/* 燕雪AI官网样式表 */

/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #4FC3F7;
    --primary-dark: #0D47A1;
    --secondary: #81D4FA;
    --background: #FAFAFA;
    --surface: #FFFFFF;
    --text: #212121;
    --text-light: #757575;
    --border: #E0E0E0;
    --shadow: rgba(0, 0, 0, 0.1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
    background-color: var(--background);
    color: var(--text);
    line-height: 1.6;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px var(--shadow);
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text);
    font-size: 1.5rem;
    font-weight: 700;
}

.logo-icon {
    font-size: 2rem;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s;
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text);
    border-radius: 3px;
    transition: 0.3s;
}

/* Hero 区域 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background: linear-gradient(135deg, #E3F2FD 0%, #BBDEFB 50%, #90CAF9 100%);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
}

.snowflake {
    position: absolute;
    color: rgba(255, 255, 255, 0.6);
    font-size: 2rem;
    animation: fall linear infinite;
}

.snowflake:nth-child(1) { left: 10%; animation-duration: 10s; animation-delay: 0s; }
.snowflake:nth-child(2) { left: 30%; animation-duration: 12s; animation-delay: 2s; }
.snowflake:nth-child(3) { left: 50%; animation-duration: 8s; animation-delay: 4s; }
.snowflake:nth-child(4) { left: 70%; animation-duration: 11s; animation-delay: 1s; }
.snowflake:nth-child(5) { left: 90%; animation-duration: 9s; animation-delay: 3s; }

@keyframes fall {
    0% { transform: translateY(-100vh) rotate(0deg); opacity: 1; }
    100% { transform: translateY(100vh) rotate(360deg); opacity: 0.3; }
}

.hero-content {
    text-align: center;
    z-index: 1;
    padding: 20px;
}

.avatar-container {
    margin-bottom: 30px;
}

.avatar {
    width: 150px;
    height: 150px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    margin: 0 auto;
    box-shadow: 0 10px 40px rgba(79, 195, 247, 0.4);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); box-shadow: 0 10px 40px rgba(79, 195, 247, 0.4); }
    50% { transform: scale(1.05); box-shadow: 0 15px 50px rgba(79, 195, 247, 0.6); }
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 10px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 15px;
    font-weight: 500;
}

.hero-tagline {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 40px;
}

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

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 15px 35px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    box-shadow: 0 5px 20px rgba(79, 195, 247, 0.4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(79, 195, 247, 0.5);
}

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

.btn-secondary:hover {
    background: var(--primary);
    color: white;
}

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

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

/* 服务区域 */
.services {
    padding: 100px 0;
    background: var(--surface);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    color: var(--primary-dark);
    margin-bottom: 15px;
}

.section-desc {
    text-align: center;
    color: var(--text-light);
    margin-bottom: 50px;
    font-size: 1.1rem;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.service-card {
    background: var(--background);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: all 0.3s;
    border: 1px solid var(--border);
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px var(--shadow);
    border-color: var(--primary);
}

.service-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.service-card h3 {
    font-size: 1.3rem;
    color: var(--primary-dark);
    margin-bottom: 15px;
}

.service-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* 能力区域 */
.capabilities {
    padding: 100px 0;
    background: linear-gradient(135deg, #E3F2FD 0%, #FAFAFA 100%);
}

.capabilities-list {
    display: flex;
    flex-direction: column;
    gap: 30px;
    max-width: 800px;
    margin: 0 auto;
}

.capability-item {
    display: flex;
    align-items: flex-start;
    gap: 25px;
    background: var(--surface);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 5px 20px var(--shadow);
    transition: all 0.3s;
}

.capability-item:hover {
    transform: translateX(10px);
    box-shadow: 0 10px 30px var(--shadow);
}

.capability-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
}

.capability-content h3 {
    font-size: 1.3rem;
    color: var(--primary-dark);
    margin-bottom: 10px;
}

.capability-content p {
    color: var(--text-light);
}

/* 关于预览区域 */
.about-preview {
    padding: 100px 0;
    background: var(--surface);
}

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

.about-text h2 {
    font-size: 2.5rem;
    color: var(--primary-dark);
    margin-bottom: 25px;
}

.about-text p {
    color: var(--text-light);
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.8;
}

.about-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.snowflake-large {
    font-size: 15rem;
    animation: float 4s ease-in-out infinite;
    filter: drop-shadow(0 20px 40px rgba(79, 195, 247, 0.3));
}

/* 页脚 */
.footer {
    background: var(--primary-dark);
    color: white;
    padding: 60px 0 30px;
}

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

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.footer-tagline {
    color: var(--secondary);
    margin-bottom: 30px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

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

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

.footer-copyright {
    color: var(--secondary);
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        gap: 15px;
        box-shadow: 0 10px 20px var(--shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

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

    .hero-subtitle {
        font-size: 1.2rem;
    }

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

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .about-visual {
        order: -1;
    }

    .snowflake-large {
        font-size: 8rem;
    }

    .capability-item {
        flex-direction: column;
        text-align: center;
    }

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

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .avatar {
        width: 120px;
        height: 120px;
        font-size: 3rem;
    }

    .btn {
        padding: 12px 25px;
        font-size: 0.9rem;
    }
}