/* AI创新创业协会网站样式表 */

:root {
    --primary: #4a90e2;
    --secondary: #2c5282;
    --accent: #63b3ed;
    --dark: #2d3748;
    --light: #f7fafc;
    --gray: #718096;
    --success: #48bb78;
    --warning: #ed8936;
    --danger: #f56565;
    --comfort-bg: #f0f7ff;
    --comfort-card: #ffffff;
    --comfort-text: #2d3748;
    --comfort-subtle: #e2e8f0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.7;
    color: var(--comfort-text);
    background-color: var(--comfort-bg);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 导航栏样式 */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary);
    text-decoration: none;
}

.logo img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--primary);
    transition: transform 0.3s ease;
}

.logo:hover img {
    transform: rotate(360deg);
}

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

.nav-menu a {
    text-decoration: none;
    color: var(--dark);
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

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

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

/* 主页横幅 */
.hero {
    margin-top: 80px;
    min-height: 100vh;
    background: linear-gradient(135deg, #4a90e2 0%, #2c5282 50%, #1a365d 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(circle at 20% 30%, rgba(255,255,255,0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(255,255,255,0.05) 0%, transparent 50%),
        url('../images/pattern.svg') repeat;
    opacity: 0.4;
}

.hero::after {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, transparent 0%, rgba(0,0,0,0.2) 100%);
    opacity: 0.2;
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: 2rem;
    max-width: 800px;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    animation: fadeInUp 1s ease;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero .subtitle {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    animation: fadeInUp 1s ease 0.2s;
    animation-fill-mode: both;
}

.hero .description {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease 0.4s;
    animation-fill-mode: both;
    opacity: 0.9;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    animation: fadeInUp 1s ease 0.6s;
    animation-fill-mode: both;
}

.btn {
    padding: 0.8rem 2rem;
    border: none;
    border-radius: 50px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    font-weight: 600;
}

.btn-primary {
    background: white;
    color: var(--primary);
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

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

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
}

/* 内容区块 */
.section {
    padding: 5rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
    background: transparent;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--comfort-text);
    position: relative;
    font-weight: 600;
}

.section-title::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    margin: 1rem auto;
    border-radius: 2px;
    opacity: 0.8;
}

/* 社团介绍 */
.intro-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    background: rgba(255,255,255,0.6);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

.intro-text h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--primary);
    font-weight: 600;
}

.intro-text p {
    font-size: 1.1rem;
    color: var(--comfort-text);
    margin-bottom: 1rem;
    line-height: 1.8;
    opacity: 0.9;
}

.intro-image {
    width: 100%;
    height: 400px;
    background: linear-gradient(135deg, #63b3ed 0%, #4a90e2 50%, #2c5282 100%);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(74,144,226,0.2);
}

.intro-image::before {
    content: '🤖';
    font-size: 8rem;
    opacity: 0.25;
    filter: blur(1px);
}

/* 活动展示 */
.activities {
    background: linear-gradient(135deg, #f0f7ff, #e6f0ff);
    position: relative;
}

.activities::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 20px;
    background: linear-gradient(180deg, rgba(74,144,226,0.05) 0%, transparent 100%);
    pointer-events: none;
}

.activity-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.activity-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    position: relative;
}

.activity-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.15);
}

.activity-image {
    height: 200px;
    background: linear-gradient(135deg, var(--accent), var(--primary));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    position: relative;
    overflow: hidden;
}

.activity-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, transparent, rgba(255,255,255,0.3));
}

.activity-content {
    padding: 1.5rem;
}

.activity-content h3 {
    margin-bottom: 0.5rem;
    color: var(--dark);
    font-size: 1.3rem;
}

.activity-content p {
    color: var(--gray);
    line-height: 1.6;
}

/* 聊天入口 - 社团文化节特别活动 */
.chat-section {
    background: linear-gradient(135deg, #4a90e2 0%, #2c5282 50%, #1a365d 100%);
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.chat-section::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 0 100 100"><text x="10" y="20" font-size="12" fill="white" opacity="0.1">2026</text><text x="60" y="40" font-size="10" fill="white" opacity="0.1">社团文化节</text><text x="30" y="80" font-size="8" fill="white" opacity="0.1">线上答题</text></svg>') repeat;
    opacity: 0.3;
    pointer-events: none;
}

