/* 阅读空间：左边文章列表，右边阅读区（复用课时页的正文样式和划线样式） */
.rd { display: grid; grid-template-columns: 260px 1fr; min-height: calc(100vh - 52px); font-family: var(--n-font); color: var(--n-text); }
.rd-side { background: var(--n-side); border-right: 1px solid var(--n-line); padding: 20px 12px; position: sticky; top: 52px; height: calc(100vh - 52px); overflow-y: auto; }
.rd-side h2 { font-size: 15px; font-weight: 600; margin: 0 8px 12px; display: flex; align-items: center; gap: 6px; }
.rd-new { display: flex; align-items: center; gap: 6px; width: 100%; border: 0; background: none; font: inherit; font-size: 14px; color: var(--n-muted); padding: 7px 8px; border-radius: 6px; cursor: pointer; text-align: left; }
.rd-new:hover { background: var(--n-hover); color: var(--n-text); }
.rd-list { margin-top: 6px; }
.rd-list a { display: block; padding: 7px 8px; border-radius: 6px; font-size: 14px; color: var(--n-text); line-height: 1.4; }
.rd-list a:hover { background: var(--n-hover); }
.rd-list a.on { background: rgba(55, 53, 47, .08); font-weight: 600; }
.rd-list a small { display: block; color: var(--n-faint); font-size: 12px; font-weight: 400; margin-top: 2px; }
.rd-list .empty { color: var(--n-faint); font-size: 13px; padding: 8px; }

.rd-main { min-width: 0; padding: 0 56px 80px; }
.rd-inner { max-width: 760px; margin: 0 auto; }

/* 顶部状态条：试用倒计时 / 会员到期时间 / 开通按钮 */
.rd-status { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin: 20px 0 0; padding: 10px 14px; border-radius: 10px; font-size: 14px; background: var(--n-gray-bg); }
.rd-status.trial { background: #e8f1fd; }
.rd-status.ended { background: #fdebec; }
.rd-status .spacer { flex: 1; }
.rd-status b { font-weight: 600; }

.rd-title { font-size: 34px; font-weight: 700; line-height: 1.25; margin: 40px 0 6px; outline: none; border-radius: 4px; }
.rd-title[contenteditable="true"]:hover { background: var(--n-hover); }
.rd-meta { color: var(--n-faint); font-size: 13px; display: flex; gap: 14px; align-items: center; margin-bottom: 26px; }
.rd-meta button { border: 0; background: none; font: inherit; color: var(--n-faint); cursor: pointer; padding: 2px 6px; border-radius: 4px; }
.rd-meta button:hover { background: var(--n-hover); color: var(--n-red); }
.rd-article p { margin: 0 0 14px; }
.rd-tip { color: var(--n-faint); font-size: 13px; margin: 0 0 18px; }

/* 新建文章 */
.rd-form { margin-top: 36px; }
.rd-form h1 { font-size: 28px; margin: 0 0 6px; }
.rd-form > p { color: var(--n-muted); font-size: 14px; margin: 0 0 18px; }
.rd-form input, .rd-form textarea { width: 100%; box-sizing: border-box; border: 1px solid var(--n-line); border-radius: 8px; padding: 10px 12px; font: 16px/1.7 var(--n-content-font); color: var(--n-text); background: #fff; outline: none; }
.rd-form input:focus, .rd-form textarea:focus { border-color: rgba(35, 131, 226, .6); box-shadow: 0 0 0 3px rgba(35, 131, 226, .12); }
.rd-form textarea { min-height: 360px; resize: vertical; margin-top: 10px; }
.rd-form .bar { display: flex; align-items: center; gap: 12px; margin-top: 12px; font-size: 13px; color: var(--n-faint); }
.rd-form .bar .spacer { flex: 1; }
.rd-msg { color: var(--n-red); font-size: 14px; margin-top: 8px; min-height: 1em; }

