/* ===== 全局重置 & 基础 ===== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --primary-gradient: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
    --text-dark: #0f172a;
    --text-muted: #64748b;
    --bg-gray: #f8fafc;
    --border-color: #e2e8f0;
    --shadow: 0 4px 20px rgba(37, 99, 235, 0.15);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}
html {
    scroll-behavior: smooth;
}
body {
    font-family: var(--font-family);
    background: var(--bg-gray);
    color: var(--text-dark);
    line-height: 1.6;
    padding-bottom: 80px;
    /* 为底部悬浮按钮留空间 */
}
a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}
a:hover {
    color: var(--primary-dark);
}
img {
    display: block;
    max-width: 100%;
    height: auto;
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

/* ===== 顶部导航 ===== */
.navbar {
    background: #ffffff;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(12px);
    background: rgba(255, 255, 255, 0.92);
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.04);
}
.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
}
.navbar-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 20px;
    color: var(--text-dark);
    flex-shrink: 0;
}
.navbar-brand img {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    background: var(--primary);
    object-fit: cover;
}
.navbar-brand span {
    color: var(--primary);
}
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.nav-toggle span {
    display: block;
    width: 24px;
    height: 2.5px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: var(--transition);
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 6px;
    list-style: none;
    flex-wrap: wrap;
}
.nav-links li a {
    display: block;
    padding: 6px 14px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-muted);
    border-radius: 8px;
    transition: var(--transition);
    white-space: nowrap;
}
.nav-links li a:hover,
.nav-links li a.active {
    color: var(--primary);
    background: var(--primary-light);
}
.nav-links li a.download-nav {
    background: var(--primary);
    color: #fff;
    padding: 6px 18px;
    border-radius: 20px;
}
.nav-links li a.download-nav:hover {
    background: var(--primary-dark);
    color: #fff;
}

/* ===== Hero 区域 ===== */
.hero {
    background: var(--primary-gradient);
    padding: 40px 0 50px;
    color: #fff;
    position: relative;
    overflow: hidden;
}
.hero::after {
    content: '';
    position: absolute;
    right: -20%;
    top: -30%;
    width: 60%;
    height: 120%;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    transform: rotate(-10deg);
    pointer-events: none;
}
.hero .container {
    position: relative;
    z-index: 1;
    display: flex;
    align-items: center;
    gap: 30px;
    flex-wrap: wrap;
}
.hero-left {
    flex: 1 1 300px;
}
.hero-app-icon {
    display: flex;
    align-items: center;
    gap: 18px;
    margin-bottom: 12px;
}
.hero-app-icon img {
    width: 80px;
    height: 80px;
    border-radius: 20px;
    background: #fff;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    object-fit: cover;
}
.hero-app-icon .app-name {
    font-size: 28px;
    font-weight: 800;
    letter-spacing: 0.5px;
}
.hero-app-icon .app-name small {
    font-size: 16px;
    font-weight: 400;
    opacity: 0.8;
    display: block;
}
.hero-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 10px 0 16px;
}
.hero-tags span {
    background: rgba(255, 255, 255, 0.18);
    backdrop-filter: blur(4px);
    padding: 4px 14px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid rgba(255, 255, 255, 0.2);
}
.hero-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin: 16px 0 12px;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    font-family: inherit;
}
.btn-primary {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.1);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
    color: var(--primary-dark);
}
.btn-outline-light {
    background: transparent;
    color: #fff;
    border: 2px solid rgba(255, 255, 255, 0.5);
}
.btn-outline-light:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: #fff;
}
.btn-sm {
    padding: 8px 20px;
    font-size: 14px;
}
.btn-android {
    background: #3ddc84;
    color: #1a1a1a;
}
.btn-android:hover {
    background: #34c77a;
    color: #1a1a1a;
    transform: translateY(-2px);
}
.btn-ios {
    background: #1a1a1a;
    color: #fff;
}
.btn-ios:hover {
    background: #2d2d2d;
    transform: translateY(-2px);
}
.hero-quick-links {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 14px;
}
.hero-quick-links a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 13px;
    padding: 4px 12px;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.15);
    transition: var(--transition);
}
.hero-quick-links a:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.2);
}
.hero-right {
    flex: 0 0 240px;
    display: flex;
    justify-content: center;
    align-items: center;
}
.hero-right img {
    width: 100%;
    max-width: 220px;
    border-radius: var(--radius);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.25);
    transform: rotate(2deg);
    transition: var(--transition);
    background: #fff;
    padding: 6px;
}
.hero-right img:hover {
    transform: rotate(0deg) scale(1.02);
}

