/* ===== Reset & Base（与首页 styles.css 保持同一套设计变量） ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #6366F1;
    --primary-deep: #4F46E5;
    --accent: #F43F5E;
    --bg: #F7F8FF;
    --bg-alt: #EEF0FB;
    --text: #171923;
    --text-soft: #5B6072;
    --card-border: #E4E6F4;
    --radius-lg: 24px;
    /* 内容区分类强调色（卡片按类别区分主次） */
    --c-amber: #F59E0B;
    --c-sky: #0EA5E9;
    --c-rose: #F43F5E;
    --c-emerald: #10B981;
    --c-violet: #8B5CF6;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.75;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(247, 248, 255, 0.92);
    backdrop-filter: blur(12px);
    z-index: 1000;
    padding: 0.9rem 0;
    border-bottom: 1px solid rgba(228, 230, 244, 0.7);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--text);
    font-size: 1.4rem;
    font-weight: 800;
}

.logo-icon {
    display: inline-flex;
    align-items: center;
}

.logo-icon img {
    width: 30px;
    height: 30px;
    border-radius: 8px;
    display: block;
}

.footer-brand .logo-icon img {
    width: 24px;
    height: 24px;
    border-radius: 6px;
}

.hero-title-logo {
    width: 60px;
    height: 60px;
    border-radius: 15px;
    vertical-align: middle;
    margin-right: 0.6rem;
    box-shadow: 0 8px 20px rgba(99, 102, 241, 0.18);
}

/* 正文/标题中的品牌词：内联小 logo + 文字，不单独用纯文字呈现品牌 */
.brand {
    font-weight: 700;
    white-space: nowrap;
}

.brand img {
    width: 1.1em;
    height: 1.1em;
    border-radius: 0.24em;
    vertical-align: -0.16em;
    margin-right: 0.28em;
}

.logo-sub {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-soft);
    padding-left: 0.55rem;
    margin-left: 0.55rem;
    border-left: 1px solid var(--card-border);
}

.nav-links {
    display: flex;
    gap: 1.6rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-soft);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-deep);
}

.nav-actions {
    display: flex;
    gap: 0.8rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.6rem 1.3rem;
    border-radius: 50px;
    font-size: 0.94rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
    box-shadow: 0 8px 20px rgba(99, 102, 241, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 26px rgba(99, 102, 241, 0.45);
}

.btn-outline {
    background: transparent;
    border: 1.5px solid var(--primary);
    color: var(--primary-deep);
}

.btn-outline:hover {
    transform: translateY(-2px);
}

/* ===== 页头横幅 ===== */
.doc-hero {
    margin-top: 72px;
    padding: 2.4rem 0 1.6rem;
    background: linear-gradient(180deg, #EEF0FB 0%, var(--bg) 100%);
    border-bottom: 1px solid var(--card-border);
}

.doc-hero-inner,
.doc-layout,
.doc-foot {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.crumb {
    font-size: 0.85rem;
    color: var(--text-soft);
    margin-bottom: 0.9rem;
}

.crumb a {
    color: var(--text-soft);
    text-decoration: none;
}

.crumb a:hover {
    color: var(--primary-deep);
}

.crumb span {
    margin: 0 0.4rem;
    color: #B9BDD3;
}

.doc-hero h1 {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.doc-hero .hero-desc {
    color: var(--text-soft);
    font-size: 1rem;
    max-width: 780px;
    margin-top: 0.6rem;
}

.doc-hero .hero-desc strong {
    color: var(--text);
}

.index-hero-title {
    font-size: 2.6rem;
}

.index-hero-title .highlight {
    background: linear-gradient(120deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.hero-badge {
    display: inline-block;
    background: #fff;
    color: var(--primary-deep);
    border: 1px solid var(--card-border);
    padding: 0.3rem 0.9rem;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.meta-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-top: 1.2rem;
}

.chip {
    background: #fff;
    border: 1px solid var(--card-border);
    border-radius: 50px;
    padding: 0.28rem 0.9rem;
    font-size: 0.82rem;
    color: var(--text-soft);
}