/* 未登录 / 未开通时的介绍 */
.rd-hero { text-align: center; padding: 70px 0 30px; }
.rd-hero h1 { font-size: 36px; margin: 0 0 12px; }
.rd-hero > p { color: var(--n-muted); font-size: 17px; margin: 0 auto 26px; max-width: 520px; line-height: 1.7; }
.rd-feats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin: 34px 0 0; text-align: left; }
.rd-feats div { border: 1px solid var(--n-line); border-radius: 10px; padding: 14px 16px; font-size: 14px; color: var(--n-muted); line-height: 1.6; }
.rd-feats b { display: block; color: var(--n-text); font-size: 15px; margin-bottom: 2px; }
.rd-small { display: block; font-size: 11px; color: var(--n-faint); margin-top: 4px; }

/* 开通弹窗：月卡 / 年卡 */
.rd-plans { display: grid; gap: 10px; margin: 18px 0 6px; }
.rd-plan { display: flex; align-items: center; gap: 12px; border: 1px solid var(--line, #d2d2d7); border-radius: 14px; padding: 14px 16px; text-align: left; background: #fff; font: inherit; cursor: pointer; transition: border-color .15s, box-shadow .15s; }
.rd-plan:hover { border-color: var(--blue, #1f3fb0); box-shadow: 0 0 0 3px rgba(31, 63, 176, .1); }
.rd-plan .t { flex: 1; }
.rd-plan .t b { display: block; font-size: 16px; }
.rd-plan .t small { color: var(--muted, #6e6e73); font-size: 13px; }
.rd-plan .p { font-size: 20px; font-weight: 700; color: var(--blue, #1f3fb0); }
.rd-plan .p s { font-size: 13px; font-weight: 400; color: var(--faint, #86868b); margin-right: 4px; }

.rd-side-toggle { display: none; }
.rd-side h2 > span { flex: 1; }
.rd-side-hide { border: 0; background: none; font: 18px/1 var(--n-font); color: var(--n-faint); width: 26px; height: 26px; border-radius: 6px; cursor: pointer; flex: none; }
.rd-side-hide:hover { background: var(--n-hover); color: var(--n-text); }
.rd-side-show { display: none; position: sticky; top: 64px; float: left; margin: 12px 0 0 -40px; border: 1px solid var(--n-line); background: #fff; font: 13px var(--n-font); color: var(--n-muted); border-radius: 7px; padding: 5px 10px; cursor: pointer; z-index: 5; }
.rd-side-show:hover { color: var(--n-text); background: var(--n-hover); }
.rd.side-hidden { grid-template-columns: 1fr; }
.rd.side-hidden .rd-side { display: none; }
.rd.side-hidden .rd-side-show { display: block; }
@media (max-width: 860px) {
  .rd { grid-template-columns: 1fr; align-content: start; }
  .rd-side { position: static; height: auto; border-right: 0; border-bottom: 1px solid var(--n-line); padding: 12px 16px; }
  .rd-side.collapsed .rd-list, .rd-side.collapsed .rd-new { display: none; }
  .rd-side h2 { margin: 0; justify-content: space-between; }
  .rd-side-hide, .rd.side-hidden .rd-side-show { display: none; }
  .rd.side-hidden .rd-side { display: block; }
  .rd-side-toggle { display: inline-block; border: 0; background: none; font: inherit; font-size: 13px; color: var(--n-muted); cursor: pointer; }
  .rd-main { padding: 0 16px 60px; }
  .rd-title { font-size: 26px; margin-top: 24px; }
  .rd-meta { flex-wrap: wrap; gap: 6px 14px; }
  .rd-feats { grid-template-columns: 1fr; }
  .rd-hero { padding-top: 40px; }
  .u-margin { right: -6px; }
}

/* 价格卡片：月卡 / 年卡 */
.rd-pricing { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 220px)); justify-content: center; gap: 14px; margin: 34px 0 6px; }
.rd-price { position: relative; display: flex; flex-direction: column; align-items: center; gap: 4px; border: 1.5px solid var(--n-line); border-radius: 14px; background: #fff;
  padding: 20px 14px 16px; font: inherit; color: var(--n-text); cursor: pointer; transition: border-color .15s, box-shadow .15s, transform .15s; }
.rd-price:hover { border-color: var(--blue, #1f3fb0); box-shadow: 0 8px 24px rgba(31, 63, 176, .12); transform: translateY(-2px); }
.rd-price.best { border-color: var(--blue, #1f3fb0); box-shadow: 0 0 0 3px rgba(31, 63, 176, .08); }
.rd-price .tag-best { position: absolute; top: -11px; background: var(--blue, #1f3fb0); color: #fff; font-size: 12px; font-weight: 600; border-radius: 980px; padding: 2px 10px; }
.rd-price .nm { font-size: 15px; color: var(--n-muted); }
.rd-price .pr { font-size: 15px; color: var(--n-text); }
.rd-price .pr b { font-size: 34px; font-weight: 700; letter-spacing: -0.02em; }
.rd-price .pr s { color: var(--n-faint); font-size: 13px; margin-right: 6px; }
.rd-price .pr small { color: var(--n-muted); font-size: 14px; }
.rd-price .sub { font-size: 13px; color: var(--blue, #1f3fb0); min-height: 1.2em; }
.rd-from { font-size: 13px; color: var(--n-muted); }

