/* ============================================
   homepage.css - 首页专用样式和动画定义
   ============================================ */

/* --- 平滑滚动 --- */
html {
    scroll-behavior: smooth;
}

/* --- 强制页面容器垂直布局 --- */
.page {
    display: flex;
    flex-direction: column !important;
    overflow-y: auto;
}

/* ============================================
   Task 1.1: 滚动动画基类和动画关键帧
   ============================================ */

/* 滚动动画基类 - 初始隐藏 */
.scroll-animate {
    opacity: 0;
    will-change: transform, opacity;
}

/* 3秒超时 fallback：JS 加载失败时自动显示 */
@keyframes fallback-show {
    to {
        opacity: 1;
    }
}

.scroll-animate:not(.animated) {
    animation: fallback-show 0.6s ease-out 3s forwards;
}

/* --- 淡入动画 --- */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.fade-in.animated {
    animation: fadeIn 0.6s ease-out forwards;
}

/* --- 从下方滑入 --- */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.slide-up.animated {
    animation: slideUp 0.6s ease-out forwards;
}

/* --- 从左侧滑入 --- */
@keyframes slideLeft {
    from {
        opacity: 0;
        transform: translateX(-40px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.slide-left.animated {
    animation: slideLeft 0.6s ease-out forwards;
}

/* --- 从右侧滑入 --- */
@keyframes slideRight {
    from {
        opacity: 0;
        transform: translateX(40px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.slide-right.animated {
    animation: slideRight 0.6s ease-out forwards;
}

/* --- 缩放出现 --- */
@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.8);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.scale-in.animated {
    animation: scaleIn 0.6s ease-out forwards;
}

/* --- 交错延迟类 (stagger-delay-1 ~ stagger-delay-12) --- */
.stagger-delay-1 { animation-delay: 0.1s; }
.stagger-delay-2 { animation-delay: 0.2s; }
.stagger-delay-3 { animation-delay: 0.3s; }
.stagger-delay-4 { animation-delay: 0.4s; }
.stagger-delay-5 { animation-delay: 0.5s; }
.stagger-delay-6 { animation-delay: 0.6s; }
.stagger-delay-7 { animation-delay: 0.7s; }
.stagger-delay-8 { animation-delay: 0.8s; }
.stagger-delay-9 { animation-delay: 0.9s; }
.stagger-delay-10 { animation-delay: 1.0s; }
.stagger-delay-11 { animation-delay: 1.1s; }
.stagger-delay-12 { animation-delay: 1.2s; }

/* ============================================
   Task 1.2: 固定导航栏样式
   ============================================ */

.sticky-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transform: translateY(-100%);
    transition: transform 0.4s ease-out;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 8px rgba(0, 0, 0, 0.08);
    padding: 0 24px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.sticky-nav.visible {
    transform: translateY(0);
}

.sticky-nav .nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.sticky-nav .nav-brand span {
    font-size: 1rem;
    font-weight: 600;
    color: #1d1d1f;
}

.sticky-nav .nav-download-btn {
    background: #0071e3;
    color: #fff;
    border: none;
    border-radius: 20px;
    padding: 6px 20px;
    font-size: 0.85rem;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.2s ease;
}

.sticky-nav .nav-download-btn:hover {
    background: #0077ed;
}

/* ============================================
   Task 1.3: 各 Section 样式
   ============================================ */

/* --- Hero Section --- */
.hero-section {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
    text-align: center;
    padding: 80px 24px 60px;
    position: relative;
}

.hero-section .hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: #1d1d1f;
    margin: 0;
    line-height: 1.1;
}

.hero-section .hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    color: #6e6e73;
    margin: 8px 0 0;
}

.hero-section .hero-tagline {
    font-size: 1.25rem;
    color: #86868b;
    margin: 24px 0 0;
}

.hero-section .hero-cta {
    display: inline-block;
    margin-top: 40px;
    padding: 14px 36px;
    background: #0071e3;
    color: #fff;
    border-radius: 28px;
    font-size: 1.1rem;
    text-decoration: none;
    transition: background 0.2s ease;
    border: none;
    cursor: pointer;
}

