/* ==========================================================
 * 煜通百泰 首页样式 index.css
 * 包含：Banner 轮播 / 关于我们 / 产品中心 / 技术服务 / 新闻中心
 * 依赖：base.css（提供主题变量与公共组件）
 * 单位说明：1rem = 16px（@1920px 设计稿，由 html{font-size:0.83328vw} 计算）
 * ========================================================== */

/* ==================== 第 1 屏：Banner 满屏轮播 ==================== */
.banner-section { width: 100%; overflow: hidden; }
.banner-swiper { width: 100%; }
.banner-slide {
    height: 100vh;
    min-height: 37.5rem;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    display: flex;
    align-items: center;
}
.banner-content { max-width: 60%; }

/* 徽章（小标签） */
.banner-badge {
    display: inline-flex;
    align-items: center;
    padding: 0.5rem 1rem;
    border: 1px solid var(--color-white);
    border-radius: 3.75rem;
    font-size: 0.875rem;
    color: var(--color-white);
    margin-bottom: 2.5rem;
}

/* 主标题 */
.banner-title {
    font-size: 4rem;
    font-weight: 700;
    color: var(--color-white);
    line-height: 1.15;
    margin: 0 0 1rem;
    text-shadow: 0 0.125rem 0.75rem rgba(0, 0, 0, 0.2);
}

/* 英文副标 */
.banner-subtitle {
    font-size: 1.25rem;
    color: var(--color-white);
    margin: 0 0 5rem;
}

/* 探索更多按钮 */
.banner-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.25rem 1.5rem 0.25rem 0.25rem;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 3.75rem;
    color: var(--color-white);
    text-decoration: none;
    font-size: 0.875rem;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    transition: background 0.3s, transform 0.3s;
}
.banner-btn:hover {
    background: rgba(255, 255, 255, 0.28);
    color: var(--color-white);
    transform: translateY(-0.125rem);
}

/* Swiper 分页器（圆角长条） */
.banner-pagination.swiper-pagination-bullets {
    bottom: 2.5rem;
}
.banner-pagination .swiper-pagination-bullet {
    width: 2.5rem;
    height: 0.25rem;
    border-radius: 0.125rem;
    background: rgba(255, 255, 255, 0.4);
    opacity: 1;
    margin: 0 0.375rem;
    transition: background 0.3s;
}
.banner-pagination .swiper-pagination-bullet-active {
    background: var(--color-white);
}

/* ==================== 第 2 区：关于我们 ==================== */
.about-section {
    background: var(--color-primary);
    color: var(--color-white);
}
.about-left {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    padding: 1rem 0;
    padding-right: 2rem;
    width: 50%;
}
.about-company {
    font-size: 2.25rem;
    font-weight: 500;
    color: var(--color-accent);
    margin: 0;
    line-height: 1.3;
}
.about-intro-wrap {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.about-line {
    width: 2px;
    background: var(--color-accent);
    flex-shrink: 0;
    height: 3rem;
}
.about-intro {
    display: flex;
    flex-direction: column;
    align-items: start;
    gap: 2rem;
    flex: 1;
}
.about-intro p {
    font-size: 1.125rem;
    line-height: 2em;
    color: var(--color-white);
    margin: 0;
}

/* 关于我们右侧图片卡片 */
.about-right { display: flex; flex-direction: column;padding-left: 2rem; width: 50%; }
.about-pic {
    height: 17.5rem;
    border-radius: 0.5rem;
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding: 1rem 0;
    position: relative;
    overflow: hidden;
    transition: transform 0.4s;
}
.about-pic::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 1) 100%);
}
.about-pic-text {
    position: relative;
    z-index: 2;
    color: var(--color-white);
    font-size: 1rem;
    font-weight: 700;
    text-align: center;
    padding: 0 1rem;
}
.about-pic:hover { transform: translateY(-0.25rem); }

/* ==================== 第 3 区：产品中心 ==================== */
.product-section {
    background: var(--color-bg);
}
.product-header {
    margin-bottom: 2rem;
    --bs-gutter-x: 3rem;
}
.product-desc {
    font-size: 1.25rem;
    line-height: 2em;
    color: var(--color-primary);
    margin: 0;
}

