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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    overflow-x: hidden;
}

/* Animated Background */
.animated-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.floating-card {
    position: absolute;
    width: 60px;
    height: 80px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    animation: float 6s ease-in-out infinite;
}

.floating-card:nth-child(1) {
    top: 20%;
    left: 10%;
    animation-delay: 0s;
}

.floating-card:nth-child(2) {
    top: 60%;
    left: 80%;
    animation-delay: 2s;
}

.floating-card:nth-child(3) {
    top: 80%;
    left: 20%;
    animation-delay: 4s;
}

.floating-card:nth-child(4) {
    top: 30%;
    left: 70%;
    animation-delay: 1s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
        opacity: 0.7;
    }
    50% {
        transform: translateY(-20px) rotate(180deg);
        opacity: 1;
    }
}

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

/* Header */
.header {
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar {
    padding: 1rem 0;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.logo h1 {
    color: #ffd700;
    font-size: 1.8rem;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: #ffd700;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #ffd700;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.auth-buttons {
    display: flex;
    gap: 1rem;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    display: inline-block;
    text-align: center;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(45deg, #ffd700, #ffed4e);
    color: #333;
    box-shadow: 0 4px 15px rgba(255, 215, 0, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 215, 0, 0.4);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid #ffd700;
}

.btn-secondary:hover {
    background: #ffd700;
    color: #333;
}

.btn-login {
    background: transparent;
    color: white;
    border: 2px solid #4CAF50;
}

.btn-login:hover {
    background: #4CAF50;
    color: white;
}

.btn-register {
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    box-shadow: 0 4px 15px rgba(255, 107, 107, 0.3);
}

.btn-register:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 107, 0.4);
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    text-align: center;
    color: white;
}

.hero-content h2 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    color: #ffd700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    animation: fadeInUp 1s ease;
}

.hero-content p {
    font-size: 1.3rem;
    margin-bottom: 2rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
    animation: fadeInUp 1s ease 0.2s both;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease 0.4s both;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: rgba(255, 255, 255, 0.95);
    color: #333;
}

.features h3 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e3c72;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h4 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e3c72;
}

/* Registration Steps */
.registration-steps {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.registration-steps h3 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #ffd700;
}

.steps-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.step {
    background: rgba(255, 255, 255, 0.1);
    padding: 2rem;
    border-radius: 15px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: transform 0.3s ease;
}

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

.step-number {
    width: 50px;
    height: 50px;
    background: #ffd700;
    color: #333;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 1rem;
}

.step h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #ffd700;
}

.step p {
    line-height: 1.7;
}

/* Game Categories */
.game-categories {
    padding: 80px 0;
    background: white;
    color: #333;
}

.game-categories h3 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #1e3c72;
}

.game-categories > .container > p {
    text-align: center;
    font-size: 1.2rem;
    margin-bottom: 3rem;
    color: #666;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    justify-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.category-card {
    width: 300px;
    max-width: 100%;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    overflow: hidden;
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.category-card img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: transform 0.3s ease;
    border-radius: 15px 15px 0 0;
}

.category-card:hover img {
    transform: scale(1.05);
}

/* 确保图片容器保持一致的外观 */
.category-card picture {
    display: block;
    width: 100%;
    height: 300px;
    overflow: hidden;
    border-radius: 15px 15px 0 0;
}

.category-card h4 {
    padding: 1.5rem 1.5rem 1rem;
    font-size: 1.3rem;
    color: #1e3c72;
}

.category-card p {
    padding: 0 1.5rem 1.5rem;
    color: #666;
    line-height: 1.6;
}

/* Call to Action */
.cta {
    padding: 80px 0;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    color: white;
    text-align: center;
}

.cta h3 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: #ffd700;
}

.cta p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Footer */
.footer {
    background: #1a1a1a;
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    color: #ffd700;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #ffd700;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #333;
    color: #999;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hero-content h2 {
        font-size: 2.5rem;
    }
    
    .hero-content p {
        font-size: 1.1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .features-grid,
    .steps-container,
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    .floating-card,
    .btn,
    .feature-card,
    .step,
    .category-card {
        animation: none;
        transition: none;
    }
}

/* Focus styles for accessibility */
.btn:focus,
.nav-link:focus {
    outline: 3px solid #ffd700;
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .btn-primary {
        background: #000;
        color: #fff;
        border: 2px solid #fff;
    }
    
    .btn-secondary {
        background: #fff;
        color: #000;
        border: 2px solid #000;
    }
}