/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #ffffff;
    background-color: #000000;
    overflow-x: hidden;
    width: 100%;
    min-height: 100vh;
    position: relative;
}

html {
    overflow-x: hidden;
    width: 100%;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header Styles */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(0, 0, 0, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 1000;
    padding: 15px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-img {
    width: auto;
    height: 40px;
}

.logo-text {
    font-size: 24px;
    font-weight: bold;
    color: #ffffff;
}

.nav {
    display: flex;
    gap: 15px;
}

.nav-link {
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 25px;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.apple-download {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

.apple-download:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.android-download {
    color: #000000;
    background: #bcff2f;
    border-color: #bcff2f;
}

.android-download:hover {
    background: #bcff2f;
    transform: translateY(-2px);
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #000000 0%, #1a1a1a 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-content {
    display: flex;
    flex-direction: row;
    gap: 60px;
    align-items: center;
}

.hero-text {
    width: 65%;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    background: linear-gradient(135deg, #ffffff 0%, #cccccc 100%);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-description {
    font-size: 1.2rem;
    color: #cccccc;
    margin-bottom: 40px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 20px;
}

.btn {
    padding: 15px 30px;
    text-decoration: none;
    border-radius: 30px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    display: inline-block;
    border: none;
    cursor: pointer;
    text-align: center;
}

.hero-buttons .btn {
  width: 200px;
}

.btn-primary {
    background: #bcff2f;
    color: #000000;
}

.btn-primary:hover {
    background: #bcff2f;
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(76, 175, 80, 0.3);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.9);
    color: #000000;
}

.btn-secondary:hover {
    background: #ffffff;
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(255, 255, 255, 0.2);
}

.hero-video {
    text-align: center;
    width: 35%;
}

.mobile-mockup {
    max-width: 100%;
    height: auto;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

/* Download Explanation Section */
.download-explanation {
    padding: 80px 0;
    background: #111111;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: 30px;
    color: #ffffff;
}

.section-subtitle {
    font-size: 1.1rem;
    color: #cccccc;
    text-align: center;
    margin-bottom: 50px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.explanation-text p {
    font-size: 1.1rem;
    color: #cccccc;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.8;
    margin-bottom: 25px;
}

/* OKX Spot Trading Section */
.okx-spot-trading {
    padding: 80px 0;
    background: linear-gradient(135deg, #1a4d2e 0%, #2d5016 100%);
}

.spot-trading-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.spot-trading-title {
    font-size: 2.5rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: #ffffff;
}

.spot-trading-description {
    font-size: 1.1rem;
    color: #e8f5e8;
    line-height: 1.8;
}

.trading-interface {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 15px;
    padding: 30px;
    border: 1px solid rgba(76, 175, 80, 0.3);
}

.trading-chart {
    height: 200px;
    background: linear-gradient(45deg, #bcff2f, #81C784);
    border-radius: 10px;
    position: relative;
    overflow: hidden;
}

.trading-chart::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 50"><path d="M0,25 Q25,5 50,25 T100,25" stroke="rgba(255,255,255,0.5)" stroke-width="2" fill="none"/></svg>') center/cover;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: #000000;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.feature-card {
    background: rgba(255, 255, 255, 0.02);
    border-radius: 20px;
    padding: 40px 30px;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 18px;
    padding: 2px;
    background: linear-gradient(135deg, var(--border-color), transparent);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: exclude;
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask-composite: exclude;
}

.feature-green {
    --border-color: #bcff2f;
}

.feature-blue {
    --border-color: #2196F3;
}

.feature-orange {
    --border-color: #FF9800;
}

.feature-purple {
    --border-color: #9C27B0;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.feature-icon {
    width: 60%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon img {
    width: 100%;
    object-fit: contain;
}

.feature-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #ffffff;
}

.feature-description {
    color: #cccccc;
    line-height: 1.6;
}

/* Download CTA */
.download-cta {
    padding: 80px 0;
    background: linear-gradient(135deg, #1a1a1a 0%, #2d2d2d 100%);
    text-align: center;
}

.cta-title {
    font-size: 2.5rem;
    font-weight: 600;
    margin-bottom: 40px;
    color: #ffffff;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
}

/* Security Classroom */
.security-classroom {
    padding: 80px 0;
    background: #111111;
}

.security-features {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    margin-top: 50px;
}

.security-feature {
    text-align: center;
    padding: 30px 20px;
    border-radius: 15px;
    transition: all 0.3s ease;
    width: calc(25% - 23px); /* 4个元素一行，考虑间距 */
}

.security-icon {
    width: 200px;
    margin: 0 auto 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.security-icon img {
    width: 100%;
    object-fit: contain;
}

.security-title {
    font-size: 1.1rem;
    font-weight: 500;
    color: #ffffff;
}

/* Footer */
.footer {
    background: #0a0a0a;
    padding: 60px 0 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.footer-logo {
    height: 45px;
    width: fit-content;
}

.footer-brand-text {
    font-size: 1.1rem;
    color: #cccccc;
}

.btn-register {
    background: #bcff2f;
    color: #000000;
    align-self: flex-start;
}

.btn-register:hover {
    background: #bcff2f;
    transform: translateY(-2px);
}

.footer-columns {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 30px;
}

.footer-column-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #ffffff;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: #999999;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #bcff2f;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.copyright {
    color: #666666;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 15px;
        overflow: hidden;
        max-width: 100%;
    }

    .header {
        padding: 10px 0;
    }

    .header-content {
        flex-direction: row;
        justify-content: space-between;
        gap: 10px;
    }

    .header .logo-img {
        height: 28px;
    }

    .nav {
        gap: 8px;
    }

    .nav-link {
        padding: 6px 8px;
        font-size: 0.85rem;
    }

    .hero {
        padding: 100px 0 60px;
    }

    .hero-content {
        flex-direction: column;
        gap: 40px;
        text-align: center;
    }

    .hero-text {
      width: 100%;
    }

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

    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }

    .hero-video {
        width: 100%;
        padding: 0 12px;
    }

    .spot-trading-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .security-features {
        gap: 20px;
    }

    .security-feature {
        width: calc(50% - 10px); /* 2个元素一行，考虑间距 */
    }

    .security-icon {
        width: 150px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .footer-columns {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }

    .section-title {
        font-size: 2rem;
    }

    .spot-trading-title,
    .cta-title {
        font-size: 2rem;
    }

    .footer-columns {
      display: none;
    }
}


/* 防止animate.css动画导致页面溢出 */
.animate__animated {
    transform-style: preserve-3d;
    backface-visibility: hidden;
    will-change: transform, opacity;
}