/* 🔒 锁定 / ✏️ 编辑 切换 */
.rd-mode { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin: 28px 0 0; padding: 10px 12px; border-radius: 12px; background: var(--n-side); border: 1px solid var(--n-line); }
.rd-seg { display: inline-flex; background: rgba(55, 53, 47, .07); border-radius: 9px; padding: 3px; flex-shrink: 0; }
.rd-seg button { border: 0; background: none; font: inherit; font-size: 14px; color: var(--n-muted); padding: 6px 14px; border-radius: 7px; cursor: pointer; white-space: nowrap; transition: background .15s, color .15s; }
.rd-seg button.on { background: #fff; color: var(--n-text); font-weight: 600; box-shadow: 0 1px 3px rgba(0, 0, 0, .12); }
.rd-seg button[data-m="edit"].on { color: #b35c00; }
.rd-seg button:disabled { opacity: .45; cursor: not-allowed; }
.rd-mode-tip { flex: 1; min-width: 220px; font-size: 13px; line-height: 1.6; color: var(--n-muted); }
.rd-mode-tip b { color: var(--n-text); font-weight: 600; }
.rd-mode-tip.edit b { color: #b35c00; }
.rd-mode + .rd-title { margin-top: 28px; }

/* 编辑模式：标题输入框 + 自动变高的正文 */
.rd-title-input { display: block; width: 100%; box-sizing: border-box; border: 0; border-bottom: 1px dashed rgba(179, 92, 0, .45); background: none; font: inherit; font-size: 34px; font-weight: 700; padding: 0 0 4px; }
.rd-title-input:focus { border-bottom-color: #b35c00; }
.rd-edit-body { display: block; width: 100%; box-sizing: border-box; min-height: 320px; resize: none; overflow: hidden; border: 1px solid rgba(179, 92, 0, .3); border-radius: 10px; background: #fffdf8; padding: 16px 18px;
  font: 17px/1.8 var(--n-content-font); color: var(--n-text); outline: none; }
.rd-edit-body:focus { border-color: #b35c00; box-shadow: 0 0 0 3px rgba(179, 92, 0, .1); }
.rd-edit-bar { position: sticky; bottom: 0; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; padding: 12px 0; background: linear-gradient(transparent, #fff 30%); font-size: 12px; color: var(--n-faint); }
.rd-meta #edState.dirty { color: #b35c00; font-weight: 500; }
@media (max-width: 860px) {
  .rd-title-input { font-size: 26px; }
  .rd-mode { margin-top: 18px; }
}

/* 试用按钮下方的小字：试用时长 + 之后的价格 */
.rd-trial-note { font-size: 13px; color: var(--n-faint); margin: 10px 0 0; }
.rd-hero > p.rd-trial-note { font-size: 13px; color: var(--n-faint); margin: 10px auto 0; }
.rd-hero p.no-refund { font-size: 12px; color: var(--n-faint); margin: 10px auto 0; }

/* 导出：Markdown，可导入 Notion / FlowUs */
.rd-meta .rd-export { color: var(--n-faint); padding: 2px 6px; border-radius: 4px; }
.rd-meta .rd-export:hover { background: var(--n-hover); color: var(--n-text); }
.rd-export-all { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; margin-top: 14px; padding: 9px 8px 0; border-top: 1px solid var(--n-line); font-size: 13px; color: var(--n-faint); }
.rd-export-all span { margin-right: 4px; }
.rd-export-all a { color: var(--n-muted); padding: 2px 6px; border-radius: 4px; }
.rd-export-all a:hover { background: var(--n-hover); color: var(--n-text); }
.rd-side.collapsed .rd-export-all { display: none; }

