派生只读，全勾才亮） */
.doc-learned {
  display: inline-flex; align-items: center; gap: 0.3rem;
  flex: none; margin-left: 0.2rem;
  font-size: 0.72rem; color: var(--text-soft); cursor: default;
  white-space: nowrap;
}
.doc-learned input {
  width: 14px; height: 14px; margin: 0;
  accent-color: var(--blue); cursor: default;
  opacity: 0.85;
}
.doc-learned input:disabled:checked { accent-color: #10b981; }
.doc-learned.checked { color: #10b981; font-weight: 600; }

/* 每篇已生成文章行：文章链接 + 行尾「已学会」勾选框 */
.doc-link-row {
  display: flex; align-items: center; gap: 0.55rem;
}
.doc-link-row .doc-link { flex: 1; min-width: 0; }
.doc-article-learn {
  flex: none; display: inline-flex; align-items: center; justify-content: center;
  padding: 0.3rem; border-radius: 6px;
  cursor: pointer; color: var(--text-fade);
}
.doc-article-learn:hover { background: rgba(var(--brand-rgb),0.08); }
.doc-article-learn input {
  width: 14px; height: 14px; margin: 0;
  accent-color: var(--blue); cursor: pointer;
}
.doc-article-learn.checked input { accent-color: #10b981; }
.doc-article-learn.checked { color: #10b981; }

/* ============================================
   响应式：移动端大纲变为横向单元条
   ============================================ */
@media (max-width: 640px) {
  .learn-nav { left: 1rem; }
  .learn-main { padding: 1rem 0.8rem 2rem; }
  .learn-hero { padding: 0.95rem 1rem; gap: 0.7rem; flex-direction: column; align-items: stretch; }
  .learn-hero-right { align-self: flex-end; }
  .learn-hero-title h1 { font-size: 1.3rem; }
  .skill-ring { width: 66px; height: 66px; }
  .learn-stats { font-size: 0.8rem; }

  .learn-layout { grid-template-columns: 1fr; gap: 0.9rem; margin-top: 1rem; }

  .learn-outline {
    position: static; top: auto; max-height: none; overflow: visible;
    display: flex; align-items: flex-start; gap: 0.3rem;
    overflow-x: auto; overflow-y: hidden;
    padding: 0.4rem 0.2rem;
  }
  .outline-head { display: none; }
  .outline-tier { display: flex; gap: 0.3rem; flex: none; margin: 0; align-items: stretch; }
  .outline-tier + .outline-tier {
    margin-left: 0.4rem; padding-left: 0.55rem;
    border-left: 1px solid var(--hairline);
  }
  .outline-tier-name { display: none; }
  .outline-unit {
    flex-direction: column; gap: 0.1rem;
    padding: 0.3rem 0.4rem; width: 52px;
    text-align: center; font-size: 0.68rem;
    flex: none;
  }
  .outline-unit.active {
    background: rgba(var(--brand-rgb),0.12);
    box-shadow: inset 0 0 0 1.5px var(--blue);
  }
  .ou-dot { display: none; }
  .ou-num { width: auto; font-size: 0.75rem; }
  .ou-title { display: none; }

  .learn-doc { padding: 1.1rem 0.9rem 1.5rem; }
  .doc-unit { padding: 0.75rem 0.8rem; }
  .doc-unit-head { flex-wrap: wrap; row-gap: 0.35rem; }
  .doc-state { order: 5; width: 100%; margin-left: 0; text-align: center; }
  .dl-date { display: none; }
}

/* ============================================
   暗黑主题适配：三态颜色已在基础规则中固定(绿/白/灰)，
   无需额外覆盖；仅修正右侧 T 编号 pill（--blue 为纯白时白底白字不可见 → 深色字）
   ============================================ */
[data-theme="dark"] .doc-tier-num { color: #202124; }

/* ============================================
   多语言模块：顶部标签页 + 各模块 accent 色
   新增模块：在 :root 加一条 --mod-{key} 命名变量，
   并在 .learn-main[data-module]（当前模块强调色）与
   .mod-tab[data-module]（标签自身固定色）各补一条映射
   ============================================ */
:root {
  --mod-java: #2563eb;
  --mod-python: #0f9d8f;
  --mod-rust: #c05621;
  --mod-go: #0096c7;
  --mod-frontend: #3178c6;
  --mod-cpp: #b91c1c;
  --mod-ai: #7c3aed;
}
/* 当前模块 accent → 梯队边框 / 梯头下划线（随切换变化） */
.learn-main[data-module="java"]       { --module-c: var(--mod-java); }
.learn-main[data-module="python"]     { --module-c: var(--mod-python); }
.learn-main[data-module="rust"]       { --module-c: var(--mod-rust); }
.learn-main[data-module="go"]         { --module-c: var(--mod-go); }
.learn-main[data-module="frontend"] { --module-c: var(--mod-frontend); }
.learn-main[data-module="cpp"]        { --module-c: var(--mod-cpp); }
.learn-main[data-module="ai"]         { --module-c: var(--mod-ai); }
/* 每个标签自己的颜色 → 圆点 / active 底色（不随当前模块漂移） */
.mod-tab[data-module="java"]       { --tab-c: var(--mod-java); }
.mod-tab[data-module="python"]     { --tab-c: var(--mod-python); }
.mod-tab[data-module="rust"]       { --tab-c: var(--mod-rust); }
.mod-tab[data-module="go"]         { --tab-c: var(--mod-go); }
.mod-tab[data-module="frontend"] { --tab-c: var(--mod-frontend); }
.mod-tab[data-module="cpp"]        { --tab-c: var(--mod-cpp); }
.mod-tab[data-module="ai"]         { --tab-c: var(--mod-ai); }

.learn-modules {
  display: flex; align-items: center; gap: 0.5rem;
  flex-wrap: nowrap; overflow-x: auto;
  margin: 0 0 0.9rem;
  padding: 0.1rem 0.2rem 0.25rem;
}
.learn-modules::-webkit-scrollbar { display: none; }

.mod-tab {
  display: inline-flex; align-items: center; gap: 0.4rem;
  flex: none; cursor: pointer;
  font-size: 0.85rem; font-weight: 700;
  color: var(--text-soft);
  background: var(--surface);
  border: 1px solid var(--card-border);
  border-radius: 999px;
  padding: 0.32rem 0.95rem;
  transition: background var(--ease), color var(--ease), border-color var(--ease);
}
.mod-tab:hover {
  color: var(--text);
  border-color: rgba(var(--brand-rgb),0.45);
}
.mod-tab.active {
  color: #fff;
  background: var(--tab-c, var(--module-c, var(--blue)));
  border-color: transparent;
}
.mod-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--tab-c, var(--module-c, var(--blue)));
  flex: none;
}
.mod-tab.active .mod-dot { background: rgba(255,255,255,0.92); }

/* 梯队名边框 / 文档梯头下划线使用模块 accent（文字与编号仍用主题主色，避免暗黑对比度问题） */
.outline-tier-name { border-left-color: var(--module-c, var(--tier-c, var(--blue))); }
.doc-tier-head { border-bottom-color: var(--module-c, var(--tier-c, var(--blue))); }

/* 空模块空态（tiers/units 为空时） */
.learn-empty {
  background: var(--surface);
  border: 1px dashed var(--card-border);
  border-radius: 14px;
  padding: 2.4rem 1.5rem;
  text-align: center;
}
.learn-empty h2 { font-size: 1.15rem; color: var(--text); margin: 0 0 0.55rem; }
.learn-empty p { font-size: 0.84rem; line-height: 1.7; margin: 0; color: var(--text-fade); }