/* ============================================
   樱花视频 - 完整样式表 (style.css)
   风格: 渐变Banner, 圆角卡片, 毛玻璃效果, 响应式, 暗色模式, 滚动动画, hover动画
   ============================================ */

/* --- 基础重置与变量 --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #d4a5a5;
    --primary-dark: #b88484;
    --primary-light: #f2dada;
    --bg: #fef9f9;
    --bg-card: rgba(255, 255, 255, 0.7);
    --bg-glass: rgba(255, 255, 255, 0.25);
    --text: #2c2c2c;
    --text-secondary: #555;
    --text-inverse: #fff;
    --border: rgba(212, 165, 165, 0.3);
    --shadow: 0 8px 32px rgba(212, 165, 165, 0.15);
    --shadow-hover: 0 12px 40px rgba(212, 165, 165, 0.25);
    --gradient-banner: linear-gradient(135deg, #fce4e4 0%, #d4a5a5 50%, #b88484 100%);
    --gradient-card: linear-gradient(135deg, rgba(255,255,255,0.6), rgba(255,255,255,0.1));
    --radius: 16px;
    --radius-sm: 8px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --max-width: 1200px;
    --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
    --scroll-offset: 30px;
}

/* 暗色模式 */
[data-theme="dark"] {
    --bg: #1a1a1a;
    --bg-card: rgba(40, 40, 40, 0.7);
    --bg-glass: rgba(30, 30, 30, 0.4);
    --text: #eaeaea;
    --text-secondary: #aaa;
    --border: rgba(180, 132, 132, 0.4);
    --shadow: 0 8px 32px rgba(0,0,0,0.3);
    --shadow-hover: 0 12px 40px rgba(0,0,0,0.4);
    --gradient-banner: linear-gradient(135deg, #2a1f1f 0%, #5a3a3a 50%, #3a2525 100%);
    --gradient-card: linear-gradient(135deg, rgba(40,40,40,0.6), rgba(30,30,30,0.1));
}

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

body {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    transition: background var(--transition), color var(--transition);
    overflow-x: hidden;
    min-height: 100vh;
}

/* --- 滚动动画基础 --- */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(var(--scroll-offset));
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- 通用元素 --- */
a {
    color: var(--primary-dark);
    text-decoration: none;
    transition: color var(--transition);
}

a:hover, a:focus {
    color: var(--primary);
    text-decoration: underline;
}

img, svg {
    max-width: 100%;
    display: block;
}

h1, h2, h3, h4, h5, h6 {
    line-height: 1.3;
    margin-bottom: 0.5em;
    font-weight: 600;
}

h1 { font-size: clamp(1.8rem, 5vw, 2.8rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.2rem); margin-top: 2em; }
h3 { font-size: clamp(1.2rem, 3vw, 1.6rem); margin-top: 1.5em; }

p {
    margin-bottom: 1em;
    color: var(--text-secondary);
}

section {
    padding: 4rem 1.5rem;
    max-width: var(--max-width);
    margin: 0 auto;
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
    border: 1px solid var(--border);
    transition: background var(--transition), box-shadow var(--transition), border var(--transition);
}

/* --- 头部与导航 --- */
header {
    position: relative;
    z-index: 10;
}

nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    padding: 0.8rem 1.5rem;
    background: var(--bg-glass);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background var(--transition), border var(--transition);
}

.logo {
    flex-shrink: 0;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1.2rem;
    flex-wrap: wrap;
    padding: 0.5rem 0;
}

.nav-links a {
    font-weight: 500;
    padding: 0.3rem 0.6rem;
    border-radius: var(--radius-sm);
    transition: background var(--transition), color var(--transition);
}

.nav-links a:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
    text-decoration: none;
}

.search-box {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.search-box input {
    padding: 0.4rem 0.8rem;
    border: 1px solid var(--border);
    border-radius: 20px;
    background: var(--bg-card);
    color: var(--text);
    font-size: 0.9rem;
    outline: none;
    transition: border var(--transition), box-shadow var(--transition);
    width: 140px;
}

.search-box input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(212,165,165,0.2);
}

.search-box button {
    padding: 0.4rem 1rem;
    border: none;
    border-radius: 20px;
    background: var(--gradient-banner);
    color: var(--text-inverse);
    font-weight: 600;
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition);
}

.search-box button:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 15px rgba(212,165,165,0.4);
}

.dark-mode-toggle, .mobile-menu-btn {
    background: none;
    border: none;
    font-size: 1.4rem;
    cursor: pointer;
    padding: 0.3rem 0.6rem;
    border-radius: 50%;
    transition: background var(--transition), transform var(--transition);
    color: var(--text);
}

.dark-mode-toggle:hover, .mobile-menu-btn:hover {
    background: var(--primary-light);
    transform: rotate(10deg);
}

.mobile-menu-btn {
    display: none;
}

/* --- Hero 区域 (渐变Banner) --- */
.hero {
    position: relative;
    background: var(--gradient-banner);
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 4rem 1.5rem;
    border-radius: 0 0 var(--radius) var(--radius);
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 40%, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: heroGlow 8s ease-in-out infinite alternate;
}

@keyframes heroGlow {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(10%, 10%) scale(1.2); }
}

.hero-slider {
    position: relative;
    z-index: 2;
    width: 100%;
    max-width: 800px;
}

