:root {
    --bg: #f6f7fb;
    --bg-soft: #ffffff;
    --card: #ffffff;
    --accent: #e54242;
    --accent-strong: #ff6b5d;
    --text: #1b1b24;
    --muted: #6f7282;
    --line: rgba(24, 26, 40, 0.08);
    --shadow: 0 24px 50px rgba(30, 33, 52, 0.12);
    --radius: 22px;
    --max-width: 1040px;
    font-size: 16px;
}

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

body {
    font-family: "Alibaba PuHuiTi", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: radial-gradient(circle at top, rgba(255, 106, 106, 0.18), transparent 55%),
        radial-gradient(circle at 90% 10%, rgba(255, 201, 201, 0.3), transparent 45%),
        linear-gradient(180deg, #f8f9fe 0%, #f1f3fb 60%, #eef1f8 100%);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
}

a {
    color: inherit;
    text-decoration: none;
}

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

.page {
    width: 100%;
    overflow: hidden;
}

.nav {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 32px 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 14px;
}

.brand img {
    background: #ffffff;
    border-radius: 14px;
    padding: 6px;
    border: 1px solid rgba(229, 66, 66, 0.3);
    box-shadow: 0 12px 24px rgba(229, 66, 66, 0.18);
}

.brand-title {
    font-size: 1.4rem;
    font-weight: 700;
}

.brand-sub {
    font-size: 0.85rem;
    color: var(--muted);
}

.nav-links {
    display: none;
    gap: 18px;
    font-size: 0.95rem;
    color: var(--muted);
}

.nav-links a {
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--text);
}

.nav-cta {
    display: none;
}

.hero {
    padding-bottom: 80px;
}

.hero-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
    align-items: center;
    text-align: center;
}

.hero-tag {
    display: inline-flex;
    padding: 8px 18px;
    border-radius: 999px;
    background: rgba(255, 66, 66, 0.2);
    color: var(--accent);
    font-weight: 600;
}

.hero h1 {
    font-size: clamp(2.4rem, 5vw, 3.8rem);
    line-height: 1.1;
    margin: 18px 0;
}

.hero-desc {
    color: var(--muted);
    font-size: 1.05rem;
    margin-bottom: 20px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 28px;
    justify-content: center;
}

.btn {
    padding: 14px 26px;
    border-radius: 999px;
    font-weight: 700;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    text-align: center;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background: linear-gradient(120deg, var(--accent), var(--accent-strong));
    color: #ffffff;
    box-shadow: 0 16px 30px rgba(229, 66, 66, 0.25);
}

.btn-ghost {
    border: 1px solid var(--line);
    color: var(--text);
}

.btn-dark {
    background: #1f1d36;
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text);
}

.hero-badges {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
    justify-content: center;
    align-items: stretch;
}

.hero-badges div {
    background: var(--card);
    padding: 12px 10px;
    border-radius: 16px;
    border: 1px solid var(--line);
    min-width: 0;
}

.hero-badges h4 {
    font-size: 1.3rem;
}

.hero-badges span {
    color: var(--muted);
    font-size: 0.85rem;
}

.hero-device {
    display: flex;
    justify-content: center;
}

.device-card {
    width: min(360px, 85vw);
    background: var(--card);
    border-radius: 32px;
    padding: 18px;
    border: 1px solid rgba(229, 66, 66, 0.18);
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.device-card::after {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at top, rgba(229, 66, 66, 0.18), transparent 55%);
    pointer-events: none;
}

.carousel {
    position: relative;
    width: 100%;
    aspect-ratio: 9 / 16;
    max-width: 240px;
    margin: 0 auto;
    overflow: hidden;
    border-radius: 18px;
}

.carousel img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0;
    transition: opacity 0.6s ease;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
}

.carousel img.active {
    opacity: 1;
}

.device-body {
    display: grid;
    gap: 12px;
}

.device-footer {
    margin-top: 22px;
    padding: 16px;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.05);
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--muted);
}

.stats {
    max-width: var(--max-width);
    margin: -10px auto 70px;
    padding: 0 24px;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
    text-align: center;
}

.stat-card {
    background: var(--bg-soft);
    border-radius: var(--radius);
    padding: 24px;
    border: 1px solid var(--line);
}

.stat-card h3 {
    margin-bottom: 10px;
    font-size: 1.2rem;
}

.stat-card p {
    color: var(--muted);
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
}

.section-title p {
    color: var(--accent);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.85rem;
}

.section-title h2 {
    font-size: clamp(2rem, 4vw, 2.6rem);
    margin-top: 12px;
}

.features,
.faq {
    max-width: var(--max-width);
    margin: 0 auto 70px;
    padding: 0 24px;
}

.feature-grid {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    text-align: center;
}

.feature-grid article {
    background: var(--bg-soft);
    border-radius: var(--radius);
    padding: 18px;
    border: 1px solid var(--line);
}

.feature-grid h3 {
    margin-bottom: 10px;
    font-size: 1rem;
}

.feature-grid p {
    color: var(--muted);
}

.library-card span {
    color: var(--accent);
    font-weight: 600;
}

.faq-list {
    display: grid;
    gap: 16px;
}

.faq-item {
    background: var(--bg-soft);
    border-radius: 20px;
    border: 1px solid var(--line);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    background: transparent;
    border: none;
    color: var(--text);
    padding: 16px 20px;
    font-size: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding: 0 24px;
    color: var(--muted);
}

.faq-item.active .faq-answer {
    max-height: 140px;
    padding-bottom: 18px;
}

.footer {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 32px 24px 50px;
    border-top: 1px solid var(--line);
    display: grid;
    gap: 18px;
    text-align: center;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 18px;
    color: var(--muted);
    justify-content: center;
}

.footer-copy {
    color: var(--muted);
    font-size: 0.85rem;
}

@media (max-width: 900px) {
    .nav {
        flex-direction: column;
        align-items: center;
    }

    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}

@media (max-width: 640px) {
    :root {
        font-size: 15px;
    }

    .hero-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .hero-badges {
        flex-direction: column;
    }
}