/* CSS Variables for Design System */
:root {
    --color-primary: #0A1931;
    --color-secondary: #183A5D;
    --color-accent: #D6B656;
    --color-text-primary: #F0F4F8;
    --color-text-secondary: #A9B4C2;
    --color-text-button: #0A1931;
    --color-shadow: rgba(0, 0, 0, 0.25);
    --color-shadow-gold: rgba(214, 182, 86, 0.3);
    
    --font-primary: 'PingFang SC', 'Microsoft YaHei', sans-serif;
    --font-weight-regular: 400;
    --font-weight-semi-bold: 600;
    --font-weight-bold: 700;
    
    --border-radius-small: 8px;
    --border-radius-medium: 16px;
    --border-radius-large: 24px;
    --border-radius-pill: 50px;
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    --container-max-width: 1200px;
    --container-padding: 1rem;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    font-weight: var(--font-weight-regular);
    line-height: 1.7;
    color: var(--color-text-primary);
    background: linear-gradient(180deg, var(--color-secondary) 0%, var(--color-primary) 100%);
    min-height: 100vh;
}

/* Container */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-bold);
    line-height: 1.2;
    margin-bottom: var(--spacing-sm);
}

h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
}

h2 {
    font-size: 1.8rem;
    margin-bottom: var(--spacing-md);
    position: relative;
}

h3 {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-sm);
}

p {
    margin-bottom: var(--spacing-sm);
}

/* Section Title Styling */
.section__title {
    text-align: center;
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-lg);
    position: relative;
}

.section__title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background-color: var(--color-accent);
    margin: var(--spacing-sm) auto 0;
    border-radius: 2px;
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: 16px 32px;
    font-size: 1.1rem;
    font-weight: var(--font-weight-bold);
    text-decoration: none;
    text-align: center;
    border-radius: var(--border-radius-pill);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s ease;
    letter-spacing: 0.5px;
    min-width: 200px;
}

.btn--primary {
    background-color: var(--color-accent);
    color: var(--color-text-button);
    box-shadow: 0 4px 15px var(--color-shadow);
}

.btn--primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--color-shadow-gold);
}

.btn--outline {
    background-color: transparent;
    color: var(--color-accent);
    border-color: var(--color-accent);
}

.btn--outline:hover {
    background-color: var(--color-accent);
    color: var(--color-text-button);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--color-shadow-gold);
}

.btn--large {
    padding: 20px 40px;
    font-size: 1.2rem;
    min-width: 280px;
}

/* Card Styles */
.card {
    background-color: rgba(24, 58, 93, 0.5);
    padding: var(--spacing-md);
    border-radius: var(--border-radius-medium);
    border: 1px solid rgba(214, 182, 86, 0.2);
    box-shadow: 0 10px 30px var(--color-shadow);
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px var(--color-shadow);
}

/* Icon Styles */
.icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    margin: 0 auto var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--color-text-button);
    font-weight: var(--font-weight-bold);
}

.icon--douyin {
    background: linear-gradient(135deg, #ff0050, #ff4081);
}

.icon--kuaishou {
    background: linear-gradient(135deg, #ff6900, #fcb045);
}

.icon--xiaohongshu {
    background: linear-gradient(135deg, #ff2442, #ff6b6b);
}

.icon--security {
    background: linear-gradient(135deg, #4CAF50, #8BC34A);
}

.icon--speed {
    background: linear-gradient(135deg, #2196F3, #03DAC6);
}

.icon--team {
    background: linear-gradient(135deg, #9C27B0, #E91E63);
}

.icon--privacy {
    background: linear-gradient(135deg, #FF9800, #FFC107);
}

.icon--douyin::after { content: "抖"; }
.icon--kuaishou::after { content: "快"; }
.icon--xiaohongshu::after { content: "红"; }
.icon--security::after { content: "🛡"; }
.icon--speed::after { content: "⚡"; }
.icon--team::after { content: "👥"; }
.icon--privacy::after { content: "🔒"; }

/* Hero Section */
.hero {
    padding: var(--spacing-xl) 0;
    text-align: center;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-primary) 100%);
}

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

.hero__title {
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--color-text-primary), var(--color-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero__subtitle {
    font-size: 1.2rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero__cta {
    margin-top: var(--spacing-md);
}

/* Services Section */
.services {
    padding: var(--spacing-xl) 0;
    background: rgba(10, 25, 49, 0.3);
}

.services__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.service-card {
    text-align: center;
    height: 100%;
    display: flex;
    flex-direction: column;
}

.service-card__icon {
    margin-bottom: var(--spacing-md);
}

.service-card__title {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
}

.service-card__description {
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
    flex-grow: 1;
}

.service-card__features {
    list-style: none;
    padding: 0;
    margin-top: auto;
}

