body {
    font-family: Verdana, sans-serif;
    background-color: #F5F5F5;
    margin: 0;
    padding: 0;
}

h1, h2, h3 {
    font-family: Georgia, serif;
    color: #4E0102;
}

h1 {
    text-align: center;
    margin-top: 20px;
}

h2 {
    border-top: solid 2px #4E0102;
    padding-top: 1em;
    margin-top: 20px;
}

h3 {
    margin-top: 15px;
}

p {
    line-height: 1.6;
    margin: 15px 0;
}

#navigation {
    font-family: Georgia, serif;
    font-size: 16px;
    border-top: solid 2px #4E0102;
    border-bottom: solid 2px #4E0102;
    text-align: center;
    background-color: #EFEFEF;
    padding: 10px 0;
    margin: 20px 0;
}

#navigation ul {
    padding: 0;
    margin: 0;
}

#navigation li {
    display: inline;
    list-style-type: none;
    margin: 0 10px;
}

a:link, a:visited, a:active {
    color: #17037A;
    text-decoration: none;
    font-weight: bold;
    transition: color 0.3s ease, text-decoration 0.3s ease;
}

a:hover {
    color: #FF4500;
    text-decoration: underline;
}

.current {
    color: #17037A;
    text-decoration: underline;
    font-weight: bold;
}

a[href="#top"] {
    display: block;
    text-align: right;
    margin-top: 10px;
    font-size: 14px;
}

a[href="#top"]:hover {
    color: #FF4500;
}

section {
    width: 80%;
    margin: 20px auto;
    background-color: #FFFFFF;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

@media (max-width: 600px) {
    section {
        width: 95%;
        padding: 15px;
    }

    #navigation li {
        display: block;
        margin: 5px 0;
    }

    a[href="#top"] {
        text-align: center;
    }
}
/* 🌙 暗黑模式优化 */
.dark-mode {
    background-color: #000;  /* 纯黑背景 */
    color: #FFF; /* 白色字体 */
    transition: background-color 0.3s, color 0.3s;
}

/* 标题变白 */
.dark-mode h1, 
.dark-mode h2, 
.dark-mode h3 {
    color: #FFF;
}

/* 导航栏变暗 */
.dark-mode #navigation {
    background-color: #111;  /* 变深 */
    border-top: solid 2px #333; /* 深色边框 */
    border-bottom: solid 2px #333;
}

/* 导航栏文字变白 */
.dark-mode #navigation a {
    color: #FFF;
}

.dark-mode #navigation a:hover {
    color: #BBB; /* 悬停时变灰 */
}

/* 主要内容区域背景变暗 */
.dark-mode section {
    background-color: #111;  /* 纯黑背景 */
    color: #FFF; /* 文字变白 */
    border-left: 4px solid #333; /* 深色边框 */
}

/* 所有链接变白 */
.dark-mode a {
    color: #FFF;
}

.dark-mode a:hover {
    color: #BBB; /* 悬停时变灰 */
}

/* 返回顶部按钮变暗 */
.dark-mode #backToTop {
    background-color: #333; /* 深灰色按钮 */
    color: white;
}

.dark-mode #backToTop:hover {
    background-color: #555; /* 悬停时变更亮的灰 */
}