/* 纸质书容器美化 */
.paper-book {
    background-color: #f4f1ea; /* 经典的米色纸张底色 */
    color: #3e3a36; /* 深咖啡色文字，比纯黑更柔和 */
    padding: 25px 20px;
    border: 1px solid #dcd3c1;
    border-radius: 3px;
    /* 模拟纸张边缘阴影和微弱的立体感 */
    box-shadow: inset 0 0 60px rgba(0,0,0,0.02), 2px 2px 8px rgba(0,0,0,0.05);
    /* 字体优先使用衬线体，更有书卷气 */
    font-family: "Noto Serif SC", "Source Han Serif SC", "SimSun", "STSong", serif;
    line-height: 1.8; /* 增加行高，提升阅读舒适度 */
    letter-spacing: 0.5px;
    position: relative;
    overflow: hidden;
}

/* 模拟书页左侧的装订线阴影 */
.paper-book::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    width: 15px;
    background: linear-gradient(to right, rgba(0,0,0,0.05) 0%, rgba(0,0,0,0) 100%);
    pointer-events: none;
}

/* 状态栏折叠框美化 */
.paper-book details {
    margin-bottom: 15px;
    border-bottom: 1px dashed #dcd3c1;
    padding-bottom: 10px;
}

.paper-book summary {
    font-weight: bold;
    cursor: pointer;
    color: #8c7e6a; /* 稍微浅一点的棕色 */
    list-style: none;
}

.paper-book summary::before {
    content: "🔖 "; /* 加入一个小书签图标 */
}

/* 正文文本样式 */
.paper-book text {
    display: block;
    margin-top: 15px;
    text-indent: 2em; /* 首行缩进，这才是写书的灵魂 */
}

/* 记忆栏等区块美化 */
.paper-book .memory-zone {
    font-size: 0.9em;
    background: rgba(255,255,255,0.3);
    padding: 10px;
    border-radius: 5px;
    margin-top: 20px;
}