.chip strong {
    color: var(--text);
    font-weight: 600;
}

/* ===== 主体布局 ===== */
.doc-layout {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 2.2rem;
    padding-top: 2.2rem;
    padding-bottom: 3rem;
    align-items: start;
}

.doc-side {
    position: sticky;
    top: 88px;
    max-height: calc(100vh - 110px);
    overflow-y: auto;
    background: #fff;
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 1.2rem 1rem;
}

.side-title {
    font-size: 0.86rem;
    font-weight: 700;
    color: var(--text-soft);
    letter-spacing: 0.5px;
    padding: 0 0.5rem 0.6rem;
}

.side-group + .side-group {
    margin-top: 1rem;
}

.side-group > span {
    display: block;
    font-size: 0.78rem;
    font-weight: 700;
    color: #9CA0B5;
    padding: 0.4rem 0.5rem;
}

.side-group a {
    display: flex;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-soft);
    text-decoration: none;
    padding: 0.35rem 0.7rem;
    border-radius: 10px;
}

.side-group a:hover {
    background: var(--bg-alt);
    color: var(--primary-deep);
}

.side-group a.active {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.12), rgba(139, 92, 246, 0.12));
    color: var(--primary-deep);
    font-weight: 600;
}

.side-group a i {
    font-style: normal;
    color: #B9BDD3;
    font-size: 0.82rem;
}

.side-group a.side-sub {
    margin-left: 1.1rem;
    padding-left: 0.6rem;
    font-size: 0.86rem;
    border-left: 1px dashed var(--card-border);
    border-radius: 0 10px 10px 0;
}

/* ===== 内容区 ===== */
.doc-main {
    background: #fff;
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 2.2rem 2.4rem;
    box-shadow: 0 10px 34px rgba(23, 25, 35, 0.05);
}

.block + .block {
    margin-top: 2rem;
}

.block-title {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    font-size: 1.22rem;
    font-weight: 800;
    margin-bottom: 0.9rem;
}

.block-title::before {
    content: '';
    width: 4px;
    height: 1.05rem;
    background: linear-gradient(90deg, var(--primary), #8B5CF6);
    border-radius: 4px;
}

.block p {
    color: var(--text-soft);
}

.block p + p {
    margin-top: 0.7rem;
}

/* 正文与步骤中的重点强调（主题色加粗，与注意框/结果框形成层次） */
.block p strong,
.block p b,
.steps li strong,
.path-list li strong,
.key-list li strong,
.note li strong,
.result p strong,
.qa-a strong {
    color: var(--primary-deep);
    font-weight: 700;
}

.key-list {
    list-style: none;
    margin-top: 0.8rem;
}

.key-list li {
    position: relative;
    padding-left: 1.2rem;
    color: var(--text-soft);
}

.key-list li + li {
    margin-top: 0.45rem;
}

.key-list li::before {
    content: '';
    position: absolute;
    left: 0.15rem;
    top: 0.72rem;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--primary);
}

/* 页面速览条：这是什么/什么时候用/前置条件 的紧凑形式 */
.meta-strip {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.8rem;
}

.meta-item {
    display: flex;
    gap: 0.6rem;
    align-items: flex-start;
    padding: 0.75rem 0.9rem;
    border-radius: 14px;
    background: var(--bg-alt);
    border: 1px solid var(--card-border);
}

.meta-ico {
    font-size: 1.05rem;
    line-height: 1.5;
}

.meta-k {
    display: block;
    font-size: 0.76rem;
    font-weight: 700;
    color: #9CA0B5;
    letter-spacing: 0.5px;
}

.meta-v {
    display: block;
    font-size: 0.86rem;
    line-height: 1.55;
    color: var(--text-soft);
}

/* 进入路径 */
.path-list {
    list-style: none;
    counter-reset: path;
}

.path-list li {
    counter-increment: path;
    position: relative;
    padding: 0.65rem 0.9rem 0.65rem 3rem;
    background: var(--bg-alt);
    border-radius: 12px;
    color: var(--text-soft);
}