/* ===== 功能亮点 ===== */
.features {
    padding: 50px 0 30px;
    background: #fff;
}
.section-title {
    text-align: center;
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-dark);
}
.section-sub {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 32px;
    font-size: 15px;
}
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}
.feature-card {
    background: var(--bg-gray);
    padding: 28px 22px;
    border-radius: var(--radius);
    text-align: center;
    transition: var(--transition);
    border: 1px solid transparent;
}
.feature-card:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow);
    transform: translateY(-4px);
}
.feature-card .icon {
    font-size: 40px;
    margin-bottom: 12px;
    display: block;
}
.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 6px;
}
.feature-card p {
    color: var(--text-muted);
    font-size: 14px;
}

/* ===== 截图区 ===== */
.screenshots {
    padding: 40px 0 50px;
    background: var(--bg-gray);
}
.screenshots-wrapper {
    position: relative;
    overflow: hidden;
}
.screenshots-scroll {
    display: flex;
    gap: 16px;
    overflow-x: auto;
    padding: 12px 4px 20px;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}
.screenshots-scroll::-webkit-scrollbar {
    display: none;
}
.screenshots-scroll .screenshot-item {
    flex: 0 0 180px;
    scroll-snap-align: start;
    border-radius: var(--radius-sm);
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    background: #fff;
    transition: var(--transition);
}
.screenshots-scroll .screenshot-item:hover {
    transform: scale(1.02);
}
.screenshots-scroll .screenshot-item img {
    width: 100%;
    height: 320px;
    object-fit: cover;
    background: #e2e8f0;
}
.screenshots-scroll .screenshot-item .label {
    padding: 8px 12px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    text-align: center;
}
.scroll-hint {
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}
.scroll-hint .arrow {
    display: inline-block;
    animation: scrollPulse 1.8s ease-in-out infinite;
}
@keyframes scrollPulse {
    0%,
    100% {
        transform: translateX(0);
        opacity: 1;
    }
    50% {
        transform: translateX(8px);
        opacity: 0.5;
    }
}

/* ===== 导航卡片区 ===== */
.nav-cards {
    padding: 40px 0 50px;
    background: #fff;
}
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 16px;
}
.card-item {
    background: var(--bg-gray);
    padding: 20px 16px;
    border-radius: var(--radius-sm);
    text-align: center;
    transition: var(--transition);
    border: 1px solid transparent;
    cursor: pointer;
}
.card-item:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow);
    transform: translateY(-3px);
}
.card-item .card-icon {
    font-size: 28px;
    display: block;
    margin-bottom: 6px;
}
.card-item .card-title {
    font-weight: 600;
    font-size: 15px;
    color: var(--text-dark);
}
.card-item .card-desc {
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* ===== FAQ 文章区 ===== */
.faq-section {
    padding: 40px 0 50px;
    background: var(--bg-gray);
}
.faq-list {
    max-width: 820px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.faq-item {
    background: #fff;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition);
}
.faq-item:hover {
    border-color: var(--primary-light);
}
.faq-question {
    padding: 16px 20px;
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #fff;
    transition: var(--transition);
    user-select: none;
}
.faq-question:hover {
    background: var(--primary-light);
}
.faq-question .toggle-icon {
    font-size: 20px;
    transition: var(--transition);
    color: var(--text-muted);
}
.faq-item.active .faq-question .toggle-icon {
    transform: rotate(180deg);
    color: var(--primary);
}
.faq-answer {
    padding: 0 20px 20px;
    color: var(--text-muted);
    font-size: 15px;
    display: none;
    line-height: 1.8;
}
.faq-item.active .faq-answer {
    display: block;
}
.faq-answer a {
    color: var(--primary);
    font-weight: 500;
}
.faq-answer a:hover {
    text-decoration: underline;
}

