/* 全局样式设置 */
body {
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    color: #ffffff;
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    overflow-x: hidden;
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(20, 20, 20, 0.9);
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.navbar a {
    color: #ffffff;
    margin: 0 15px;
    text-decoration: none;
    transition: color 0.3s ease;
    rel: "nofollow";
}

.navbar a:hover {
    color: #FF6F00;
}

/* 主容器样式 */
.container {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 20px;
    padding: 100px 40px 40px 40px; /* 上方留出导航栏空间 */
    max-width: 1200px;
    margin: 0 auto;
}

/* 主要内容区样式 */
.main-content {
    grid-column: 1 / 2;
}

/* 侧边栏样式 */
.sidebar {
    grid-column: 2 / 3;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

/* 文章样式 */
article {
    max-width: 800px;
    min-width: 500px;
    margin: 0 auto;
}

/* 标题样式 */
h2, h3, h4 {
    color: #ffffff;
    margin-top: 20px;
}

h2 {
    font-size: 2em;
    border-bottom: 2px solid #FF6F00;
    padding-bottom: 10px;
}

h3 {
    font-size: 1.75em;
    margin-top: 30px;
}

h4 {
    font-size: 1.5em;
    margin-top: 25px;
}

/* 段落样式 */
p {
    font-size: 16px;
    color: #d1d1d1;
    margin-bottom: 20px;
}

/* 强调文字样式 */
strong {
    color: #FF6F00;
}

/* 图片装饰样式 */
img.decorative {
    width: 320px;
    height: 320px;
    border-radius: 15px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

img.decorative:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 16px rgba(0,0,0,0.3);
    cursor: pointer;
}

/* 代码块样式 */
pre code {
    display: block;
    overflow: auto;
    padding: 20px;
    background: #1e1e1e;
    border-radius: 8px;
    font-family: 'Courier New', Courier, monospace;
    color: #d4d4d4;
    position: relative;
}

pre code::before {
    content: "CSS3 示例代码";
    position: absolute;
    top: 0;
    left: 0;
    background: #FF6F00;
    color: #ffffff;
    padding: 5px 10px;
    border-top-left-radius: 8px;
    border-top-right-radius: 8px;
    font-size: 14px;
}

/* 按钮样式 */
.button-primary {
    background-color: #FF6F00;
    color: #ffffff;
    padding: 12px 24px;
    border: none;
    border-radius: 4px;
    transition: background-color 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

.button-primary:hover {
    background-color: #e65c00;
}

/* 卡片样式 */
.card {
    background-color: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: 20px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    color: #333333;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 8px 12px rgba(0, 0, 0, 0.2);
}

/* 折叠区域样式 */
.collapsible {
    background-color: #2c5364;
    color: #ffffff;
    cursor: pointer;
    padding: 10px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 16px;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.collapsible:hover {
    background-color: #203a43;
}

.content {
    padding: 0 18px;
    display: none;
    overflow: hidden;
    background-color: #1e2a38;
    border-radius: 4px;
    margin-bottom: 10px;
}

/* 背景装饰线条 */
.decorative-line {
    height: 2px;
    background: linear-gradient(90deg, #FF6F00, #2c5364);
    margin: 20px 0;
    border: none;
    width: 100%;
    border-radius: 1px;
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .container {
        grid-template-columns: 1.5fr 1fr;
    }
}

@media (max-width: 992px) {
    .container {
        grid-template-columns: 1fr;
    }

    .sidebar {
        flex-direction: row;
        overflow-x: scroll;
    }

    img.decorative {
        width: 240px;
        height: 240px;
    }
}

@media (max-width: 768px) {
    h2 {
        font-size: 1.75em;
    }

    h3 {
        font-size: 1.5em;
    }

    h4 {
        font-size: 1.25em;
    }

    p {
        font-size: 15px;
    }
}

/* 提示信息样式 */
.notification {
    background-color: rgba(255, 111, 0, 0.9);
    color: #ffffff;
    padding: 20px;
    text-align: center;
    font-size: 18px;
    border-radius: 8px;
    margin: 20px 0;
}