/* Tab 切换栏 */
.product-tabs { margin-bottom: 2.5rem; }
.tab-line {
    height: 1px;
    background: rgba(18, 38, 79, 0.5);
}
.product-tab-list {
    border: none;
    justify-content: space-between;
    align-items: center;
    flex-wrap: nowrap;
}
.product-tab-list .nav-item { position: relative; margin: 0.25rem 0; width: 33.33%; }
.product-tab-list .nav-item.active .v-line-item,
.product-tab-list .nav-item.active .v-line-radius {
    background: var(--color-primary);
}
.product-tab-list .nav-item .v-line{
    gap: 0.25rem;
}
.product-tab-list .nav-item .v-line-item{
    width: 1px;
    flex: 1 1 0;
    background: var(--color-text-4);
}
.product-tab-list .nav-item .v-line-radius{
    width: 0.5rem;
    height: 0.5rem;
    border-radius: 50%;
    background: var(--color-text-4);
}
.product-tab-list .nav-link {
    display: flex;
    align-items: center;
    border: none;
    background: none;
    padding: 3rem 0 3rem 2rem;
    color: var(--color-text-4);
    font-size: 2rem;
    font-weight: 700;
    text-align: left;
}
.product-tab-list .nav-link.active {
    color: var(--color-primary);
    background: none;
}

/* 产品 Swiper 容器 */
.product-swiper-wrap {
    position: relative;
}
.product-swiper {
    overflow: hidden;
    padding: 1rem 0 3rem;
}
.product-swiper-wrap a {
    display: block;
}
/* 产品卡片 */
.product-card {
    background: var(--color-white);
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: 0 0.25rem 1rem rgba(18, 38, 79, 0.06);
    transition: transform 0.3s, box-shadow 0.3s;
    height: auto;
}
.product-card:hover {
    transform: translateY(-0.375rem);
    box-shadow: 0 1rem 2.5rem rgba(18, 38, 79, 0.12);
}
.product-pic-wrap {
    padding: 2rem 3rem 0 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(180deg, var(--color-primary) 0%, var(--color-accent) 100%);
}
.product-pic-wrap .pic {
    width: 100%;
    border-radius: 0.5rem 0.5rem 0 0;
    transition: all 0.3s;
}
.product-card:hover .product-pic-wrap .pic {
    transform: scale(1.1);
}
.product-info {
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.product-cas-row {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.product-cas-label {
    font-size: 1rem;
    font-weight: 500;
    color: var(--color-primary);
    flex-shrink: 0;
}
.product-cas-line {
    height: 2px;
    flex: 1;
    background: var(--color-primary);
}
.product-cas-value {
    font-size: 1rem;
    color: var(--color-primary);
    font-weight: 500;
    flex-shrink: 0;
}
.product-name {
    font-size: clamp(1.125rem, 1.5vw, 1.5rem);
    color: var(--color-primary);
    margin: 0;
    font-weight: 400;
}
.product-more {
    padding-top: 2rem;
    text-align: right;
}
.product-more a {
    font-size: 0.875rem;
    color: var(--color-text);
    text-decoration: none;
    transition: color 0.2s;
}
.product-more a:hover { color: var(--color-accent); }

/* 左右切换箭头 */
.product-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 4rem;
    height: 4rem;
    cursor: pointer;
    z-index: 10;
    transition: transform 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}
.product-arrow img { width: 4rem; height: 4rem; }
.product-arrow:hover { transform: translateY(-50%) scale(1.1); }
.product-arrow-prev { left: -5rem;transform: translateY(-50%) rotate(180deg); }
.product-arrow-prev:hover {
    transform: translateY(-50%) rotate(180deg) scale(1.1);
}
.product-arrow-next {
    right: -5rem;
}


/* ==================== 第 4 区：技术服务 ==================== */
.service-section {
    background: var(--color-white);
}
.service-row {
    --bs-gutter-x: 2rem;
    margin-top: 2rem;
    counter-reset: svc;
}
.service-card {
    position: relative;
    display: block;
    height: 29.0625rem;
    border-radius: 1rem;
    overflow: hidden;
}
.service-row .col-lg-6:nth-child(2) .service-card {
    animation-delay: 0.2s;
}
.service-pic {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    transition: transform 0.6s;
    z-index: 1;
}
.service-pic.fixed-ratio::before {
    display: none;
}
.service-pic.fixed-ratio img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.service-card:hover .service-pic { transform: scale(1.06); }
.service-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 2;
    padding: 2rem;
    background: linear-gradient(180deg, rgba(18, 38, 79, 0) 0%, rgba(18, 38, 79, 0.9) 50%, rgba(18, 38, 79, 1) 100%);
    color: var(--color-white);
}
.service-num {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-white);
    display: block;
    margin-bottom: 0.5rem;
}
.service-num::before {
    counter-increment: svc;
    content: counter(svc, decimal-leading-zero);
}
.service-name {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--color-white);
    margin: 0 0 0.5rem;
}
.service-desc {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.5);
    margin: 0;
    line-height: 1.6;
}

