* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft YaHei", sans-serif;
}
a {
    text-decoration: none;
    color: inherit;
}
ul {
    list-style: none;
}
html, body {
    overflow: visible;
    /* 禁止浏览器默认滚动样式干扰 */
    background-color: #fff;
}
.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

:root {
    --main: #52b8d9;
    --main-dark: #40a2c2;
    --dark: #1f2937;
    --light: #f0f7ff;
    --gray: #666;
    --white: #fff;
}

body {
    padding-top: 75px;
}

/* 核心修复：固定定位+强制背景色+最高层级，滚动绝不变色 */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 75px;
    background-color: #52b8d9 !important;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    z-index: 99999 !important;
    /* 禁止样式被继承/覆盖 */
    background-clip: padding-box;
}
.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 75px;
}
.logo {
    font-size: 22px;
    font-weight: bold;
    color: #fff;
}
.nav-menu {
    display: flex;
    gap: 35px;
}
.nav-menu a {
    font-size: 16px;
    color: #fff;
    position: relative;
    transition: 0.3s;
}
.nav-menu a:hover {
    color: #000;
}
.nav-menu a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 2px;
    background: #000;
    transition: 0.3s;
}
.nav-menu a:hover::after {
    width: 100%;
}

.banner {
    height: 500px;
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    color: var(--white);
    position: relative;
    z-index: 1;
}
.banner h1 {
    font-size: 48px;
    margin-bottom: 15px;
}
.banner p {
    font-size: 18px;
    margin-bottom: 30px;
    opacity: 0.95;
}

.page-banner {
    height: 300px;
    background: linear-gradient(rgba(0,0,0,0.4), rgba(0,0,0,0.4)), url('https://picsum.photos/id/1048/1920/1080') center/cover no-repeat;
    display: flex;
    align-items: center;
    color: var(--white);
    position: relative;
    z-index: 1;
}
.page-banner h1 {
    font-size: 36px;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--main);
    color: var(--white);
    border-radius: 4px;
    transition: 0.3s;
}
.btn:hover {
    background: var(--main-dark);
}

.section {
    padding: 70px 0;
}
.title {
    text-align: center;
    margin-bottom: 50px;
}
.title h2 {
    font-size: 30px;
    color: var(--dark);
    position: relative;
    display: inline-block;
    padding-bottom: 15px;
}
.title h2::after {
    content: '';
    width: 60px;
    height: 3px;
    background: var(--main);
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    bottom: 0;
}

/* 船公司LOGO轮播样式 */
.logo-swiper {
    overflow: hidden;
    position: relative;
}
.logo-wrap {
    display: flex;
    transition: transform 0.5s ease;
}
.logo-item {
    flex: 0 0 16.666%;
    padding: 15px;
    text-align: center;
}
.logo-item img {
    width: 100%;
    height: 80px;
    object-fit: contain;
    opacity: 0.8;
    transition: 0.3s;
}
.logo-item img:hover {
    opacity: 1;
}
.swiper-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 36px;
    height: 36px;
    background: rgba(82,184,217,0.8);
    color: #fff;
    border: none;
    border-radius: 50%;
    font-size: 18px;
    cursor: pointer;
    z-index: 10;
}
.prev-btn {
    left: 10px;
}
.next-btn {
    right: 10px;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}
.about-text p {
    color: var(--gray);
    line-height: 1.8;
    margin-bottom: 15px;
}

.service-row {
    display: grid;
    grid-template-columns: repeat(3,1fr);
    gap: 30px;
}
.service-card {
    padding: 30px;
    background: var(--light);
    border-radius: 8px;
    transition: 0.3s;
}
.service-card:hover {
    box-shadow: 0 5px 20px rgba(82,184,217,0.2);
    transform: translateY(-5px);
}
.service-card h3 {
    margin-bottom: 15px;
    color: var(--dark);
}
.service-card p {
    color: var(--gray);
    line-height: 1.7;
}

.route-list {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 20px;
}
.route-item {
    padding: 20px;
    background: var(--light);
    text-align: center;
    border-radius: 6px;
}

.contact-box {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}
.contact-info p {
    font-size: 16px;
    line-height: 2.2;
    color: var(--dark);
}
.contact-info strong {
    color: var(--main);
}

footer {
    background: var(--dark);
    color: var(--white);
    text-align: center;
    padding: 35px 0;
    margin-top: 40px;
}