body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f4f7f6;
    color: #333;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 1000px; /* 适当加宽以容纳更多内容 */
    margin: 30px auto;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    padding: 25px 35px;
}

h1 {
    color: #2c3e50;
    text-align: center;
    margin-bottom: 15px;
    border-bottom: 2px solid #e0e0e0;
    padding-bottom: 10px;
}

h2 {
    color: #16a085;
    margin-top: 35px;
    margin-bottom: 15px;
    padding-bottom: 5px;
    border-bottom: 1px solid #1abc9c;
}

h3 {
    color: #2980b9;
    margin-top: 15px;
    margin-bottom: 8px;
    font-size: 1.1em;
}

h4 {
    color: #34495e;
    margin-top: 10px;
    margin-bottom: 5px;
    font-size: 1em;
    text-align: center;
}


p {
    margin-bottom: 12px;
}

ul {
    padding-left: 20px;
    margin-bottom: 15px;
}

li {
    margin-bottom: 6px;
}

.back-link {
    display: inline-block;
    margin-bottom: 25px;
    color: #3498db;
    text-decoration: none;
    padding: 8px 15px;
    border: 1px solid #3498db;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
}

.back-link:hover {
    background-color: #3498db;
    color: #fff;
}

.section {
    margin-bottom: 40px;
    padding-bottom: 20px;
    border-bottom: 1px dashed #ccc;
}
.section:last-child {
    border-bottom: none;
}

.subsystem-container, .component-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); /* 响应式网格布局 */
    gap: 20px; /* 网格间距 */
    margin-top: 20px;
}

.subsystem, .component {
    background-color: #fdfdfd;
    border: 1px solid #eee;
    border-radius: 6px;
    padding: 15px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    transition: transform 0.2s ease-in-out;
}
.subsystem:hover, .component:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.08);
}

.subsystem img, .component img {
    max-width: 80px; /* 限制图片大小 */
    height: auto;
    margin-bottom: 10px;
    display: block;
    margin-left: auto;
    margin-right: auto;
}

.subsystem p, .component p {
    font-size: 0.9em;
    color: #555;
    text-align: left; /* 组件描述左对齐 */
}

.wiring-standards {
    display: flex;
    justify-content: space-around;
    margin-top: 20px;
    background-color: #f9f9f9;
    padding: 20px;
    border-radius: 5px;
}

.wiring-standards h4 {
    text-align: center;
    margin-bottom: 10px;
}

.wiring-standards ol {
    list-style: none;
    padding: 0;
    margin: 0;
}

.wiring-standards li {
    margin-bottom: 5px;
    font-family: Consolas, Monaco, monospace;
    display: flex;
    align-items: center;
}

.wire {
    display: inline-block;
    width: 15px;
    height: 15px;
    border: 1px solid #ccc;
    margin-right: 8px;
    border-radius: 3px;
}

/* 线缆颜色 */
.wire.orange-white { background: linear-gradient(to right, white 50%, #f39c12 50%); }
.wire.orange { background-color: #f39c12; }
.wire.green-white { background: linear-gradient(to right, white 50%, #2ecc71 50%); }
.wire.green { background-color: #2ecc71; }
.wire.blue-white { background: linear-gradient(to right, white 50%, #3498db 50%); }
.wire.blue { background-color: #3498db; }
.wire.brown-white { background: linear-gradient(to right, white 50%, #a0522d 50%); }
.wire.brown { background-color: #a0522d; }

/* 占位图片样式，如果图片不存在 */
img[alt] {
    background-color: #eee;
    border: 1px dashed #ccc;
    color: #888;
    text-align: center;
    line-height: 60px; /* 调整以匹配图片高度 */
    width: 80px;
    height: 60px;
    font-size: 0.8em;
}