/* 功能卡片：「一键欧路」占整行 */
.rd-feats .wide { grid-column: 1 / -1; }

/* ---------- 文件夹 ---------- */
.rd-folder { border-radius: 6px; }
.rd-frow { display: flex; align-items: center; border-radius: 6px; }
.rd-frow:hover { background: var(--n-hover); }
.rd-ftoggle { flex: 1; min-width: 0; display: flex; align-items: center; gap: 5px; border: 0; background: none; font: inherit; font-size: 14px; color: var(--n-text); padding: 7px 4px 7px 6px; cursor: pointer; text-align: left; }
.rd-ftoggle .caret { flex: none; width: 0; height: 0; margin: 0 4px 0 3px; border-left: 6px solid var(--n-muted); border-top: 4.5px solid transparent; border-bottom: 4.5px solid transparent; transition: transform .15s; }
.rd-folder.open .caret { transform: rotate(90deg); }
.rd-ftoggle .nm { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-weight: 500; }
.rd-ftoggle small { color: var(--n-faint); font-size: 12px; }
.rd-fmore { border: 0; background: none; color: var(--n-faint); font: 600 13px var(--n-font); padding: 4px 8px; border-radius: 4px; cursor: pointer; opacity: 0; }
.rd-frow:hover .rd-fmore, .rd-fmore:focus { opacity: 1; }
@media (hover: none) { .rd-fmore { opacity: 1; } }
.rd-fdocs { margin-left: 14px; padding-left: 6px; border-left: 1px solid var(--n-line); }
.rd-fdocs .empty { font-size: 12px; }
.rd-loose { font-size: 12px; color: var(--n-faint); padding: 12px 8px 4px; }
.rd-fname { display: flex; align-items: center; gap: 6px; padding: 4px 6px; }
.rd-fname input { flex: 1; min-width: 0; font: inherit; font-size: 14px; padding: 5px 8px; border: 1px solid #3b82f6; border-radius: 6px; outline: none; box-shadow: 0 0 0 3px rgba(59, 130, 246, .15); }
/* 拖动文章时，可以放下的位置高亮 */
.rd-side.dragging [data-drop] { border-radius: 6px; }
.rd-side.dragging div[data-drop="0"]:empty { min-height: 34px; border: 1px dashed var(--n-line); margin-top: 6px; }
[data-drop].drop-on { background: rgba(59, 130, 246, .1); box-shadow: inset 0 0 0 1.5px rgba(59, 130, 246, .5); }
.rd-fmenu { position: fixed; z-index: 50; background: #fff; border-radius: 8px; padding: 5px; min-width: 170px; box-shadow: 0 8px 26px rgba(15, 15, 15, .16), 0 0 0 1px rgba(15, 15, 15, .06); font-family: var(--n-font); }
.rd-fmenu > * { display: block; width: 100%; border: 0; background: none; font: inherit; font-size: 13.5px; color: var(--n-text); text-align: left; padding: 7px 10px; border-radius: 5px; cursor: pointer; }
.rd-fmenu > *:hover { background: var(--n-hover); }
.rd-fmenu .danger { color: var(--n-red); }
.rd-fsel { font: inherit; font-size: 13px; color: var(--n-muted); border: 1px solid var(--n-line); background: #fff; border-radius: 6px; padding: 2px 6px; max-width: 200px; cursor: pointer; }
.rd-fsel:hover { border-color: rgba(55, 53, 47, .25); color: var(--n-text); }
.rd-newrow { display: flex; gap: 10px; align-items: center; }
.rd-newrow input { flex: 1; min-width: 0; }
.rd-newrow .rd-fsel { font-size: 14px; padding: 8px 10px; }
@media (max-width: 860px) { .rd-side.collapsed .rd-list { display: none; } }

