/* ========== 基础变量 ========== */
:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --dark: #1e293b;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --shadow-sm: 0 1px 2px 0 rgba(0,0,0,0.05);
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
    --radius: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    -webkit-tap-highlight-color: transparent;
}

/* ========== 导航栏 ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    height: 64px;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255,255,255,0.95);
    border-bottom-color: var(--gray-200);
    box-shadow: var(--shadow-sm);
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.nav-logo {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    object-fit: cover;
}

.nav-logo-placeholder {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    background: var(--primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
}

.nav-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--gray-900);
}

.nav-links {
    display: flex;
    gap: 8px;
}

.nav-link {
    padding: 8px 16px;
    border-radius: 8px;
    text-decoration: none;
    color: var(--gray-500);
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--primary);
    background: var(--gray-100);
}

.nav-link.active {
    color: var(--primary);
    background: rgba(59,130,246,0.1);
}

/* ========== 主横幅 ========== */
.hero-section {
    padding: 120px 24px 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: rgba(255,255,255,0.05);
    border-radius: 50%;
}

.hero-section::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 400px;
    height: 400px;
    background: rgba(255,255,255,0.03);
    border-radius: 50%;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
    position: relative;
    z-index: 1;
}

.app-info {
    flex: 1;
    color: #fff;
}

.app-logo-wrapper {
    width: 100px;
    height: 100px;
    border-radius: 24px;
    overflow: hidden;
    background: #fff;
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.app-logo-wrapper.placeholder {
    background: rgba(255,255,255,0.2);
    color: #fff;
}

.app-logo {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.app-name {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.app-desc {
    font-size: 16px;
    opacity: 0.85;
    margin-bottom: 20px;
    max-width: 400px;
}

.version-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: rgba(255,255,255,0.2);
    border-radius: 100px;
    font-size: 14px;
    font-weight: 600;
    backdrop-filter: blur(10px);
}

/* ========== 下载分区区域 ========== */
.download-area {
    flex-shrink: 0;
    width: 420px;
    background: rgba(255,255,255,0.95);
    border-radius: var(--radius-lg);
    padding: 28px;
    box-shadow: var(--shadow-xl);
    backdrop-filter: blur(20px);
}

.download-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--gray-100);
    padding: 4px;
    border-radius: 10px;
}

.download-tab {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 8px;
    border: none;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    background: transparent;
    color: var(--gray-500);
    transition: var(--transition);
}

.download-tab:hover {
    color: var(--gray-700);
}

.download-tab.active {
    background: #fff;
    color: var(--gray-900);
    box-shadow: var(--shadow-sm);
}

.download-tab .tab-icon {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

.download-panel {
    display: none;
}

.download-panel.active {
    display: block;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: var(--transition);
}

/* ========== 下载按钮优化 ========== */
.btn-download {
    width: 100%;
    padding: 18px 24px;
    color: #fff;
    font-size: 16px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 16px;
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: flex-start;
    gap: 16px;
    border-radius: 14px;
    position: relative;
    overflow: hidden;
}

/* 按钮背景装饰 */
.btn-download::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 120px;
    height: 120px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
    pointer-events: none;
}

.btn-download svg,
.btn-download .tab-icon {
    width: 36px;
    height: 36px;
    flex-shrink: 0;
    flex-grow: 0;
    stroke-width: 1.8;
}

.btn-text {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    line-height: 1.3;
    flex: 1;
    min-width: 0;
    overflow: hidden;
}

.btn-label {
    font-size: 17px;
    font-weight: 700;
    white-space: nowrap;
}

.btn-platform {
    font-size: 13px;
    opacity: 0.85;
    font-weight: 500;
    white-space: nowrap;
}

.btn-android { background: linear-gradient(135deg, #3ddc84, #2db96f); }
.btn-android:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(61,220,132,0.35); }

.btn-ios { background: linear-gradient(135deg, #007aff, #0051d5); }
.btn-ios:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(0,122,255,0.35); }

.btn-windows { background: linear-gradient(135deg, #00a4ef, #0078d4); }
.btn-windows:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(0,164,239,0.35); }

.update-desc {
    padding-top: 16px;
    border-top: 1px solid var(--gray-200);
}

.update-desc h4 {
    font-size: 13px;
    color: var(--gray-500);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.update-desc p {
    font-size: 14px;
    color: var(--gray-600);
    line-height: 1.7;
}

.no-update {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray-400);
}

.no-update p {
    margin-top: 12px;
    font-size: 14px;
}

/* ========== 历史版本 ========== */
.history-section {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 24px;
}

.section-title {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 24px;
}

.section-title svg {
    color: var(--primary);
}

.history-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--gray-100);
    padding: 4px;
    border-radius: 10px;
    width: fit-content;
}

.history-tab {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 16px;
    border: none;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    background: transparent;
    color: var(--gray-500);
    transition: var(--transition);
}

.history-tab:hover {
    color: var(--gray-700);
}

.history-tab.active {
    background: #fff;
    color: var(--gray-900);
    box-shadow: var(--shadow-sm);
}

.history-panel {
    display: none;
}

.history-panel.active {
    display: block;
}

.history-list {
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-100);
    transition: var(--transition);
}

.history-item:last-child {
    border-bottom: none;
}

.history-item:hover {
    background: var(--gray-50);
}

.history-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.history-version {
    font-size: 15px;
    font-weight: 700;
    color: var(--gray-900);
}