/* ==================== 第 5 区：新闻中心 ==================== */
.news-section {
    background: var(--color-bg);
}
.news-row {
    --bs-gutter-x: 2rem;
    margin-top: 2rem;
}
/* 左侧特色新闻 */
.news-feature {
    background: var(--color-white);
    border-radius: 0.5rem;
    display: block;
    overflow: hidden;
    height: 100%;
    transition: transform 0.3s, box-shadow 0.3s;
}
.news-feature:hover {
    transform: translateY(-0.25rem);
    box-shadow: 0 1rem 2.5rem rgba(18, 38, 79, 0.1);
}
.news-info {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.news-tag {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border: 1px solid var(--color-primary);
    border-radius: 3.75rem;
    font-size: 0.75rem;
    color: var(--color-primary);
    width: fit-content;
}
.news-feature .news-title {
    font-size: 1.25rem;
    color: #040404;
    margin: 0;
    line-height: 1.5;
}
.news-summary {
    font-size: 0.875rem;
    color: var(--color-text-2);
    margin: 0;
    line-height: 1.6;
}
.news-time {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-text-3);
    font-size: 0.75rem;
}

/* 右侧新闻列表 */
.news-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    height: 100%;
}
.news-item {
    background: var(--color-white);
    border-radius: 0.5rem;
    padding: 1.5rem;
    transition: transform 0.3s, box-shadow 0.3s;
    flex: 1;
}
.news-item:hover {
    transform: translateY(-0.125rem);
    box-shadow: 0 0.75rem 1.5rem rgba(0, 0, 0, 0.06);
}
.news-item a {
    text-decoration: none;
    color: inherit;
    display: block;
}
.news-item-title {
    font-size: 1.25rem;
    color: #040404;
    margin: 0 0 1rem;
    line-height: 1.4;
    transition: color 0.2s;
}
.news-item:hover .news-item-title { color: var(--color-primary); }

@media (max-width: 1200px) {
    .banner-content{
        max-width: 80%;
    }
    .banner-slide{
        height: 80vh;
    }
    .banner-badge{
        font-size: 0.75rem;
    }
    .banner-title{
        font-size: 3.5rem;
    }
    .about-left{
        padding-right: 0;
        width: 100%;
        padding: 0;
        margin-bottom: 2rem;
    }
    .about-right{
        padding-left: 0;
        width: 100%;
    }
    .product-tab-list{
        align-items: normal;
    }
    .product-tab-list .nav-link{
        padding-left: 1rem;
        font-size: 1.75rem;
    }
    .product-arrow{
        display: none;
    }
    .news-item{
        padding: 1rem;
    }
    .news-item-title{
        margin-bottom: 0.25rem;
    }
}

/* ==================== 响应式适配 ==================== */
@media (max-width: 991px) {
    .banner-slide { height: 50vh; min-height: 30rem; }
    .banner-content { max-width: 100%; }
    .banner-btn{font-size: 0.75rem;}
    .about-left { padding: 0;gap: 1rem; }
    .about-pic{height: 24rem;}
    .about-company{font-size: 1.75rem;}
    .about-line{display: none;}
    .about-intro{align-items: center;}
    .about-intro p{font-size: 0.875rem;}
    .product-header{--bs-gutter-x:0}
    .product-desc{font-size: 0.875rem;}
    .product-swiper-wrap { padding: 0 1rem; }
    .product-header,.product-tabs{margin-bottom: 1rem;}
    .product-tab-list .nav-link { font-size: 1rem; padding:0.5rem;}
    .product-tab-list .nav-item { padding: 0; }
    .service-row{margin-top: 1rem;--bs-gutter-x:0;}
    .service-card { height: 22.5rem; }
    .news-row{gap: 1rem;--bs-gutter-x:0;}
    .news-pic { height: auto; }
}

@media (max-width: 575px) {
    .banner-title { font-size: 2rem; }
    .banner-subtitle { font-size: 0.875rem; margin-bottom: 2rem; }
    .banner-btn { padding: 0.25rem 1rem 0.25rem 0.25rem; }
    .about-pic{height: 13rem;}
    .product-tab-list .nav-item::before { height: 2.5rem; }
    .service-card { height: auto; margin-bottom: 1rem;}
    .service-overlay { padding: 1.25rem; }
    .service-name { font-size: 1.125rem; }
    .service-desc { font-size: 0.875rem; }
    
    .news-item { padding: 1rem; }
    .news-item-title { font-size: 1rem; }
    .news-feature .news-title { font-size: 1rem; }
    .product-arrow, .product-arrow img { width: 2.5rem; height: 2.5rem; }
}