.path-list li + li {
    margin-top: 0.5rem;
}

.path-list li::before {
    content: counter(path);
    position: absolute;
    left: 0.85rem;
    top: 0.62rem;
    width: 1.35rem;
    height: 1.35rem;
    border-radius: 50%;
    background: #fff;
    border: 1px solid var(--card-border);
    color: var(--primary-deep);
    font-size: 0.75rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 操作步骤 */
.steps {
    list-style: none;
    counter-reset: step;
}

.steps li {
    counter-increment: step;
    position: relative;
    padding: 0.7rem 0 0.7rem 3rem;
    color: var(--text-soft);
    border-bottom: 1px dashed var(--card-border);
}

.steps li:last-child {
    border-bottom: none;
}

.steps li::before {
    content: counter(step);
    position: absolute;
    left: 0;
    top: 0.7rem;
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
    font-size: 0.85rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 截图 */
.shot {
    margin: 0;
    background: var(--bg-alt);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    padding: 1.2rem;
    text-align: center;
}

.shot img {
    max-width: 100%;
    width: auto;
    border-radius: 18px;
    box-shadow: 0 12px 30px rgba(23, 25, 35, 0.12);
}

.shot figcaption {
    margin-top: 0.7rem;
    font-size: 0.85rem;
    color: var(--text-soft);
}

/* 一步一图：序号 + 短句 + 紧邻截图 */
.step {
    display: grid;
    grid-template-columns: 2rem 1fr;
    gap: 0 0.9rem;
    padding: 1rem 0;
    border-bottom: 1px dashed var(--card-border);
}

.step:last-child {
    border-bottom: none;
}

.step-no {
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
    font-size: 0.85rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}

.step-text {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text);
    line-height: 1.6;
}

.step-text b {
    color: var(--primary-deep);
}

.step-note {
    font-size: 0.85rem;
    color: var(--text-soft);
    margin-top: 0.15rem;
}

.step .shot {
    margin-top: 0.7rem;
}

.lead {
    font-size: 1.08rem;
    font-weight: 500;
    color: var(--text);
}

/* 重点提示 */
.highlight-box {
    display: flex;
    gap: 0.7rem;
    align-items: flex-start;
    margin-top: 0.9rem;
    padding: 0.85rem 1.1rem;
    border-radius: 14px;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(139, 92, 246, 0.1));
    border: 1px solid rgba(99, 102, 241, 0.28);
}

.highlight-box p {
    color: var(--primary-deep);
    font-weight: 600;
}

.hl-icon {
    font-size: 1.05rem;
    line-height: 1.5;
}

/* 小卡片（分类、模式、策略）：按 --mc 强调色区分主次 */
.mini-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 0.8rem;
    margin-top: 1rem;
}

.mini-card {
    --mc: var(--primary);
    --mc-soft: rgba(99, 102, 241, 0.12);
    background: #fff;
    border: 1px solid var(--card-border);
    border-top: 3px solid var(--mc);
    border-radius: 14px;
    padding: 0.95rem 1.05rem;
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    box-shadow: 0 4px 14px rgba(23, 25, 35, 0.04);
}

.mini-card.mc-amber { --mc: var(--c-amber); --mc-soft: rgba(245, 158, 11, 0.14); }
.mini-card.mc-sky { --mc: var(--c-sky); --mc-soft: rgba(14, 165, 233, 0.13); }
.mini-card.mc-rose { --mc: var(--c-rose); --mc-soft: rgba(244, 63, 94, 0.12); }
.mini-card.mc-emerald { --mc: var(--c-emerald); --mc-soft: rgba(16, 185, 129, 0.13); }
.mini-card.mc-violet { --mc: var(--c-violet); --mc-soft: rgba(139, 92, 246, 0.13); }

.mini-icon {
    width: 2.3rem;
    height: 2.3rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
    background: var(--mc-soft);
    font-size: 1.2rem;
    margin-bottom: 0.2rem;
}

.mini-card strong {
    font-size: 0.98rem;
    color: var(--text);
}

.mini-desc {
    font-size: 0.84rem;
    color: var(--text-soft);
}

/* 手势卡（学习页滑动评分） */
.gesture-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 0.8rem;
}

.gesture-item {
    text-align: center;
    padding: 1rem 0.8rem;
    border-radius: 14px;
    background: #fff;
    border: 1px solid var(--card-border);
    box-shadow: 0 6px 16px rgba(23, 25, 35, 0.05);
}

