*,
*::before,
*::after {
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    padding: 0;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    background: #0a0a0a;
    color: #fff;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a {
    color: #d4af37;
    text-decoration: none;
    transition: opacity 0.2s;
}

a:hover {
    opacity: 0.85;
}

.container {
    width: 100%;
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(10, 10, 10, 0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(212, 175, 55, 0.12);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #fff;
}

.brand-logo {
    width: 36px;
    height: 36px;
    border-radius: 8px;
}

.brand-name {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 1px;
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 28px;
}

.nav-link {
    color: #999;
    font-size: 15px;
}

.nav-link:hover,
.nav-link.active {
    color: #d4af37;
    opacity: 1;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px;
    height: 36px;
    padding: 0;
    border: none;
    background: transparent;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: #d4af37;
    transition: transform 0.2s;
}

/* Hero */
.hero {
    padding: 72px 0 48px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    top: -120px;
    left: 50%;
    transform: translateX(-50%);
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(212, 175, 55, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-grid {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 48px;
}

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

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

.hero-logo {
    width: 72px;
    height: 72px;
    border-radius: 16px;
    margin-bottom: 20px;
}

.hero-title {
    font-size: 42px;
    font-weight: 700;
    margin: 0 0 12px;
    background: linear-gradient(135deg, #f5d78e, #d4af37);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-slogan {
    font-size: 24px;
    color: #f5d78e;
    margin: 0 0 8px;
    font-weight: 600;
    letter-spacing: 2px;
}

.hero-sub {
    font-size: 16px;
    color: #d4af37;
    margin: 0 0 20px;
    font-style: italic;
    opacity: 0.85;
}

.hero-desc {
    font-size: 16px;
    color: #999;
    margin: 0;
    max-width: 480px;
    line-height: 1.8;
}

.hero-visual {
    max-width: 320px;
    width: 100%;
    border-radius: 16px;
}

/* Features */
.section {
    padding: 64px 0;
}

.section-title {
    text-align: center;
    font-size: 28px;
    font-weight: 600;
    margin: 0 0 16px;
    color: #fff;
}

.section-desc {
    text-align: center;
    font-size: 15px;
    color: #888;
    margin: 0 auto 40px;
    max-width: 560px;
    line-height: 1.8;
}

.features {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 24px;
}

.feature-card {
    background: #1e1e1e;
    border: 1px solid rgba(212, 175, 55, 0.1);
    border-radius: 16px;
    padding: 28px 20px;
    text-align: center;
    transition: border-color 0.2s, transform 0.2s;
}

.feature-card:hover {
    border-color: rgba(212, 175, 55, 0.35);
    transform: translateY(-2px);
}

.feature-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 16px;
    border-radius: 12px;
    background: linear-gradient(135deg, #f5d78e, #c9a03c);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    color: #1a1a1a;
    font-weight: 700;
}

.feature-card h3 {
    font-size: 17px;
    margin: 0 0 10px;
    color: #fff;
}

.feature-card p {
    font-size: 14px;
    color: #999;
    margin: 0;
    line-height: 1.7;
}

/* Showcase */
.showcase {
    background: #111;
    border-top: 1px solid rgba(212, 175, 55, 0.08);
}

.screens-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.screen-item {
    text-align: center;
}

.phone-frame {
    background: #1a1a1a;
    border: 1px solid rgba(212, 175, 55, 0.15);
    border-radius: 20px;
    padding: 8px;
    overflow: hidden;
    transition: border-color 0.2s, transform 0.2s;
}

.phone-frame:hover {
    border-color: rgba(212, 175, 55, 0.4);
    transform: translateY(-4px);
}

.phone-frame img {
    width: 100%;
    display: block;
    border-radius: 14px;
}

.screen-label {
    margin: 14px 0 0;
    font-size: 14px;
    color: #d4af37;
    font-weight: 500;
}

/* About */
.about {
    background: #111;
    border-top: 1px solid rgba(212, 175, 55, 0.08);
    border-bottom: 1px solid rgba(212, 175, 55, 0.08);
}

.about-text {
    max-width: 720px;
    margin: 0 auto;
    text-align: center;
    font-size: 16px;
    color: #bbb;
    line-height: 1.9;
}

/* Protocol page */
.protocol-page {
    padding: 48px 0 72px;
}

.protocol-card {
    background: #f8f8f8;
    color: #333;
    border-radius: 16px;
    padding: 40px 36px;
    max-width: 860px;
    margin: 0 auto;
}

.protocol-card h1 {
    font-size: 26px;
    margin: 0 0 24px;
    color: #1a1a1a;
    text-align: center;
}

.protocol-body {
    font-size: 15px;
    line-height: 1.9;
    word-break: break-word;
}

.protocol-body p {
    margin: 0 0 14px;
}

.protocol-empty {
    text-align: center;
    color: #999;
    padding: 40px 0;
}

/* Footer */
.site-footer {
    padding: 36px 0;
    border-top: 1px solid rgba(212, 175, 55, 0.1);
    text-align: center;
}

.footer-links {
    margin-bottom: 12px;
}

.footer-links a {
    color: #999;
    font-size: 14px;
}

.footer-links a:hover {
    color: #d4af37;
}

.footer-links .sep {
    color: #444;
    margin: 0 10px;
}

.footer-copy,
.footer-contact {
    font-size: 13px;
    color: #666;
    margin: 6px 0;
}

.footer-copy a {
    color: #666;
    margin-left: 8px;
}

/* Responsive */
@media (max-width: 900px) {
    .hero-grid {
        flex-direction: column;
        text-align: center;
    }

    .hero-content {
        text-align: center;
    }

    .hero-desc {
        margin: 0 auto;
    }

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

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

@media (max-width: 640px) {
    .nav-toggle {
        display: flex;
    }

    .site-nav {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        flex-direction: column;
        gap: 0;
        background: rgba(10, 10, 10, 0.98);
        border-bottom: 1px solid rgba(212, 175, 55, 0.12);
        padding: 12px 0;
    }

    .site-nav.open {
        display: flex;
    }

    .site-nav .nav-link {
        padding: 12px 20px;
        width: 100%;
    }

    .header-inner {
        position: relative;
    }

    .hero {
        padding: 48px 0 32px;
    }

    .hero-title {
        font-size: 32px;
    }

    .hero-slogan {
        font-size: 20px;
    }

    .hero-visual {
        max-width: 260px;
    }

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

    .screens-grid {
        grid-template-columns: 1fr;
        max-width: 280px;
        margin: 0 auto;
    }

    .protocol-card {
        padding: 28px 20px;
    }
}