:root {
            --read-bg: #EFEDE9; /* 柔和陈年纸色 */
            --read-text: #3C3F38; /* 深苔绿灰 */
            --brand-green: #5B705B;
            --brand-light: #E1E6E1;
            --border: #DEDAD4;
        }

        body {
            margin: 0;
            background-color: var(--read-bg);
            font-family: "PingFang SC", "STHeiti", serif;
            color: var(--read-text);
            line-height: 1.85;
            padding-top: 60px; /* 留出顶部栏空间 */
        }

        .app-wrapper {
            max-width: 500px;
            margin: 0 auto;
            min-height: 100vh;
        }

        /* 常驻顶部导航 */
        .read-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            height: 54px;
            background: rgba(239, 237, 233, 0.95); /* 略带透明 */
            backdrop-filter: blur(5px);
            display: flex;
            align-items: center;
            padding: 0 10px;
            z-index: 100;
            border-bottom: 1px solid var(--border);
        }

        .back-btn {
            width: 44px;
            height: 44px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 32px;
            text-decoration: none;
            color: var(--brand-green);
            font-weight: 300;
        }

        .top-info {
            flex: 1;
            text-align: center;
            font-size: 14px;
            color: var(--brand-green);
            font-weight: 500;
            margin-right: 44px;
        }

        /* 阅读正文 */
        .read-body {
            padding: 20px 22px;
        }

        .chapter-title {
            font-size: 24px;
            font-weight: bold;
            color: #2D302B;
            margin-bottom: 35px;
            letter-spacing: 1px;
        }

        .content-p {
            font-size: 19px;
            margin-bottom: 25px;
            text-indent: 2em;
            text-align: justify;
        }

        /* 底部导航按钮 */
        .read-footer-nav {
            padding: 30px 20px;
            display: flex;
            gap: 12px;
        }

        .nav-link-btn {
            flex: 1;
            height: 44px;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--brand-light);
            color: var(--brand-green);
            border-radius: 8px;
            text-decoration: none;
            font-size: 15px;
            font-weight: 500;
        }

        /* 底部推荐板块 */
        .rec-section {
            margin: 20px;
            padding: 20px;
            background: #F4F2EE;
            border-radius: 12px;
            border: 1px solid var(--border);
        }

        .rec-title {
            font-size: 16px;
            font-weight: bold;
            color: var(--brand-green);
            margin-bottom: 15px;
            border-left: 3px solid var(--brand-green);
            padding-left: 10px;
        }

        .rec-item {
            display: flex;
            justify-content: space-between;
            padding: 12px 0;
            border-bottom: 1px solid var(--border);
            text-decoration: none;
            color: inherit;
            font-size: 15px;
        }

        .rec-item:last-child {
            border-bottom: none;
        }

        /* --- 侧边目录弹窗 --- */
        .side-mask {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.4);
            display: none;
            z-index: 200;
        }

        .side-mask.active {
            display: block;
        }

        /* --- 侧边目录优化后 --- */
        .side-catalog {
            position: fixed;
            top: 0;
            right: -85%;
            width: 85%;
            height: 100%;
            background: var(--read-bg);
            z-index: 201;
            transition: transform 0.3s ease, box-shadow 0.3s ease; /* 增加阴影过渡 */
            /* 初始状态下投影设为透明，解决边缘漏光问题 */
            box-shadow: -5px 0 20px rgba(0, 0, 0, 0);
            display: flex;
            flex-direction: column;
            visibility: hidden; /* 初始不可见，彻底解决边框露出的问题 */
        }

        .side-catalog.active {
            transform: translateX(-100%);
            /* 激活时显示投影 */
            box-shadow: -5px 0 20px rgba(0, 0, 0, 0.1);
            visibility: visible;
        }

        .cat-head {
            padding: 20px;
            border-bottom: 1px solid var(--border);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: bold;
            color: var(--brand-green);
        }

        .cat-scroll {
            flex: 1;
            overflow-y: auto;
            padding: 10px 20px;
        }

        .cat-row {
            padding: 18px 0;
            border-bottom: 1px solid var(--border);
            display: flex;
            text-decoration: none;
            color: var(--read-text);
            font-size: 16px;
        }

        .cat-row.active {
            color: var(--brand-green);
            font-weight: bold;
        }

        .cat-num {
            width: 60px;
            font-family: Constantia, Georgia, serif;
        }

        .close-cat-btn {
            font-size: 14px;
            cursor: pointer;
            color: var(--text-muted);
        }

        .read-body {
            font-size: 18px;
        }

        .read-body p {
            margin: 2rem 0;
            line-height: 150%;
            text-indent: 2em;
            margin-block-start: 0.7em !important;
            margin-block-end: 0.7em !important;
            font-family: Helvetica, Droidsansfallback, Droid Sans, Retina, arial, PingFangTC, "Microsoft JhengHei", Arial, sans-serif, "PingFangTC", "Microsoft JhengHei", Arial, sans-serif !important;
        }