:root {
    --primary-color: #2b90d9;
    --secondary-color: #282c37;
    --background-dark: #1f232b;
    --background-color: #ffffff;
    --text-color: #333333;
    --light-gray: #f5f5f5;
    --border-color: #e6e6e6;
    --success-color: #79bd9a;
    --error-color: #df405a;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

/* Header Styles */
.main-header {
    background-color: var(--background-dark);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    color: white;
    font-size: 1.8rem;
    font-weight: bold;
}

.nav-links a {
    color: white;
    text-decoration: none;
    margin: 0 1rem;
    padding: 0.5rem;
    transition: color 0.3s ease;
    opacity: 0.8;
}

.nav-links a:hover {
    color: white;
    opacity: 1;
}

.nav-links a.active {
    color: white;
    opacity: 1;
    font-weight: 600;
}

/* 导航栏按钮样式 */
.auth-buttons {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.btn-login {
    color: white !important;
    padding: 0.5rem 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: 9999px;
    transition: all 0.3s ease;
}

.btn-login:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: white;
}

.btn-register {
    color: white !important;
    background-color: var(--primary-color);
    padding: 0.5rem 1.5rem;
    border-radius: 9999px;
    border: none;
    transition: all 0.3s ease;
}

.btn-register:hover {
    background-color: #3aa0e9;
    transform: translateY(-2px);
}

/* 确保暗色模式下按钮颜色正确 */
@media (prefers-color-scheme: dark) {
    .btn-login {
        color: white !important;
        border-color: rgba(255, 255, 255, 0.5);
    }

    .btn-register {
        color: white !important;
        background-color: var(--primary-color);
    }
}

/* Hero Section */
.hero {
    position: relative;
    padding: 8rem 2rem 4rem;
    background: url('../images/openart-image_IaxO1fVg_1736596495779_raw.png') no-repeat center center;
    background-size: cover;
    background-attachment: fixed;
    color: white;
    overflow: hidden;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(31, 35, 43, 0.75);
    z-index: 1;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 100px;
    background: white;
    clip-path: polygon(0 100%, 100% 100%, 100% 0, 0 100%);
    z-index: 1;
}

.hero-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
}

.hero-content {
    flex: 1;
    max-width: 600px;
    text-align: left;
    padding-right: 2rem;
}

.hero h1 {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero p {
    font-size: clamp(1rem, 2vw, 1.4rem);
    margin-bottom: 2rem;
    opacity: 0.9;
    max-width: 540px;
}

.hero-illustration {
    flex: 1;
    max-width: 500px;
    position: relative;
    aspect-ratio: 1/1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-illustration img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    object-position: center;
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 9999px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    border: none;
}

.btn-secondary {
    background-color: white;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* Features Section */
.features {
    padding: 6rem 2rem;
    background-color: white;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    transition: transform 0.3s ease;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

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

.feature-card i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

/* Footer Styles */
.main-footer {
    background-color: var(--background-dark);
    color: white;
    padding: 4rem 2rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
}

.footer-section h4 {
    margin-bottom: 1.5rem;
    font-size: 1.2rem;
    color: white;
}

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

.footer-section ul li {
    margin-bottom: 0.8rem;
}

.footer-section a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.footer-section a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    margin-top: 4rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.8);
}

/* Decorative Elements */
.floating-circles {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
    z-index: 1;
}

.circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
}

.circle-1 {
    width: 100px;
    height: 100px;
    top: 10%;
    right: 10%;
}

.circle-2 {
    width: 150px;
    height: 150px;
    bottom: 20%;
    left: 5%;
}

/* Responsive Design */
@media screen and (max-width: 1024px) {
    .hero-container {
        flex-direction: column;
        text-align: center;
        padding-top: 2rem;
    }

    .hero-content {
        padding-right: 0;
        text-align: center;
        margin-bottom: 3rem;
    }

    .hero-illustration {
        max-width: 400px;
        margin: 0 auto;
    }
}

@media screen and (max-width: 768px) {
    .hero {
        padding: 6rem 1rem 3rem;
        min-height: auto;
    }

    .hero-illustration {
        max-width: 300px;
    }

    .cta-buttons {
        display: flex;
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 300px;
        text-align: center;
    }
}