/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html, body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 16px;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.5;
}
ul, li {
    list-style: none;
}
a {
    text-decoration: none;
    color: #333;
    transition: color 0.3s ease;
}
a:hover {
    color: #0088ff;
}
img {
    display: block;
    max-width: 100%;
    height: auto;
    border: none;
}
button {
    border: none;
    background: none;
    cursor: pointer;
    transition: all 0.3s ease;
}
/* 布局容器 */
.wrap {
    width: 100%;
    max-width: 750px;
    min-width: 320px;
    margin: 0 auto;
    background-color: #fff;
    overflow: hidden;
    position: relative;
}
/* 头部导航 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    max-width: 750px;
    margin: 0 auto;
    height: 50px;
    background-color: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    z-index: 999;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 15px;
}
.header__logo img {
    height: 30px;
}
.header__menu {
    width: 30px;
    height: 30px;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
.menu__line {
    display: block;
    width: 22px;
    height: 2px;
    background-color: #333;
    margin: 2px 0;
    transition: all 0.3s ease;
}
.header__nav {
    position: fixed;
    top: 50px;
    right: 0;
    width: 200px;
    height: calc(100vh - 50px);
    background-color: #fff;
    box-shadow: -1px 0 5px rgba(0, 0, 0, 0.1);
    transform: translateX(100%);
    transition: transform 0.3s ease;
    z-index: 998;
}
.header__nav.show {
    transform: translateX(0);
}
.nav__list {
    padding: 20px 0;
}
.nav__item {
    border-bottom: 1px solid #f0f0f0;
}
.nav__link {
    display: block;
    padding: 0 25px;
    height: 50px;
    line-height: 50px;
    text-align: left;
    font-size: 16px;
}
.nav__link:hover {
    background-color: #f5f5f5;
}
/* 蒙版 */
.mask {
    position: fixed;
    top: 50px;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.3);
    z-index: 997;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}
.mask.show {
    opacity: 1;
    pointer-events: auto;
}
/* 主体内容 */
.content {
    width: 100%;
    padding-top: 50px;
}
/* Banner区域 */
.banner {
    position: relative;
    width: 100%;
    height: 400px;
    overflow: hidden;
}
.banner__bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
}
.banner__content {
    position: relative;
    z-index: 2;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #fff;
    text-align: center;
    padding: 0 20px;
}
.banner__title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 15px;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
}
.banner__desc {
    font-size: 18px;
    margin-bottom: 40px;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}
/* 按钮组样式 - 增加按钮间距 */
.banner__btn-group {
    display: flex;
    gap: 20px; /* 按钮间距，可调整 */
    align-items: center;
}
.banner__btn {
    width: 150px;
    height: 44px;
    background-color: #0088ff;
    color: #fff;
    border-radius: 22px;
    font-size: 16px;
    font-weight: 500;
    box-shadow: 0 3px 8px rgba(0, 136, 255, 0.3);
}
.banner__btn:hover {
    background-color: #0077ee;
    box-shadow: 0 4px 10px rgba(0, 136, 255, 0.4);
}
/* 功能展示区 */
.features {
    width: 100%;
    padding: 30px 15px;
}
.features__item {
    margin-bottom: 25px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.08);
    display: flex;
    align-items: center;
    padding: 15px;
}
.features__img {
    max-width: 40%;
    margin-right: 15px;
    border-radius: 8px;
}
.features__desc {
    flex: 1;
}
.features__title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
    color: #333;
}
.features__text {
    font-size: 14px;
    color: #666;
    line-height: 1.4;
}
/* 页脚 */
.footer {
    padding: 30px 15px 20px;
    background-color: #f8f8f8;
    color: #999;
    font-size: 12px;
    text-align: center;
}
.footer__contact {
    margin-bottom: 15px;
}
.footer__links {
    margin-bottom: 15px;
}
.footer__link {
    color: #666;
    margin: 0 8px;
}
.footer__info p {
    margin-bottom: 8px;
    line-height: 1.6;
}
/* 友情链接样式 */
.footer__friends {
    margin-bottom: 15px;
    padding: 0 10px;
}
.friends__title {
    font-size: 14px;
    color: #666;
    margin-bottom: 10px;
    text-align: center;
    font-weight: 600;
}
.friends__list {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
}
.friends__link {
    color: #999;
    font-size: 12px;
    padding: 2px 8px;
    border-radius: 4px;
    background-color: #f0f0f0;
    transition: all 0.3s ease;
}
.friends__link:hover {
    color: #0088ff;
    background-color: #e8f4ff;
}
/* 动画效果 */
.animated {
    animation-duration: 0.6s;
    animation-fill-mode: both;
}
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
.fadeInUp {
    animation-name: fadeInUp;
    animation-timing-function: ease-out;
}
.delay002 {
    animation-delay: 0.2s;
}
.delay003 {
    animation-delay: 0.3s;
}
.delay004 {
    animation-delay: 0.4s; /* 新增动画延迟 */
}
/* 响应式适配 */
@media (min-width: 768px) {
    .header__menu {
        display: none;
    }
    .header__nav {
        position: static;
        width: auto;
        height: auto;
        transform: translateX(0);
        box-shadow: none;
        background-color: transparent;
    }
    .nav__list {
        display: flex;
        padding: 0;
    }
    .nav__item {
        border-bottom: none;
        margin-left: 20px; /* 调整导航项间距，适配新增的联系我们 */
    }
    .nav__link {
        padding: 0;
        height: 50px;
        line-height: 50px;
    }
    .mask {
        display: none;
    }
    .banner {
        height: 500px;
    }
    .banner__title {
        font-size: 50px;
    }
    .banner__desc {
        font-size: 20px;
    }
    .features {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
        padding: 40px 20px;
    }
    .features__item {
        margin-bottom: 0;
        padding: 20px;
    }
    .features__img {
        max-width: 35%;
        margin-right: 20px;
    }
    .features__title {
        font-size: 19px;
    }
    .features__text {
        font-size: 15px;
    }
}
@media (max-width: 375px) {
    .banner {
        height: 350px;
    }
    .banner__title {
        font-size: 36px;
    }
    .banner__desc {
        font-size: 16px;
    }
    /* 移动端按钮垂直排列，增加间距 */
    .banner__btn-group {
        flex-direction: column;
        gap: 15px;
    }
    .banner__btn {
        width: 140px;
        height: 40px;
        font-size: 15px;
    }
    .features__item {
        flex-direction: column;
        text-align: center;
    }
    .features__img {
        max-width: 60%;
        margin-right: 0;
        margin-bottom: 12px;
    }
}
/* 菜单激活状态 */
.header__menu.active .menu__line:nth-child(1) {
    transform: rotate(45deg) translate(4px, 4px);
}
.header__menu.active .menu__line:nth-child(2) {
    opacity: 0;
}
.header__menu.active .menu__line:nth-child(3) {
    transform: rotate(-45deg) translate(4px, -4px);
}