.hero-section .hero-cta:hover {
    background: #0077ed;
}

/* --- Feature Section --- */
.feature-section {
    padding: 100px 24px;
    background: #ffffff;
    text-align: center;
}

.feature-section .section-title {
    font-size: 2.2rem;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 60px;
}

/* --- Showcase Section (产品截图展示区) --- */
.showcase-section {
    padding: 100px 24px;
    background: #f5f5f7;
}

.showcase-section .section-title {
    font-size: 2rem;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
}

.showcase-section .section-desc {
    font-size: 1.1rem;
    color: #6e6e73;
    margin-bottom: 8px;
}

/* --- Download Section --- */
.download-section {
    padding: 100px 24px;
    background: #ffffff;
    text-align: center;
}

.download-section .section-title {
    font-size: 2.2rem;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 48px;
}

.download-section .download-buttons {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px;
    margin-bottom: 32px;
}

.download-section .download-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: 12px;
    background: #f5f5f7;
    color: #1d1d1f;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    transition: background 0.2s ease, transform 0.2s ease;
    border: 1px solid #d2d2d7;
}

.download-section .download-btn:hover {
    background: #e8e8ed;
    transform: translateY(-2px);
}

.download-section .privacy-text {
    font-size: 0.85rem;
    color: #86868b;
}

.download-section .privacy-text a {
    color: #0071e3;
    text-decoration: none;
}

.download-section .privacy-text a:hover {
    text-decoration: underline;
}

/* --- Gallery Section (模板画廊) --- */
.gallery-section {
    padding: 100px 24px;
    background: #f5f5f7;
    text-align: center;
}

.gallery-section .section-title {
    font-size: 2.2rem;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 60px;
}

.gallery-section .gallery-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 16px;
    max-width: 1200px;
    margin: 0 auto;
}

.gallery-section .gallery-item {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.gallery-section .gallery-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.gallery-section .gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* --- Footer Section --- */
.footer-section {
    padding: 40px 24px;
    background: #1d1d1f;
    text-align: center;
}

.footer-section a {
    color: #86868b;
    text-decoration: none;
    font-size: 0.9rem;
}

.footer-section a:hover {
    color: #d2d2d7;
}

/* ============================================
   Task 1.4: 响应式媒体查询
   ============================================ */

@media (max-width: 768px) {
    /* Hero 文字缩小 */
    .hero-section .hero-title {
        font-size: 2.2rem;
    }

    .hero-section .hero-subtitle {
        font-size: 1.1rem;
    }

    .hero-section .hero-tagline {
        font-size: 1rem;
    }

    .hero-section .hero-cta {
        padding: 12px 28px;
        font-size: 1rem;
    }

    /* Section 内边距缩小 */
    .feature-section,
    .showcase-section,
    .download-section,
    .gallery-section {
        padding: 60px 16px;
    }

    /* 功能卡片单列 */
    .feature-section .mud-grid-item {
        flex-basis: 100% !important;
        max-width: 100% !important;
    }

    /* 产品截图展示区单列 */
    .showcase-section .mud-grid-item {
        flex-basis: 100% !important;
        max-width: 100% !important;
    }

    /* 下载按钮单列 */
    .download-section .download-buttons {
        flex-direction: column;
        align-items: center;
    }

    .download-section .download-btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }

    /* 模板画廊从 6 列调整为 2 列 */
    .gallery-section .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    /* 导航栏移动端适配 */
    .sticky-nav {
        padding: 0 12px;
        height: 48px;
    }

    .sticky-nav .nav-brand span {
        font-size: 0.85rem;
    }

    .sticky-nav .nav-download-btn {
        padding: 5px 14px;
        font-size: 0.8rem;
    }

    /* Section 标题缩小 */
    .feature-section .section-title,
    .download-section .section-title,
    .gallery-section .section-title {
        font-size: 1.6rem;
        margin-bottom: 36px;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    /* 模板画廊中等屏幕 3 列 */
    .gallery-section .gallery-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}