.slide {
    display: none;
    animation: fadeSlide 0.8s ease-out;
}

.slide.active {
    display: block;
}

@keyframes fadeSlide {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.slide h1, .slide h2 {
    color: var(--text-inverse);
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.slide p {
    color: rgba(255,255,255,0.9);
    font-size: 1.1rem;
    margin: 1rem 0 2rem;
}

.cta-btn {
    display: inline-block;
    background: var(--text-inverse);
    color: var(--primary-dark);
    padding: 0.8rem 2.5rem;
    border-radius: 30px;
    font-weight: 700;
    font-size: 1.05rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
    text-decoration: none;
}

.cta-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
    background: var(--primary-light);
    color: var(--primary-dark);
    text-decoration: none;
}

.slider-controls {
    display: flex;
    justify-content: center;
    gap: 0.6rem;
    margin-top: 2rem;
    position: relative;
    z-index: 2;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.4);
    cursor: pointer;
    transition: background var(--transition), transform var(--transition);
}

.dot.active, .dot:hover {
    background: var(--text-inverse);
    transform: scale(1.3);
}

/* --- 圆角卡片风格 (应用于section内部) --- */
.card, .faq-item, article, .case-item {
    background: var(--gradient-card);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.2rem;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
}

.card:hover, .faq-item:hover, article:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

/* --- FAQ 手风琴效果 (纯CSS) --- */
.faq-item {
    cursor: pointer;
}

.faq-item h3 {
    position: relative;
    padding-right: 2rem;
    margin: 0;
    font-size: 1.1rem;
}

.faq-item h3::after {
    content: '+';
    position: absolute;
    right: 0;
    top: 0;
    font-size: 1.4rem;
    font-weight: 300;
    transition: transform var(--transition);
}

.faq-item.active h3::after {
    transform: rotate(45deg);
}

.faq-item p {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out, margin 0.3s;
    margin: 0;
}

.faq-item.active p {
    max-height: 300px;
    margin-top: 0.8rem;
}

/* --- 文章列表 --- */
article {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

article h3 {
    margin: 0;
}

article time {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

article a {
    align-self: flex-start;
    font-weight: 600;
}

/* --- 联系与站点地图 --- */
#contact p, #sitemap ul {
    margin-bottom: 0.6rem;
}

#sitemap ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
}

#sitemap ul li a {
    padding: 0.3rem 0.8rem;
    border-radius: var(--radius-sm);
    background: var(--bg-glass);
    border: 1px solid var(--border);
    transition: background var(--transition), border var(--transition);
}

#sitemap ul li a:hover {
    background: var(--primary-light);
    border-color: var(--primary);
    text-decoration: none;
}

/* --- Footer --- */
footer {
    text-align: center;
    padding: 2rem 1.5rem;
    background: var(--bg-glass);
    backdrop-filter: blur(8px);
    border-top: 1px solid var(--border);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

footer p {
    margin: 0.3rem 0;
}

footer a {
    color: var(--primary-dark);
}

/* --- 返回顶部 --- */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--gradient-banner);
    color: var(--text-inverse);
    border: none;
    font-size: 1.4rem;
    cursor: pointer;
    box-shadow: var(--shadow);
    transition: transform var(--transition), opacity var(--transition), box-shadow var(--transition);
    opacity: 0;
    visibility: hidden;
    z-index: 99;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-5px) scale(1.05);
    box-shadow: var(--shadow-hover);
}

/* --- 响应式设计 --- */
@media (max-width: 1024px) {
    nav {
        flex-wrap: wrap;
        gap: 0.5rem;
    }
    .nav-links {
        order: 3;
        width: 100%;
        justify-content: center;
    }
    .search-box {
        order: 2;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        align-items: center;
        width: 100%;
        background: var(--bg-glass);
        backdrop-filter: blur(16px);
        border-radius: var(--radius);
        padding: 1rem;
        gap: 0.8rem;
    }
    .nav-links.open {
        display: flex;
    }
    .mobile-menu-btn {
        display: block;
    }
    .search-box input {
        width: 100px;
    }
    .hero {
        min-height: 50vh;
        padding: 3rem 1rem;
    }
    section {
        padding: 2rem 1rem;
        margin-bottom: 1.5rem;
    }
    .card, .faq-item, article {
        padding: 1rem;
    }
    .back-to-top {
        bottom: 1rem;
        right: 1rem;
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    .logo svg {
        width: 100px;
        height: auto;
    }
    .search-box input {
        width: 80px;
    }
    .cta-btn {
        padding: 0.6rem 1.8rem;
        font-size: 0.95rem;
    }
}

/* --- 暗色模式额外微调 --- */
[data-theme="dark"] .cta-btn {
    background: var(--primary-dark);
    color: var(--text-inverse);
}

[data-theme="dark"] .cta-btn:hover {
    background: var(--primary);
}

[data-theme="dark"] .search-box button {
    background: var(--primary-dark);
}

/* --- 打印样式 --- */
@media print {
    nav, .hero, .back-to-top, .slider-controls, .dark-mode-toggle, .mobile-menu-btn {
        display: none !important;
    }
    body {
        background: white;
        color: black;
    }
    section {
        box-shadow: none;
        border: 1px solid #ddd;
        backdrop-filter: none;
        background: white;
    }
}