.gesture-arrow {
    display: block;
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1.2;
}

.gesture-item strong {
    display: block;
    margin-top: 0.25rem;
}

/* 标签行 */
.tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.tag {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(139, 92, 246, 0.1));
    border: 1px solid rgba(99, 102, 241, 0.25);
    color: var(--primary-deep);
    border-radius: 50px;
    padding: 0.3rem 0.9rem;
    font-size: 0.85rem;
    font-weight: 600;
}

/* 问答（FAQ） */
.qa-item {
    padding: 0.9rem 1rem;
    border-radius: 14px;
    background: var(--bg-alt);
}

.qa-item + .qa-item {
    margin-top: 0.6rem;
}

.qa-q {
    font-weight: 700;
    color: var(--text);
}

.qa-a {
    color: var(--text-soft);
    font-size: 0.94rem;
    margin-top: 0.2rem;
}

/* 正文中的跳转链接：主题色加粗，与灰色说明文字区分主次 */
.block p a,
.path-list a,
.qa-a a,
.vs-card li a {
    color: var(--primary-deep);
    font-weight: 600;
    text-decoration: none;
}

.block p a:hover,
.path-list a:hover,
.qa-a a:hover,
.vs-card li a:hover {
    text-decoration: underline;
}

/* 两列表格的键列 */
.doc-table td.col-key {
    width: 32%;
    font-weight: 600;
    color: var(--text);
    background: #FBFCFF;
}

/* 注意事项 / 结果 */
.note {
    border-radius: 14px;
    padding: 1rem 1.2rem;
    background: #FFF7ED;
    border: 1px solid #FDE3C4;
}

.note li {
    color: #8A5A20;
}

.result {
    border-radius: 14px;
    padding: 1rem 1.2rem;
    background: #EEF2FF;
    border: 1px solid #D9DEFB;
}

.result p {
    color: #3B3F73;
}

.note ul,
.result ul {
    list-style: none;
}

.note li + li,
.result li + li {
    margin-top: 0.45rem;
}

/* 表格 */
.doc-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.94rem;
}

.doc-table th,
.doc-table td {
    border: 1px solid var(--card-border);
    padding: 0.65rem 0.9rem;
    text-align: left;
    vertical-align: top;
}

.doc-table th {
    background: var(--bg-alt);
    font-weight: 700;
}

.doc-table td {
    color: var(--text-soft);
}

/* 目录卡片 */
.cat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 1rem;
}

.cat-card {
    display: block;
    text-decoration: none;
    background: #fff;
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.1rem 1.2rem;
    transition: transform 0.25s, box-shadow 0.25s, border-color 0.25s;
}

.cat-card:hover {
    transform: translateY(-3px);
    border-color: rgba(99, 102, 241, 0.5);
    box-shadow: 0 12px 26px rgba(99, 102, 241, 0.14);
}

.cat-card .cat-no {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.1rem;
    height: 2.1rem;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.14), rgba(139, 92, 246, 0.14));
    color: var(--primary-deep);
    font-size: 0.82rem;
    font-weight: 700;
    transition: background 0.25s, color 0.25s;
}

.cat-card:hover .cat-no {
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
}

.cat-card h3 {
    font-size: 1.02rem;
    margin: 0.3rem 0 0.35rem;
    color: var(--text);
}

.cat-card p {
    font-size: 0.86rem;
    color: var(--text-soft);
}

/* 上下页 */
.pager {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

.pager a {
    flex: 1;
    text-decoration: none;
    background: #fff;
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 0.9rem 1.1rem;
    color: var(--text-soft);
    font-size: 0.9rem;
    transition: border-color 0.2s, transform 0.2s;
}

.pager a:hover {
    border-color: rgba(99, 102, 241, 0.5);
    transform: translateY(-2px);
}

.pager a b {
    display: block;
    color: var(--text);
    font-size: 1rem;
    margin-top: 0.15rem;
}