/* ===== 底部 ===== */
.footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 40px 0 20px;
}
.footer .container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.footer-top {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 20px;
}
.footer-brand {
    font-size: 18px;
    font-weight: 700;
    color: #fff;
}
.footer-brand span {
    color: var(--primary);
}
.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 16px 24px;
}
.footer-links a {
    color: #94a3b8;
    font-size: 14px;
    transition: var(--transition);
}
.footer-links a:hover {
    color: #fff;
}
.footer-disclaimer {
    background: rgba(255, 255, 255, 0.04);
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--primary);
    font-size: 14px;
    line-height: 1.7;
    color: #cbd5e1;
}
.footer-disclaimer strong {
    color: #fff;
}
.footer-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 16px 28px;
    font-size: 14px;
    color: #94a3b8;
    padding: 12px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.footer-stats .stat-item {
    display: flex;
    align-items: center;
    gap: 6px;
}
.footer-stats .stat-item .num {
    color: #fff;
    font-weight: 700;
    font-size: 16px;
}
.footer-copy {
    text-align: center;
    font-size: 13px;
    color: #64748b;
    padding-top: 10px;
}
.footer-copy a {
    color: #94a3b8;
}
.footer-copy a:hover {
    color: #fff;
}

/* ===== 悬浮下载按钮 ===== */
.float-download {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
    border-top: 1px solid var(--border-color);
    padding: 10px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    z-index: 999;
    transform: translateY(100%);
    opacity: 0;
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.4s ease;
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.08);
}
.float-download.show {
    transform: translateY(0);
    opacity: 1;
}
.float-download .float-info {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 1;
    min-width: 0;
}
.float-download .float-info img {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: var(--primary);
    object-fit: cover;
    flex-shrink: 0;
}
.float-download .float-info .float-text {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-dark);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.float-download .float-info .float-text small {
    font-weight: 400;
    color: var(--text-muted);
    font-size: 12px;
    display: block;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.float-download .float-btns {
    display: flex;
    gap: 8px;
    flex-shrink: 0;
}
.float-download .float-btns .btn {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: 30px;
}
.float-download .float-btns .btn-android {
    background: #3ddc84;
    color: #1a1a1a;
}
.float-download .float-btns .btn-ios {
    background: #1a1a1a;
    color: #fff;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(12px);
        padding: 12px 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
        gap: 2px;
    }
    .nav-links.open {
        display: flex;
    }
    .nav-links li a {
        padding: 10px 14px;
        font-size: 15px;
        width: 100%;
    }
    .nav-links li a.download-nav {
        background: var(--primary);
        color: #fff;
        text-align: center;
    }
    .hero {
        padding: 28px 0 36px;
    }
    .hero .container {
        flex-direction: column;
        gap: 20px;
    }
    .hero-right {
        flex: 0 0 auto;
        order: -1;
    }
    .hero-right img {
        max-width: 160px;
    }
    .hero-app-icon .app-name {
        font-size: 22px;
    }
    .hero-app-icon img {
        width: 64px;
        height: 64px;
    }
    .hero-buttons .btn {
        padding: 10px 20px;
        font-size: 14px;
    }
    .features-grid {
        grid-template-columns: 1fr 1fr;
    }
    .cards-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    }
    .screenshots-scroll .screenshot-item {
        flex: 0 0 140px;
    }
    .screenshots-scroll .screenshot-item img {
        height: 250px;
    }
    .footer-top {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    .footer-links {
        justify-content: center;
    }
    .float-download {
        padding: 8px 12px;
    }
    .float-download .float-info .float-text {
        font-size: 13px;
    }
    .float-download .float-btns .btn {
        padding: 6px 14px;
        font-size: 12px;
    }
    .float-download .float-info img {
        width: 34px;
        height: 34px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 12px;
    }
    .hero-app-icon .app-name {
        font-size: 20px;
    }
    .hero-app-icon .app-name small {
        font-size: 14px;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .cards-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .screenshots-scroll .screenshot-item {
        flex: 0 0 120px;
    }
    .screenshots-scroll .screenshot-item img {
        height: 210px;
    }
    .footer-stats {
        flex-direction: column;
        align-items: center;
        gap: 8px;
    }
    .section-title {
        font-size: 22px;
    }
    .float-download .float-btns .btn {
        padding: 6px 12px;
        font-size: 11px;
    }
    .float-download .float-info .float-text {
        font-size: 12px;
    }
}

@media (min-width: 769px) {
    .nav-links {
        display: flex !important;
    }
    .float-download .float-btns .btn {
        min-width: 90px;
    }
}