.chat-container {
    max-width: 900px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.chat-header {
    margin-bottom: 2rem;
}

.chat-header .event-date {
    background: rgba(255,255,255,0.2);
    padding: 0.5rem 1.5rem;
    border-radius: 20px;
    display: inline-block;
    margin-bottom: 1rem;
    font-weight: 600;
    font-size: 1.1rem;
}

.chat-box {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(12px);
    border-radius: 20px;
    padding: 3rem;
    margin-top: 2rem;
    border: 1px solid rgba(255,255,255,0.3);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.chat-box h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.chat-box p {
    font-size: 1.2rem;
    opacity: 0.95;
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.chat-box .highlight {
    background: rgba(255,255,255,0.2);
    padding: 0.5rem 1rem;
    border-radius: 10px;
    display: inline-block;
    margin: 0.5rem 0;
    font-weight: 600;
}

.chat-box .highlight.number {
    background: rgba(72, 187, 120, 0.3);
    font-size: 1.5rem;
    padding: 0.8rem 1.2rem;
}

/* 教程区域 */
.tutorial-section {
    background: var(--comfort-bg);
    padding: 4rem 2rem;
    position: relative;
}

.tutorial-container {
    max-width: 1000px;
    margin: 0 auto;
}

.tutorial-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.tutorial-card {
    background: var(--comfort-card);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
}

.tutorial-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.12);
}

.tutorial-image {
    width: 100%;
    height: 250px;
    object-fit: cover;
    border-bottom: 3px solid var(--primary);
}

.tutorial-content {
    padding: 1.5rem;
    text-align: center;
}

.tutorial-content h4 {
    color: var(--primary);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.tutorial-content p {
    color: var(--gray);
    font-size: 0.9rem;
    line-height: 1.5;
}

.tutorial-step {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
    position: absolute;
    top: -20px;
    left: 20px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.2);
}

.tutorial-card {
    position: relative;
}

/* 参与按钮 */
.participate-button {
    background: linear-gradient(135deg, #48bb78, #38a169);
    color: white;
    padding: 1.2rem 3rem;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    margin-top: 1.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(72, 187, 120, 0.4);
    position: relative;
    overflow: hidden;
}

.participate-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(72, 187, 120, 0.6);
}

.participate-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: 0.5s;
}

.participate-button:hover::before {
    left: 100%;
}

/* 活动统计 */
.event-stats {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.stat-item {
    background: rgba(255,255,255,0.1);
    padding: 1rem 1.5rem;
    border-radius: 10px;
    text-align: center;
}

.stat-item .number {
    font-size: 1.8rem;
    font-weight: bold;
    color: #48bb78;
    display: block;
}

.stat-item .label {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* 社团成就 */
.achievements {
    background: var(--comfort-bg);
    position: relative;
}

.achievements::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 20px;
    background: linear-gradient(180deg, rgba(74,144,226,0.03) 0%, transparent 100%);
    pointer-events: none;
}

.achievement-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.achievement-card {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

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

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

.achievement-card h3 {
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.achievement-card p {
    color: var(--gray);
}

/* 页脚 */
footer {
    background: linear-gradient(135deg, var(--dark), #0f172a);
    color: white;
    padding: 3rem 2rem;
    text-align: center;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-content h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.footer-content p {
    margin-bottom: 0.5rem;
    opacity: 0.8;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 1.5rem 0;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    transition: all 0.3s ease;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.1);
}

.social-links a:hover {
    color: var(--accent);
    background: rgba(255,255,255,0.2);
    transform: translateY(-3px);
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    /* 导航栏优化 */
    .nav-container {
        padding: 0.8rem 1rem;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        gap: 1rem;
    }

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

    .nav-menu a {
        padding: 0.8rem 1rem;
        border-radius: 8px;
        transition: background 0.3s ease;
    }

    .nav-menu a:hover {
        background: var(--light);
    }

    .menu-toggle {
        display: block !important;
        position: absolute;
        right: 1rem;
        top: 50%;
        transform: translateY(-50%);
        font-size: 1.5rem;
        cursor: pointer;
        color: var(--primary);
    }

    /* 主页横幅优化 */
    .hero {
        min-height: 80vh;
        padding: 2rem 1rem;
    }