.pager .pager-next {
    text-align: right;
}

.pager .pager-empty {
    flex: 1;
    visibility: hidden;
}

/* ===== 流程条：按顺序走的步骤 ===== */
.flow {
    display: flex;
    flex-wrap: wrap;
}

.flow-step {
    position: relative;
    flex: 1 1 132px;
    background: var(--bg-alt);
    border: 1px solid var(--card-border);
    border-radius: 14px;
    padding: 0.8rem 0.9rem;
}

.flow-step + .flow-step {
    margin-left: 1.5rem;
}

.flow-step::before {
    content: '→';
    position: absolute;
    left: -1.15rem;
    top: 50%;
    transform: translateY(-50%);
    color: #B9BDD3;
    font-weight: 700;
}

.flow-step:first-child::before {
    content: none;
}

.flow-no {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 1.25rem;
    height: 1.25rem;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
    font-size: 0.72rem;
    font-weight: 700;
    margin-bottom: 0.3rem;
}

.flow-step strong {
    display: block;
    font-size: 0.95rem;
}

.flow-hint {
    display: block;
    font-size: 0.82rem;
    color: var(--text-soft);
}

/* ===== 对照卡：该这样 / 别这样（--vs 变量区分语义色） ===== */
.vs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.vs-card {
    --vs: #10B981;
    --vs-deep: #15803D;
    --vs-line: #C3E9D0;
    --vs-tint: #F0FDF4;
    --vs-chip: #DCFCE7;
    position: relative;
    border-radius: 16px;
    padding: 1.1rem 1.2rem 1.15rem;
    border: 1px solid var(--vs-line);
    background: linear-gradient(180deg, var(--vs-tint) 0%, #fff 55%);
    box-shadow: 0 4px 14px rgba(23, 25, 35, 0.04);
    overflow: hidden;
}

.vs-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: var(--vs);
}

.vs-dont {
    --vs: #F43F5E;
    --vs-deep: #BE123C;
    --vs-line: #FBD3D9;
    --vs-tint: #FFF1F2;
    --vs-chip: #FFE4E6;
}

.vs-head {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.28rem 0.8rem;
    border-radius: 50px;
    background: var(--vs-chip);
    color: var(--vs-deep);
    font-size: 0.9rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
}

.vs-card ul {
    list-style: none;
}

.vs-card li {
    position: relative;
    padding-left: 1.65rem;
    font-size: 0.9rem;
    line-height: 1.7;
    color: var(--text);
}

.vs-card li + li {
    margin-top: 0.45rem;
}

.vs-card li::before {
    position: absolute;
    left: 0;
    top: 0.26rem;
    width: 1.15rem;
    height: 1.15rem;
    border-radius: 50%;
    background: var(--vs-chip);
    color: var(--vs-deep);
    font-size: 0.7rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}

.vs-do li::before {
    content: '✓';
}

.vs-dont li::before {
    content: '✕';
}

.vs-card li b,
.vs-card li strong {
    color: var(--vs-deep);
    font-weight: 700;
}

/* ===== 间隔图：条形长度表达复习间隔 ===== */
.interval {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.iv-row {
    display: grid;
    grid-template-columns: 3.4rem 1fr 7rem;
    align-items: center;
    gap: 0.7rem;
}

.iv-label {
    font-size: 0.9rem;
    font-weight: 700;
}

.iv-track {
    height: 0.85rem;
    background: var(--bg-alt);
    border-radius: 50px;
    overflow: hidden;
}

.iv-bar {
    display: block;
    height: 100%;
    width: var(--w);
    border-radius: 50px;
    background: linear-gradient(90deg, var(--primary), #8B5CF6);
}

.iv-val {
    font-size: 0.84rem;
    color: var(--text-soft);
    text-align: right;
}

/* ===== CSS 界面示意（不依赖截图） ===== */
.mock-row {
    display: flex;
    gap: 1.4rem;
    align-items: center;
    flex-wrap: wrap;
}

.mock-cap {
    flex: 1 1 220px;
    font-size: 0.9rem;
    color: var(--text-soft);
}

.mock-row .interval {
    flex: 1 1 260px;
}

/* 手机卡面 */
.mock-phone {
    width: 186px;
    flex: none;
    background: #171923;
    border-radius: 26px;
    padding: 0.5rem;
    box-shadow: 0 14px 30px rgba(23, 25, 35, 0.22);
}