.history-platform {
    padding: 3px 10px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
}

.badge-android { background: rgba(61,220,132,0.1); color: #2db96f; }
.badge-ios { background: rgba(0,122,255,0.1); color: #007aff; }
.badge-windows { background: rgba(0,164,239,0.1); color: #00a4ef; }

.history-date {
    font-size: 13px;
    color: var(--gray-400);
}

.btn-sm {
    padding: 6px 14px;
    font-size: 13px;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--gray-200);
    color: var(--gray-600);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(59,130,246,0.05);
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

/* ========== 截图区域 ========== */
.screenshots-section {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 24px;
}

.screenshots-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.screenshot-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: var(--transition);
}

.screenshot-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.screenshot-img-wrapper {
    position: relative;
    aspect-ratio: 16/10;
    overflow: hidden;
    background: var(--gray-100);
}

.screenshot-img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.screenshot-card:hover .screenshot-img-wrapper img {
    transform: scale(1.05);
}

.screenshot-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
    color: #fff;
}

.screenshot-card:hover .screenshot-overlay {
    opacity: 1;
}

.screenshot-info {
    padding: 12px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.screenshot-name {
    font-size: 13px;
    color: var(--gray-700);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 200px;
}

.screenshot-size {
    font-size: 12px;
    color: var(--gray-400);
    flex-shrink: 0;
}

.empty-state {
    text-align: center;
    padding: 80px 20px;
    color: var(--gray-400);
}

.empty-state p {
    margin-top: 16px;
    font-size: 15px;
}

/* ========== 客服区域 ========== */
.contact-section {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 24px 60px;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 20px;
    margin-bottom: 24px;
}

.contact-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    text-align: center;
}

.contact-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.contact-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    color: #fff;
}

.bg-blue { background: linear-gradient(135deg, #3b82f6, #2563eb); }
.bg-green { background: linear-gradient(135deg, #10b981, #059669); }
.bg-purple { background: linear-gradient(135deg, #8b5cf6, #7c3aed); }
.bg-orange { background: linear-gradient(135deg, #f59e0b, #d97706); }

.contact-info h3 {
    font-size: 16px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.contact-avatar {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    overflow: hidden;
    margin: 0 auto 12px;
    border: 3px solid var(--gray-100);
}

.contact-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.contact-detail {
    font-size: 14px;
    color: var(--gray-600);
    margin-bottom: 12px;
    word-break: break-all;
}

.contact-detail.phone {
    font-size: 18px;
    font-weight: 700;
    color: var(--gray-900);
}

.contact-hint {
    font-size: 12px;
    color: var(--gray-400);
    margin-top: 8px;
}

.qrcode-box {
    width: 140px;
    height: 140px;
    margin: 0 auto 8px;
    border-radius: 12px;
    overflow: hidden;
    border: 2px solid var(--gray-100);
    cursor: pointer;
    transition: var(--transition);
}

.qrcode-box:hover {
    border-color: var(--primary);
    transform: scale(1.05);
}

.qrcode-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.work-time {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 16px;
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    color: var(--gray-500);
    font-size: 14px;
}

.work-time svg {
    color: var(--warning);
}

/* ========== 页脚 ========== */
.footer {
    text-align: center;
    padding: 24px;
    color: var(--gray-400);
    font-size: 13px;
    border-top: 1px solid var(--gray-200);
}

/* ========== 预览弹窗 ========== */
.preview-modal {
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0,0,0,0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    padding: 20px;
}

.preview-modal.show {
    opacity: 1;
    visibility: visible;
}

.preview-content {
    position: relative;
    max-width: 90vw;
    max-height: 90vh;
}

.preview-content img {
    max-width: 100%;
    max-height: 85vh;
    border-radius: var(--radius);
    box-shadow: 0 25px 50px -12px rgba(0,0,0,0.5);
}

.preview-close {
    position: absolute;
    top: -48px;
    right: 0;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
    border: none;
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.preview-close:hover {
    background: rgba(255,255,255,0.2);
}

/* ========== 响应式 ========== */
@media (max-width: 768px) {
    .navbar {
        padding: 0 16px;
    }

    .nav-links {
        display: none;
    }

    .hero-section {
        padding: 100px 16px 40px;
    }

    .hero-content {
        flex-direction: column;
        gap: 32px;
    }

    .app-name {
        font-size: 28px;
    }

    .download-area {
        width: 100%;
        padding: 20px;
    }

    .download-tabs {
        padding: 3px;
    }

    .download-tab {
        padding: 8px 4px;
        font-size: 12px;
    }

    .download-tab .tab-icon {
        width: 16px;
        height: 16px;
    }

    .btn-download {
        padding: 14px 16px;
        gap: 12px;
    }

    .btn-download svg,
    .btn-download .tab-icon {
        width: 28px;
        height: 28px;
    }

    .btn-label {
        font-size: 15px;
    }

    .btn-platform {
        font-size: 12px;
    }

    .history-tabs {
        width: 100%;
    }

    .screenshots-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 12px;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .history-info {
        flex-wrap: wrap;
    }
}

@media (max-width: 480px) {
    .screenshots-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .app-logo-wrapper {
        width: 80px;
        height: 80px;
    }
}