/* ---------- 会员分组：普通会员 / AI 会员 ---------- */
.rd-tier { display: flex; align-items: baseline; justify-content: center; gap: 10px; flex-wrap: wrap; margin: 30px 0 -18px; font-size: 14px; color: var(--n-muted); }
.rd-tier b { font-size: 16px; color: var(--n-text); }
.rd-tier.ai b { color: #5b3fc4; }
.rd-price.ai { border-color: rgba(108, 79, 214, .35); background: #faf8ff; }
.rd-price.ai:hover { border-color: #6c4fd6; box-shadow: 0 8px 24px rgba(108, 79, 214, .15); }
.rd-price.ai .pr b { color: #5b3fc4; }
.rd-upgrade { display: flex; align-items: center; justify-content: center; gap: 12px; flex-wrap: wrap; margin: 28px auto -16px; max-width: 560px; padding: 10px 14px;
  background: #f4f0ff; border: 1px solid rgba(108, 79, 214, .25); border-radius: 10px; font-size: 13.5px; color: var(--n-text); text-align: left; }
.rd-upgrade b { color: #5b3fc4; }
.rd-plans .rd-plan.ai, .rd-plan.ai { background: #faf8ff; }
.rd-plan.ai .p { color: #5b3fc4; }
.rd-plan.up { width: 100%; margin: 14px 0 4px; border-color: rgba(108, 79, 214, .45); }
.rd-price.ai .tag-best { background: #6c4fd6; }
.rd-tier-note { text-align: center; font-size: 11.5px; color: #7d68d8; margin: -8px 0 0; }

/* 新建：粘贴文章 / 上传电子书 两个标签 */
.rd-tabs { display: inline-flex; gap: 2px; padding: 3px; background: var(--n-gray-bg); border-radius: 9px; margin-bottom: 22px; }
.rd-tabs button { border: 0; background: none; font: inherit; font-size: 14px; color: var(--n-muted); padding: 6px 14px; border-radius: 7px; cursor: pointer; }
.rd-tabs button.on { background: #fff; color: var(--n-text); font-weight: 600; box-shadow: 0 1px 3px rgba(15, 15, 15, .12); }
#tabBook > p { color: var(--n-muted); font-size: 14px; margin: 0 0 18px; line-height: 1.7; }
#tabBook h1 { font-size: 28px; margin: 0 0 6px; }
.rd-drop { display: flex; flex-direction: column; align-items: center; gap: 4px; border: 2px dashed var(--n-line); border-radius: 12px; padding: 38px 16px; text-align: center; cursor: pointer; color: var(--n-muted); font-size: 14px; transition: border-color .15s, background .15s; }
.rd-drop:hover, .rd-drop.over { border-color: rgba(35, 131, 226, .6); background: #f5f9fe; }
.rd-drop[hidden] { display: none; }
.rd-drop b { color: var(--n-text); font-size: 16px; }
.rd-drop small { color: var(--n-faint); font-size: 12px; margin-top: 8px; }
.rd-drop-ico { font-size: 34px; }
.rd-bk-loading { color: var(--n-muted); font-size: 14px; padding: 20px 0; }
.rd-bk-preview { border: 1px solid var(--n-line); border-radius: 12px; padding: 16px; }
.rd-bk-info { color: var(--n-muted); font-size: 13px; margin: 10px 2px; }
.rd-bk-toc { background: var(--n-side); border-radius: 8px; padding: 10px 14px; font-size: 13px; color: var(--n-muted); line-height: 1.8; max-height: 260px; overflow: auto; }
.rd-bk-toc b { display: block; color: var(--n-text); margin-bottom: 2px; }
.rd-bk-toc .lv1 { padding-left: 1.2em; } .rd-bk-toc .lv2 { padding-left: 2.4em; } .rd-bk-toc .lv3 { padding-left: 3.6em; }
.rd-bk-toc .more { color: var(--n-faint); }
.rd-bk-sample div { color: var(--n-text); font-family: var(--n-content-font); line-height: 1.6; margin-bottom: 6px; }
.rd-bk-sample div.h { font-weight: 700; }
.rd-bk-hint { font-size: 12px; color: var(--n-faint); margin: 10px 2px 0; line-height: 1.6; }

