body {
    font-family: "SimSun", "STSong", serif;
    background-color: #f8f9fa;
    color: #333;
    line-height: 1.6;
}
.chapter-header {
    background-color: #2c3e50;
    color: white;
    padding: 2.5rem 0;
    margin-bottom: 2rem;
    border-bottom: 5px solid #c19a6b;
}
.chapter-title {
    font-size: 2.5rem;
    font-weight: bold;
    text-align: center;
    margin-bottom: 0.5rem;
}
.chapter-subtitle {
    font-size: 1.2rem;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    color: #e0e0e0;
}
.content-section {
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    padding: .5rem .8rem;
    margin-bottom: 1rem;
}
.section-title {
    font-size: 1.8rem;
    color: #2c3e50;
    border-bottom: 3px solid #c19a6b;
    padding-bottom: 0.8rem;
    margin-bottom: 1.5rem;
    text-align: center;
}
.original-text {
    font-size: 1.2rem;
    line-height: 2;
    text-align: justify;
    margin-bottom: 2rem;
}
.original-text p {
    margin-bottom: 1.5rem;
    text-indent: 2em;
}
.translation-text {
    font-size: 1.1rem;
    line-height: 1.8;
    text-align: justify;
    color: #555;
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 6px;
    border-left: 4px solid #c19a6b;
}
.translation-text p {
    margin-bottom: 1.2rem;
}
.verse-item {
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px dashed #e9ecef;
}
.verse-number {
    display: inline-block;
    background-color: #2c3e50;
    color: white;
    width: 30px;
    height: 30px;
    line-height: 30px;
    text-align: center;
    border-radius: 50%;
    margin-right: 10px;
    font-size: 0.9rem;
}
.verse-title {
    color: #2c3e50;
    font-weight: bold;
    margin-bottom: 0.8rem;
}
.navigation-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 2px solid #e9ecef;
}
.nav-btn {
    padding: 0.8rem 1.5rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
}
.nav-btn-prev {
    background-color: #f8f9fa;
    color: #2c3e50;
    border: 2px solid #2c3e50;
}
.nav-btn-prev:hover {
    background-color: #2c3e50;
    color: white;
}
.nav-btn-next {
    background-color: #2c3e50;
    color: white;
    border: 2px solid #2c3e50;
}
.nav-btn-next:hover {
    background-color: #c19a6b;
    border-color: #c19a6b;
}
.nav-btn-home {
    background-color: #c19a6b;
    color: white;
    border: 2px solid #c19a6b;
}
.nav-btn-home:hover {
    background-color: #a87c52;
    border-color: #a87c52;
}
.annotation {
    font-size: 0.9rem;
    color: #6c757d;
    font-style: italic;
    margin-top: 0.5rem;
    padding-left: 1rem;
    border-left: 2px solid #dee2e6;
}
.highlight {
    background-color: #fffacd;
    padding: 2px 4px;
    border-radius: 3px;
}
.copyright{
    margin-bottom: 20px;
}
@media (max-width: 768px) {
    .chapter-title {
        font-size: 2rem;
    }
    .original-text {
        font-size: 1.1rem;
    }
    .navigation-buttons {
        flex-direction: column;
        gap: 1rem;
    }
    .nav-btn {
        justify-content: center;
    }
}
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    display: none;          /* 默认隐藏 */
    width: 50px;
    height: 50px;
    background-color: #2c3e50;
    color: white;
    border-radius: 50%;
    text-align: center;
    line-height: 50px;
    z-index: 999;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
    text-decoration: none;
    opacity: 0.8;
}
.back-to-top:hover {
    background-color: #c19a6b;
    color: white;
    transform: translateY(-3px);
}
.back-to-top svg {
    width: 24px;
    height: 24px;
    vertical-align: middle;
    margin-top: -3px;
}
@media (max-width: 768px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 45px;
        height: 45px;
        line-height: 45px;
        opacity: 0.8;
    }
    .back-to-top svg {
        width: 20px;
        height: 20px;
    }
}