/* =========================================
   1. 基础设置 (Base & Variables)
   ========================================= */
:root {
    --color-primary: #1a1a1a;
    --color-secondary: #f5f5f5;
    --color-white: #ffffff;
    --color-accent: #0a2540;
    --color-text-light: #666666;
    --font-main: 'Helvetica Neue', 'Helvetica', 'Arial', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    --spacing-container: 5%;
    --transition-speed: 0.5s;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--color-primary);
    line-height: 1.6;
    overflow-x: hidden;
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s ease;
}

img {
    display: block;
    width: 100%;
    height: auto;
}

/* =========================================
   2. 导航栏 (Navigation)
   ========================================= */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem var(--spacing-container);
    z-index: 1000;
    transition: background-color 0.4s ease, padding 0.4s ease;
    background-color: transparent; /* 初始透明 */
}

.main-nav.scrolled {
    background-color: rgba(255, 255, 255, 0.95);
    padding: 1rem var(--spacing-container);
    box-shadow: 0 2px 10px rgba(0,0,0,0.03);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--color-primary);
    z-index: 1001;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 3rem;
}

.nav-links li a {
    font-size: 0.9rem;
    letter-spacing: 1px;
    text-transform: uppercase;
    position: relative;
    font-weight: 300;
}

.nav-links li a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--color-primary);
    transition: width 0.3s ease;
}

.nav-links li a:hover::after,
.nav-links li a.active::after {
    width: 100%;
}

/* 汉堡菜单按钮 (移动端) */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    z-index: 1001;
    gap: 6px;
}

.hamburger span {
    width: 25px;
    height: 2px;
    background-color: var(--color-primary);
    transition: all 0.3s ease;
}

/* =========================================
   3. 首页: 全屏轮播 (Hero Slider)
   ========================================= */
.hero-slider {
    height: 100vh;
    width: 100%;
    position: relative;
    overflow: hidden;
    background-color: var(--color-primary);
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    visibility: hidden;
    transition: opacity 1.2s ease, visibility 1.2s ease;
    z-index: 1;
}

.slide.active {
    opacity: 1;
    visibility: visible;
    z-index: 2;
}

.slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 20%; /* 稍微偏上对齐 */
    transform: scale(1.05);
    transition: transform 6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.slide.active img {
    transform: scale(1);
}

.slide-content {
    position: absolute;
    bottom: 15%;
    left: var(--spacing-container);
    z-index: 3;
    color: var(--color-white);
    max-width: 600px;
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease 0.4s; /* 延迟显示文字 */
}

.slide.active .slide-content {
    opacity: 1;
    transform: translateY(0);
}

.slide-content h2 {
    font-size: 3rem;
    font-weight: 300;
    letter-spacing: 2px;
    margin-bottom: 1rem;
    text-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

/* =========================================
   4. 通用布局区域 (Sections)
   ========================================= */
section {
    padding: 6rem var(--spacing-container);
}

.section-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 300;
    letter-spacing: 3px;
    margin-bottom: 4rem;
    color: var(--color-primary);
}

/* 引言区域 */
.intro {
    background-color: var(--color-white);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    min-height: 40vh;
}

.intro h2 {
    font-size: 2.2rem;
    font-weight: 300;
    margin-bottom: 1.5rem;
    letter-spacing: 1px;
}

.intro p {
    font-size: 1.1rem;
    color: var(--color-text-light);
    letter-spacing: 1px;
    max-width: 600px;
}

/* =========================================
   5. 系列页面 (Collections Grid)
   ========================================= */
.collections-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2px; /* 极细间距 */
    padding: 0;
    margin-top: 80px; /* 避开固定导航栏 */
}

.collection-item {
    position: relative;
    overflow: hidden;
    aspect-ratio: 4/5;
    cursor: pointer;
    background-color: #f0f0f0;
}

.collection-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s cubic-bezier(0.215, 0.610, 0.355, 1.000);
}

.collection-item:hover img {
    transform: scale(1.03);
}

.collection-info {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 2rem;
    background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
    color: var(--color-white);
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.4s ease;
}

.collection-item:hover .collection-info {
    opacity: 1;
    transform: translateY(0);
}

.collection-info h3 {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: 0.5rem;
    letter-spacing: 1px;
}

.collection-info p {
    font-size: 0.9rem;
    font-weight: 300;
    opacity: 0.9;
}

/* =========================================
   6. 细节页面 (Details)
   ========================================= */
.details-container {
    padding-top: 120px; /* 导航栏高度补正 */
    max-width: 1600px;
    margin: 0 auto;
}

.detail-row {
    display: flex;
    align-items: center;
    margin-bottom: 8rem;
    gap: 5%;
}

.detail-row:nth-child(even) {
    flex-direction: row-reverse;
}

.detail-image {
    flex: 1.2;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.detail-image img {
    transition: transform 0.8s ease;
}

.detail-image:hover img {
    transform: scale(1.05);
}

.detail-text {
    flex: 1;
    padding: 2rem;
}

.detail-text h3 {
    font-size: 1.8rem;
    font-weight: 300;
    margin-bottom: 1.5rem;
    color: var(--color-accent);
}

.detail-text p {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--color-text-light);
    margin-bottom: 1rem;
}

.detail-meta {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: #999;
    margin-bottom: 0.5rem;
    display: block;
}

/* =========================================
   7. 页脚 (Footer)
   ========================================= */
footer {
    padding: 3rem var(--spacing-container);
    text-align: center;
    background-color: var(--color-secondary);
    color: var(--color-text-light);
    font-size: 0.8rem;
    letter-spacing: 1px;
}

/* =========================================
   8. 动态槽位 (Dynamic Slots)
   ========================================= */
.app-slot {
    display: none; /* 默认隐藏，用于后续扩展 */
}

/* =========================================
   9. 响应式设计 (Responsive)
   ========================================= */
@media (max-width: 1024px) {
    .collections-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .slide-content h2 {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    /* 导航栏汉堡菜单 */
    .hamburger {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background-color: var(--color-white);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: right 0.4s ease;
        box-shadow: -5px 0 15px rgba(0,0,0,0.1);
        gap: 2rem;
    }

    .nav-links.active {
        right: 0;
    }

    .nav-links li a {
        color: var(--color-primary);
        font-size: 1.2rem;
    }
    
    /* 汉堡按钮动画 */
    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 6px);
    }
    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }
    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -6px);
    }

    /* 布局调整 */
    .collections-grid {
        grid-template-columns: 1fr;
    }

    .detail-row, .detail-row:nth-child(even) {
        flex-direction: column;
        gap: 2rem;
        margin-bottom: 4rem;
    }
    
    .detail-text {
        text-align: center;
        padding: 1rem 0;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .slide-content {
        bottom: 10%;
        width: 90%;
    }
    
    .slide-content h2 {
        font-size: 2rem;
    }
}