:root {
    /* 亮色主题配色 */
    --bg: #ffffff;
    --card: #ffffff;
    --accent1: #6c5ce7;
    --accent2: #a29bfe;
    --text: #2d3436;
    --text-muted: #636e72;
    --border: #e0e6ed;
    --radius: 16px;
    --maxw: 1200px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.12);
}

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

html, body {
    height: 100%;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Noto Sans SC', 'PingFang SC', 'Microsoft Yahei', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 容器 */
.inner {
    width: 100%;
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 20px;
}

/* 顶部导航栏 */
.topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
}

.topbar .inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: inherit;
}

.brand-logo {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    padding: 6px;
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
}

.brand-title {
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--text);
}

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

.icon-btn, .menu-btn {
    background: transparent;
    border: 1px solid var(--border);
    font-size: 18px;
    padding: 8px;
    border-radius: 10px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.download-small {
    display: none;
    text-decoration: none;
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
    color: #fff;
    padding: 10px 20px;
    border-radius: 10px;
    font-weight: 600;
    font-size: 0.9rem;
}

/* 移动端导航面板 */
.navpanel {
    display: none;
    padding: 20px;
    background: var(--card);
    border-top: 1px solid var(--border);
    box-shadow: var(--shadow);
}

.navpanel.open {
    display: block;
}

.navpanel a {
    display: block;
    padding: 14px 0;
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    border-bottom: 1px solid var(--border);
}

.navpanel a:last-child {
    border-bottom: none;
}

.navpanel a.download-cta {
    margin-top: 10px;
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
    color: #fff;
    text-align: center;
    padding: 14px;
    border-radius: 12px;
    font-weight: 600;
}

/* 主内容区域 */
main {
    min-height: calc(100vh - 80px);
}

/* Hero 区域 */
.hero {
    padding: 60px 0 40px;
}

.hero-inner {
    display: flex;
    flex-direction: column;
    gap: 40px;
    align-items: center;
}

.hero-text {
    text-align: center;
    max-width: 600px;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tag {
    color: var(--accent1);
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: 16px;
}

.lead {
    color: var(--text-muted);
    font-size: 1.1rem;
    margin-bottom: 30px;
    line-height: 1.7;
}

.cta-row {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    padding: 14px 28px;
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    min-width: 140px;
}

.primary {
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
    color: #fff;
    box-shadow: var(--shadow);
}

.primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.ghost {
    border: 2px solid var(--border);
    color: var(--text);
    background: transparent;
}

.ghost:hover {
    border-color: var(--accent1);
    color: var(--accent1);
}

.tiny-list {
    list-style: none;
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    color: var(--text-muted);
    font-size: 0.95rem;
}

.tiny-list li {
    display: flex;
    align-items: center;
    gap: 6px;
}

/* 设备模拟 */
.hero-visual {
    display: flex;
    justify-content: center;
}

.device {
    width: 280px;
    height: 560px;
    border-radius: 40px;
    background: linear-gradient(180deg, #fff, #f7f4ff);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    border: 12px solid #1a1a1a;
}

.device img {
    width: 85%;
    height: auto;
    border-radius: 8px;
}

.screen-glow {
    position: absolute;
    inset: auto 10% 4% 10%;
    height: 20px;
    background: radial-gradient(closest-side, rgba(108, 92, 231, 0.15), transparent);
    filter: blur(8px);
}

/* 通用区块样式 */
.section {
    padding: 60px 0;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 16px;
    color: var(--text);
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 40px;
}

/* 功能区块 */
.features {
    background: #f8f9ff;
}

.features .grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    margin-top: 40px;
}

.feature {
    background: var(--card);
    padding: 30px 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: transform 0.3s ease;
}

.feature:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.feature strong {
    display: block;
    font-size: 1.2rem;
    margin-bottom: 12px;
    color: var(--text);
}

.feature p {
    color: var(--text-muted);
    line-height: 1.6;
}

/* 轮播图 */
.carousel {
    margin-top: 40px;
    position: relative;
    overflow: hidden;
    border-radius: var(--radius);
    background: var(--card);
    box-shadow: var(--shadow);
}

.slides {
    display: flex;
    transition: transform 0.5s cubic-bezier(0.2, 0.9, 0.2, 1);
}

.slide {
    min-width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
}

.placeholder-img {
    width: 100%;
    max-width: 300px;
    height: auto;
    border-radius: 12px;
}

.dots {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin: 24px 0;
}

.dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--border);
    border: none;
    padding: 0;
    cursor: pointer;
    transition: background 0.3s ease;
}

.dot.active {
    background: linear-gradient(135deg, var(--accent1), var(--accent2));
}

/* 常见问题 */
.faq {
    background: #f8f9ff;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq details {
    background: var(--card);
    margin: 16px 0;
    padding: 0;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.faq summary {
    padding: 24px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1.1rem;
    list-style: none;
    position: relative;
}

.faq summary::-webkit-details-marker {
    display: none;
}

.faq summary:after {
    content: '+';
    position: absolute;
    right: 24px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.5rem;
    color: var(--accent1);
}

.faq details[open] summary:after {
    content: '-';
}

.faq details p {
    padding: 0 24px 24px;
    color: var(--text-muted);
    line-height: 1.7;
    border-top: 1px solid var(--border);
    margin-top: 0;
    padding-top: 20px;
}

/* 页脚 */
.site-footer {
    background: var(--card);
    padding: 40px 0;
    border-top: 1px solid var(--border);
    margin-top: 40px;
}

.footer-inner {
    display: flex;
    flex-direction: column;
    gap: 20px;
    align-items: center;
    text-align: center;
    color: var(--text-muted);
}

.footer-inner a {
    color: var(--text-muted);
    text-decoration: none;
}

.footer-inner a:hover {
    color: var(--accent1);
}

/* 响应式设计 */
@media (min-width: 768px) {
    .inner {
        padding: 0 30px;
    }

    .hero {
        padding: 80px 0 60px;
    }

    .hero-inner {
        flex-direction: row;
        justify-content: space-between;
        text-align: left;
        gap: 60px;
    }

    .hero-text {
        text-align: left;
        flex: 1;
    }

    .hero-visual {
        flex: 0 0 auto;
    }

    .cta-row {
        justify-content: flex-start;
    }

    .tiny-list {
        justify-content: flex-start;
    }

    .features .grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .menu-btn {
        display: none;
    }

    .download-small {
        display: inline-flex;
    }

    .navpanel {
        display: flex !important;
        position: static;
        background: transparent;
        box-shadow: none;
        border: none;
        padding: 0;
        gap: 30px;
    }

    .navpanel a {
        display: inline-flex;
        padding: 0;
        border: none;
        color: var(--text);
        font-weight: 500;
    }

    .navpanel a.download-cta {
        display: none;
    }

    .footer-inner {
        flex-direction: row;
        justify-content: space-between;
        text-align: left;
    }
}

@media (min-width: 1024px) {
    h1 {
        font-size: 3rem;
    }

    .section-title {
        font-size: 2.5rem;
    }

    .features .grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .device {
        width: 320px;
        height: 640px;
    }
}

@media (min-width: 1200px) {
    .hero-inner {
        gap: 80px;
    }
}

/* 暗色主题 - 默认禁用 */
:root.dark {
    --bg: #0f1419;
    --card: #1a1f2b;
    --text: #e1e7ef;
    --text-muted: #8a94a6;
    --border: #2a3142;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.4);
}

:root.dark .features,
:root.dark .faq {
    background: #0a0e14;
}

:root.dark .brand-title {
    color: var(--text);
}