/* 电子书阅读：顶部固定的章节条（📑 目录 · 当前章节 · ‹ 3 / 20 ›） */
.rd-bookbar { position: sticky; top: 52px; z-index: 15; display: flex; align-items: center; gap: 8px; margin: 0 -10px 18px; padding: 8px 10px; background: rgba(255, 255, 255, .94); backdrop-filter: blur(8px); border-bottom: 1px solid var(--n-line); }
.rd-bk-tocbtn { border: 1px solid var(--n-line); background: #fff; border-radius: 7px; padding: 5px 11px; font: inherit; font-size: 13px; color: var(--n-text); cursor: pointer; white-space: nowrap; }
.rd-bk-tocbtn:hover { background: var(--n-hover); }
.rd-bk-cur { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 13px; color: var(--n-muted); }
.rd-bk-num { font-size: 12px; color: var(--n-faint); white-space: nowrap; font-variant-numeric: tabular-nums; }
.rd-bk-arrow { border: 0; background: none; font-size: 20px; line-height: 1; width: 30px; height: 30px; border-radius: 6px; color: var(--n-muted); cursor: pointer; }
.rd-bk-arrow:hover:not(:disabled) { background: var(--n-hover); color: var(--n-text); }
.rd-bk-arrow:disabled { opacity: .3; cursor: default; }
.rd-toc { position: absolute; left: 10px; top: calc(100% + 6px); width: min(420px, calc(100vw - 32px)); max-height: min(70vh, 560px); display: flex; flex-direction: column; background: #fff; border-radius: 12px;
  box-shadow: 0 0 0 1px rgba(15,15,15,.05), 0 3px 6px rgba(15,15,15,.1), 0 9px 24px rgba(15,15,15,.2); overflow: hidden; }
.rd-toc[hidden] { display: none; }
.rd-toc-head { display: flex; align-items: center; gap: 8px; padding: 12px 14px 8px; border-bottom: 1px solid var(--n-line); font-size: 14px; }
.rd-toc-head span { color: var(--n-faint); font-size: 12px; flex: 1; }
.rd-toc-head button { border: 0; background: none; color: var(--n-faint); font-size: 14px; cursor: pointer; padding: 2px 6px; border-radius: 4px; }
.rd-toc-list { overflow-y: auto; padding: 6px; overscroll-behavior: contain; }
.rd-toc-list button { display: block; width: 100%; text-align: left; border: 0; background: none; font: inherit; font-size: 14px; color: var(--n-text); padding: 7px 10px; border-radius: 6px; cursor: pointer; line-height: 1.4; }
.rd-toc-list button:hover { background: var(--n-hover); }
.rd-toc-list .lv1 { padding-left: 26px; font-size: 13.5px; color: var(--n-muted); }
.rd-toc-list .lv2, .rd-toc-list .lv3, .rd-toc-list .lv4 { padding-left: 42px; font-size: 13px; color: var(--n-muted); }
.rd-toc-list button.on { background: #e8f1fd; color: #1f5fbf; font-weight: 600; }
.rd-book .rd-ch-title, .rd-book h3 { font-family: var(--n-font); }
.rd-book .rd-ch-title { font-size: 24px; margin: 6px 0 18px; }
.rd-book h3 { font-size: 19px; margin: 22px 0 12px; }
.rd-article [data-b] { scroll-margin-top: 72px; }
.rd-article.rd-book [data-b] { scroll-margin-top: 112px; }   /* 电子书上面还有固定的章节条 */
.rd-bknav { display: flex; justify-content: space-between; gap: 12px; margin-top: 40px; padding-top: 18px; border-top: 1px solid var(--n-line); }
.rd-bknav button { max-width: 48%; border: 1px solid var(--n-line); background: #fff; border-radius: 10px; padding: 10px 14px; font: inherit; font-size: 14px; color: var(--n-text); cursor: pointer; text-align: left; line-height: 1.4; }
.rd-bknav button.next { text-align: right; margin-left: auto; }
.rd-bknav button:hover { border-color: rgba(35, 131, 226, .6); }
.rd-bknav small { display: block; color: var(--n-faint); font-size: 12px; }
.rd-bk-end { color: var(--n-faint); font-size: 14px; margin-left: auto; align-self: center; }