    .hero h1 {
        font-size: 2.2rem;
        margin-bottom: 0.8rem;
    }

    .hero .subtitle {
        font-size: 1.1rem;
        margin-bottom: 0.8rem;
    }

    .hero .description {
        font-size: 1rem;
        margin-bottom: 1.5rem;
        padding: 0 1rem;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
        gap: 0.8rem;
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }

    .btn {
        width: 100%;
        padding: 0.9rem 1.5rem;
        font-size: 1rem;
        text-align: center;
    }

    /* 内容区块优化 */
    .section {
        padding: 2.5rem 1rem;
    }

    .section-title {
        font-size: 1.8rem;
        margin-bottom: 2rem;
    }

    .section-title::after {
        width: 60px;
        height: 3px;
    }

    /* 社团介绍优化 */
    .intro-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .intro-text h3 {
        font-size: 1.5rem;
        margin-bottom: 0.8rem;
    }

    .intro-text p {
        font-size: 1rem;
        line-height: 1.6;
    }

    .intro-image {
        height: 300px;
        font-size: 1.2rem;
    }

    .intro-image::before {
        font-size: 6rem;
    }

    /* 活动展示优化 */
    .activity-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .activity-card {
        border-radius: 12px;
    }

    .activity-image {
        height: 180px;
        font-size: 2.5rem;
    }

    .activity-content {
        padding: 1.2rem;
    }

    .activity-content h3 {
        font-size: 1.2rem;
        margin-bottom: 0.5rem;
    }

    .activity-content p {
        font-size: 0.9rem;
        line-height: 1.5;
    }

    /* 社团成就优化 */
    .achievement-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .achievement-card {
        padding: 1.5rem;
    }

    .achievement-icon {
        font-size: 2.5rem;
        margin-bottom: 0.8rem;
    }

    .achievement-card h3 {
        font-size: 1.2rem;
    }

    .achievement-card p {
        font-size: 0.9rem;
    }

    /* 聊天入口优化 */
    .chat-box {
        padding: 2rem 1.5rem;
        margin-top: 1.5rem;
    }

    .chat-box h3 {
        font-size: 1.5rem;
        margin-bottom: 0.8rem;
    }

    .chat-box p {
        font-size: 1rem;
        line-height: 1.5;
    }

    /* 教程优化 */
    .tutorial-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .tutorial-image {
        height: 200px;
    }

    .tutorial-content {
        padding: 1.2rem;
    }

    .tutorial-content h4 {
        font-size: 1rem;
    }

    .tutorial-content p {
        font-size: 0.85rem;
    }

    /* 参与按钮优化 */
    .participate-button {
        padding: 1rem 2rem;
        font-size: 1rem;
        width: 90%;
        max-width: 300px;
    }

    /* 统计优化 */
    .event-stats {
        gap: 1rem;
    }

    .stat-item {
        padding: 0.8rem 1.2rem;
        min-width: 120px;
    }

    .stat-item .number {
        font-size: 1.5rem;
    }

    .stat-item .label {
        font-size: 0.8rem;
    }

    /* 页脚优化 */
    .footer-content h3 {
        font-size: 1.5rem;
    }

    .footer-content p {
        font-size: 0.9rem;
        margin-bottom: 0.4rem;
    }

    .social-links {
        gap: 0.8rem;
        margin: 1.2rem 0;
    }

    .social-links a {
        width: 36px;
        height: 36px;
        font-size: 1.2rem;
    }

    /* 触摸优化 */
    * {
        -webkit-tap-highlight-color: transparent;
    }

    .btn, .nav-menu a, .activity-card, .achievement-card {
        cursor: pointer;
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        user-select: none;
    }
}

/* 超小屏幕优化 */
@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.8rem;
    }

    .hero .subtitle {
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .btn {
        padding: 0.8rem 1.2rem;
        font-size: 0.9rem;
    }

    .logo {
        font-size: 1.2rem;
    }

    .logo img {
        width: 35px;
        height: 35px;
    }
}

/* 横屏模式优化 */
@media (max-width: 768px) and (orientation: landscape) {
    .hero {
        min-height: 100vh;
        padding: 4rem 1rem 2rem;
    }

    .hero-content {
        padding: 1rem;
    }

    .intro-grid {
        gap: 1.5rem;
    }

    .section {
        padding: 2rem 1rem;
    }
}