body {
    height: auto;
    max-width: 1980px;
    margin: 0 auto;
}

.h-header {
    display: flex;
    justify-content: center;
    align-items: center;
    height: auto;
    font-size: 35px;
    background: linear-gradient(120deg, #7f8fa6 0%, #b2bec3 50%, #dff9fb 100%);
}

.x-nav {
    display: flex;
    padding-left: 400px;
    align-items: center;
    height: 40px;
    font-size: 20px;
    background-color: rgb(190, 125, 39);

}

.h-main {
    height: 350px;
    background: linear-gradient(135deg, #6a8caf 0%, #b5c6d6 100%);
    position: relative;
    overflow: hidden
}

.tu {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 0;
    transform: translateX(100%);
    transition: opacity 0.5s, transform 0.5s;
    z-index: 0;
}

.tu.active {
    opacity: 1;
    transform: translateX(0);
    z-index: 1;
}

.h-jianjie {
    background: #f8f8f8;
    border-radius: 12px;
    padding: 32px 28px;
    margin: 30px auto;
    max-width: 900px;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    font-size: 18px;
    line-height: 2.1;
    color: #333;
}

.jianjie-title {
    text-align: center;
    font-size: 28px;
    font-weight: bold;
    margin-bottom: 18px;
    letter-spacing: 4px;
    color: #2c3e50;
}

.jianjie-content p {
    text-indent: 2em;
    margin: 12px 0;
}

.h-footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px;
    font-size: 20px;
    height: 70px;
}