.service-card__features li {
    position: relative;
    padding-left: 20px;
    margin-bottom: var(--spacing-xs);
    color: var(--color-text-secondary);
}

.service-card__features li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: var(--font-weight-bold);
}

/* Features Section */
.features {
    padding: var(--spacing-xl) 0;
}

.features__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.feature-card {
    text-align: center;
}

.feature-card__icon {
    margin-bottom: var(--spacing-md);
}

.feature-card__title {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-card__description {
    color: var(--color-text-secondary);
}

/* Pricing Section */
.pricing {
    padding: var(--spacing-xl) 0;
    background: rgba(10, 25, 49, 0.3);
}

.pricing__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.pricing-card {
    text-align: center;
    position: relative;
    display: flex;
    flex-direction: column;
}

.pricing-card--featured {
    border: 2px solid var(--color-accent);
    transform: scale(1.05);
}

.pricing-card__badge {
    position: absolute;
    top: -10px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--color-accent);
    color: var(--color-text-button);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--border-radius-pill);
    font-size: 0.9rem;
    font-weight: var(--font-weight-bold);
}

.pricing-card__header {
    margin-bottom: var(--spacing-md);
}

.pricing-card__title {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-md);
}

.pricing-card__price {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-accent);
    margin-bottom: var(--spacing-md);
}

.price-currency,
.price-period {
    font-size: 1rem;
    color: var(--color-text-secondary);
}

.pricing-card__features {
    list-style: none;
    padding: 0;
    margin-bottom: var(--spacing-lg);
    flex-grow: 1;
}

.pricing-card__features li {
    padding: var(--spacing-xs) 0;
    color: var(--color-text-secondary);
    border-bottom: 1px solid rgba(169, 180, 194, 0.1);
}

.pricing-card__features li:last-child {
    border-bottom: none;
}

/* Testimonials Section */
.testimonials {
    padding: var(--spacing-xl) 0;
}

.testimonials__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.testimonial-card__content {
    margin-bottom: var(--spacing-md);
}

.testimonial-card__quote {
    font-style: italic;
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    position: relative;
    padding-left: 30px;
}

.testimonial-card__quote::before {
    content: """;
    position: absolute;
    left: 0;
    top: -10px;
    font-size: 3rem;
    color: var(--color-accent);
    line-height: 1;
}

.testimonial-card__author {
    border-top: 1px solid rgba(214, 182, 86, 0.3);
    padding-top: var(--spacing-md);
}

.author-name {
    color: var(--color-text-primary);
    font-size: 1rem;
    margin-bottom: var(--spacing-xs);
}

.author-title {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
}

/* Final CTA Section */
.final-cta {
    padding: var(--spacing-xl) 0;
    background: linear-gradient(135deg, var(--color-secondary), var(--color-primary));
    text-align: center;
}

.final-cta__content {
    max-width: 800px;
    margin: 0 auto;
}

.final-cta__title {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--color-text-primary);
}

.final-cta__subtitle {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Footer */
.footer {
    padding: var(--spacing-md) 0;
    background-color: var(--color-primary);
    text-align: center;
}

.footer__text {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --container-padding: 1rem;
    }
    
    .hero__title {
        font-size: 2.5rem;
    }
    
    .section__title {
        font-size: 1.8rem;
    }
    
    .final-cta__title {
        font-size: 2rem;
    }
    
    .services__grid,
    .features__grid,
    .pricing__grid,
    .testimonials__grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-sm);
    }
    
    .pricing-card--featured {
        transform: none;
    }
    
    .btn {
        padding: 14px 28px;
        font-size: 1rem;
        min-width: 180px;
    }
    
    .btn--large {
        padding: 16px 32px;
        font-size: 1.1rem;
        min-width: 240px;
    }
    
    .hero {
        padding: var(--spacing-lg) 0;
        min-height: 80vh;
    }
    
    .pricing-card__price {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .hero__title {
        font-size: 2rem;
    }
    
    .section__title {
        font-size: 1.5rem;
    }
    
    .final-cta__title {
        font-size: 1.8rem;
    }
    
    .card {
        padding: var(--spacing-sm);
    }
    
    .btn {
        padding: 12px 24px;
        min-width: 160px;
    }
    
    .btn--large {
        padding: 14px 28px;
        min-width: 200px;
    }
}

/* Focus Styles for Accessibility */
.btn:focus-visible,
a:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* Animation for smooth interactions */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card {
    animation: fadeInUp 0.6s ease-out;
}

/* Print styles */
@media print {
    body {
        background: white !important;
        color: black !important;
    }
    
    .hero,
    .services,
    .features,
    .pricing,
    .testimonials,
    .final-cta {
        background: white !important;
    }
    
    .btn {
        border: 1px solid black !important;
        background: white !important;
        color: black !important;
    }
}