.mock-screen {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    min-height: 240px;
    padding: 0.85rem 0.7rem;
    background: #fff;
    border-radius: 20px;
}

.mock-face {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.7rem;
    border: 1px dashed var(--card-border);
    border-radius: 14px;
    background: var(--bg-alt);
    font-size: 0.92rem;
    font-weight: 700;
    text-align: center;
}

.mock-face.is-back {
    border-style: solid;
    border-color: rgba(99, 102, 241, 0.35);
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.12), rgba(139, 92, 246, 0.12));
}

.mock-flip {
    text-align: center;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--primary);
}

/* 卡包结构树 */
.mock-tree {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
    flex: none;
    width: 260px;
}

.tree-root {
    padding: 0.45rem 1rem;
    border-radius: 50px;
    background: linear-gradient(135deg, var(--primary), #8B5CF6);
    color: #fff;
    font-size: 0.95rem;
    font-weight: 700;
    text-align: center;
}

.tree-kids {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.4rem;
    margin-left: 1.1rem;
    padding-left: 0.8rem;
    border-left: 2px solid var(--card-border);
}

.tree-leaf {
    padding: 0.42rem 0.7rem;
    border: 1px solid var(--card-border);
    border-radius: 12px;
    background: var(--bg-alt);
    font-size: 0.86rem;
    color: var(--text-soft);
}

/* 一条笔记裂变成多张卡 */
.mock-split {
    display: flex;
    gap: 0.8rem;
    align-items: center;
    flex-wrap: wrap;
}

.split-src {
    flex: 1 1 180px;
    padding: 0.8rem 0.9rem;
    border: 1px dashed var(--card-border);
    border-radius: 14px;
    background: var(--bg-alt);
    font-size: 0.9rem;
    font-weight: 600;
    text-align: center;
}

.split-arrow {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary);
}

.split-out {
    display: flex;
    flex: 1 1 240px;
    flex-direction: column;
    gap: 0.4rem;
}

.split-card {
    padding: 0.45rem 0.8rem;
    border: 1px solid rgba(99, 102, 241, 0.35);
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.12), rgba(139, 92, 246, 0.12));
    font-size: 0.86rem;
    font-weight: 600;
    color: var(--primary-deep);
}

/* ===== 页脚 ===== */
.footer {
    padding: 2.6rem 0;
    background: #F0F1FA;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: center;
}

.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 1.1rem;
}

.footer-note {
    color: var(--text-soft);
    font-size: 0.88rem;
}

.footer p:last-child {
    color: #9CA0B5;
    font-size: 0.82rem;
}

.footer-beian {
    margin-left: 0.9rem;
    color: inherit;
    text-decoration: none;
}

.footer-beian:hover {
    text-decoration: underline;
}

/* ===== 响应式 ===== */
@media (max-width: 980px) {
    .nav-links {
        display: none;
    }

    .doc-layout {
        grid-template-columns: 1fr;
    }

    .doc-side {
        position: static;
        max-height: none;
    }

    .doc-main {
        padding: 1.6rem 1.3rem;
    }

    .doc-hero h1 {
        font-size: 1.6rem;
    }

    .index-hero-title {
        font-size: 2rem;
    }

    .hero-title-logo {
        width: 44px;
        height: 44px;
        border-radius: 11px;
        margin-right: 0.4rem;
    }

    .pager {
        flex-direction: column;
    }

    .pager .pager-next {
        text-align: left;
    }

    .pager .pager-empty {
        display: none;
    }

    .flow {
        flex-direction: column;
    }

    .meta-strip {
        grid-template-columns: 1fr;
    }

    .flow-step + .flow-step {
        margin-left: 0;
    }

    .flow-step::before {
        content: none;
    }

    .iv-row {
        grid-template-columns: 3.2rem 1fr 5.6rem;
        gap: 0.5rem;
    }

    .mock-phone,
    .mock-tree {
        width: 100%;
    }
}

/* 临时隐藏顶部「立即下载」按钮；恢复时删掉下面这条规则即可 */
.nav-actions {
    display: none;
}