/* 「已回到上次读到的位置」提示 */
.rd-toast { position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%); z-index: 70; display: flex; align-items: center; gap: 12px; background: rgba(37, 37, 37, .92); color: #fff; font-size: 14px; padding: 10px 12px 10px 16px; border-radius: 10px; box-shadow: 0 6px 20px rgba(0, 0, 0, .2); transition: opacity .6s; max-width: calc(100vw - 32px); }
.rd-toast.out { opacity: 0; }
.rd-toast button { border: 0; background: rgba(255, 255, 255, .16); color: #fff; font: inherit; font-size: 13px; padding: 4px 10px; border-radius: 6px; cursor: pointer; white-space: nowrap; }
@media (max-width: 860px) {
  .rd-bookbar { margin: 0 -16px 16px; padding: 8px 16px; }
  .rd-toc { left: 8px; }
}

/* 📚 推荐书库 */
.rd-libbtn { color: var(--n-text); font-weight: 600; }
.rd-libbtn.on { background: rgba(55, 53, 47, .08); }
.lib { padding: 36px 0 20px; }
.lib h1 { font-size: 30px; margin: 0 0 8px; }
.lib-lead { color: var(--n-muted); font-size: 15px; line-height: 1.7; margin: 0 0 18px; }
.lib-lock { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; background: #fdf6e7; border-radius: 10px; padding: 10px 14px; font-size: 14px; margin-bottom: 18px; }
.lib h2 { font-size: 17px; margin: 26px 0 12px; }
.lib-filter { display: flex; flex-wrap: wrap; gap: 6px; margin: 22px 0 4px; }
.lib-filter button { border: 1px solid var(--n-line); background: #fff; border-radius: 980px; padding: 5px 12px; font: inherit; font-size: 13px; color: var(--n-muted); cursor: pointer; }
.lib-filter button.on { border-color: #3554d1; color: #3554d1; background: #f2f5ff; font-weight: 600; }
.lib-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 14px; }
.lib-card { display: flex; flex-direction: column; border: 1px solid var(--n-line); border-radius: 12px; padding: 0 0 14px; background: #fff; color: var(--n-text); overflow: hidden; transition: box-shadow .15s, transform .15s; }
.lib-card:hover { box-shadow: 0 6px 18px rgba(15, 15, 15, .08); transform: translateY(-1px); }
.lib-top { padding: 14px 16px 12px; border-top: 4px solid var(--lc, #9b9a97); background: linear-gradient(var(--lbg, #f7f7f5), #fff); }
.lib-top b { display: block; font-size: 17px; line-height: 1.35; }
.lib-top i { display: block; font-family: var(--n-content-font); font-size: 13.5px; color: var(--n-muted); margin-top: 2px; }
.lib-top span { display: block; font-size: 12px; color: var(--n-faint); margin-top: 4px; }
.lib-tags { display: flex; flex-wrap: wrap; gap: 5px; padding: 0 16px; font-size: 11.5px; }
.lib-tags span { background: var(--n-gray-bg, #f1f1ef); color: var(--n-muted); border-radius: 4px; padding: 1px 6px; }
.lib-card p { flex: 1; margin: 10px 16px 12px; font-size: 13px; line-height: 1.7; color: var(--n-muted); }
.lib-go { margin: 0 16px; font-size: 13px; font-weight: 600; color: #3554d1; }
.lib-note { color: var(--n-faint); font-size: 12px; margin-top: 30px; }
/* 难度颜色：从浅绿到深红 */
.l1 { --lc: #4caf7a; --lbg: #eef8f2; } .l2 { --lc: #1d9e8f; --lbg: #ebf7f5; } .l3 { --lc: #378add; --lbg: #edf4fc; }
.l4 { --lc: #7f69d6; --lbg: #f3f0fc; } .l5 { --lc: #c9553a; --lbg: #fcefeb; }
.lib-level { font-weight: 600; }
.lib-tags .lib-level, .rd-meta .lib-level { color: var(--lc) !important; background: var(--lbg) !important; border-radius: 4px; padding: 1px 6px; }
.lib-h { color: var(--lc); }
.rd-back { display: inline-block; margin-top: 24px; font-size: 13px; color: var(--n-muted); }
.rd-back + .rd-title { margin-top: 10px; }
.rd-zh { display: block; font-size: 16px; font-weight: 500; color: var(--n-muted); margin-top: 4px; }