/**
 * 垦荒学园AI导航 - 样式文件
 * 现代科技感设计风格
 */

/* CSS变量定义 */
:root {
    --primary: #6366f1;
    --primary-light: #818cf8;
    --primary-dark: #4f46e5;
    --secondary: #10b981;
    --accent: #f59e0b;
    --background: #0f172a;
    --surface: #1e293b;
    --surface-light: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border: #334155;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.3);
    --radius-sm: 0.375rem;
    --radius: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --transition: all 0.3s ease;
}

/* 重置和基础样式 */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

/* 容器 */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 1.5rem;
}

.logo-text {
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-link {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
    padding: 0.5rem 0;
}

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

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

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

/* 移动端导航切换按钮 */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* 主页横幅 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 0 4rem;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(ellipse at 20% 80%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(16, 185, 129, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 50%, rgba(245, 158, 11, 0.05) 0%, transparent 70%);
    z-index: -2;
}

.hero-particles {
    position: absolute;
    inset: 0;
    z-index: -1;
    overflow: hidden;
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: linear-gradient(135deg, #818cf8 0%, #6366f1 25%, #a855f7 50%, #ec4899 75%, #f43f5e 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 3s ease infinite;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% center; }
    50% { background-position: 100% center; }
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 2.5rem;
    line-height: 1.8;
}

/* 搜索框 */
.hero-search {
    max-width: 600px;
    margin: 0 auto 3rem;
}

.search-box {
    position: relative;
    display: flex;
    align-items: center;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    padding: 0.5rem;
    transition: var(--transition);
}

.search-box:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.search-box.small {
    max-width: 400px;
}

.search-icon {
    width: 20px;
    height: 20px;
    color: var(--text-muted);
    margin: 0 0.75rem;
    flex-shrink: 0;
}

.search-box input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-size: 0.9375rem;
    padding: 0.5rem 0;
}

.search-box input::placeholder {
    color: var(--text-muted);
}

.search-btn {
    background: var(--primary);
    color: white;
    padding: 0.625rem 1.5rem;
    border-radius: var(--radius-lg);
    font-weight: 500;
    transition: var(--transition);
}

.search-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

/* 统计数据 */
.hero-stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* 通用区块样式 */
.section {
    padding: 5rem 0;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-badge {
    display: inline-block;
    padding: 0.375rem 1rem;
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-light);
    margin-bottom: 1rem;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.section-desc {
    font-size: 1rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

/* 分类标签 */
.category-tabs {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: 2rem;
}

.tab-btn {
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-lg);
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-secondary);
    background: transparent;
    border: 1px solid transparent;
    transition: var(--transition);
}

.tab-btn:hover {
    color: var(--text-primary);
    background: var(--surface);
}

.tab-btn.active {
    color: var(--primary-light);
    background: rgba(99, 102, 241, 0.1);
    border-color: rgba(99, 102, 241, 0.3);
}

/* 工具筛选 */
.tools-filter {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 2rem;
    padding: 1rem;
    background: var(--surface);
    border-radius: var(--radius-lg);
}

.filter-options {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
}

.checkbox-label:hover {
    color: var(--text-primary);
}

.checkbox-label input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    accent-color: var(--primary);
    cursor: pointer;
}

/* 工具网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

/* 工具卡片 */
.tool-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.tool-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--secondary), var(--accent));
    opacity: 0;
    transition: var(--transition);
}

.tool-card:hover {
    transform: translateY(-4px);
    border-color: var(--primary);
    box-shadow: var(--shadow-glow);
}

.tool-card:hover::before {
    opacity: 1;
}

.tool-card.hidden {
    display: none;
}

/* 卡片头部 */
.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.tool-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
}

.favorite-btn {
    width: 36px;
    height: 36px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    color: var(--text-muted);
    background: var(--surface-light);
    transition: var(--transition);
}

.favorite-btn:hover {
    background: rgba(245, 158, 11, 0.2);
    color: var(--accent);
}

.favorite-btn.active {
    background: rgba(245, 158, 11, 0.2);
    color: var(--accent);
}

/* 卡片内容 */
.tool-name {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.tool-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* 标签 */
.tool-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.625rem;
    border-radius: var(--radius);
    background: var(--surface-light);
    color: var(--text-secondary);
    font-weight: 500;
}

/* 卡片底部 */
.card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.tool-meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.rating {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    color: var(--accent);
}

.free-badge {
    font-size: 0.75rem;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius);
    background: rgba(16, 185, 129, 0.2);
    color: var(--secondary);
    font-weight: 500;
}

.visit-btn {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-light);
    display: flex;
    align-items: center;
    gap: 0.25rem;
    transition: var(--transition);
}

.visit-btn:hover {
    color: var(--primary);
    gap: 0.5rem;
}

/* 资讯区块 */
.news-section {
    background: linear-gradient(180deg, var(--background) 0%, rgba(99, 102, 241, 0.03) 50%, var(--background) 100%);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 1.5rem;
}

.news-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    transition: var(--transition);
    cursor: pointer;
}

.news-card:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.news-category {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 500;
    padding: 0.25rem 0.625rem;
    border-radius: var(--radius);
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-light);
    margin-bottom: 0.75rem;
}

.news-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-summary {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8125rem;
    color: var(--text-muted);
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

/* 收藏区块 */
.favorites-section {
    background: linear-gradient(180deg, var(--background) 0%, rgba(245, 158, 11, 0.02) 50%, var(--background) 100%);
}

.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    background: var(--surface);
    border: 2px dashed var(--border);
    border-radius: var(--radius-xl);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.empty-state h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.empty-state p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

.btn-outline {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    background: var(--surface);
    color: var(--text-primary);
    border-color: var(--primary);
}

/* 加载更多 */
.load-more {
    text-align: center;
    margin-top: 3rem;
}

/* 页脚 */
.footer {
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer-brand .logo {
    margin-bottom: 1rem;
}

.footer-desc {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    line-height: 1.6;
    max-width: 300px;
}

.footer-column h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

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

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

.footer-column a {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    transition: var(--transition);
}

.footer-column a:hover {
    color: var(--primary-light);
}

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.footer-note {
    margin-top: 0.5rem;
}

/* 弹窗 */
.modal {
    position: fixed;
    inset: 0;
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.modal.active {
    opacity: 1;
    visibility: visible;
}

.modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: var(--transition);
}

.modal.active .modal-content {
    transform: scale(1);
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--text-secondary);
    background: var(--surface-light);
    border-radius: var(--radius);
    transition: var(--transition);
    z-index: 10;
}

.modal-close:hover {
    color: var(--text-primary);
    background: var(--border);
}

.modal-body {
    padding: 2rem;
}

/* 回到顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 100;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.back-to-top svg {
    width: 20px;
    height: 20px;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: 2rem;
    }
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 4rem;
        left: 0;
        right: 0;
        background: var(--surface);
        border-bottom: 1px solid var(--border);
        flex-direction: column;
        padding: 1rem;
        gap: 0;
        opacity: 0;
        visibility: hidden;
        transform: translateY(-10px);
        transition: var(--transition);
    }

    .nav-menu.active {
        opacity: 1;
        visibility: visible;
        transform: translateY(0);
    }

    .nav-menu li {
        width: 100%;
    }

    .nav-link {
        display: block;
        padding: 0.75rem 1rem;
        border-radius: var(--radius);
    }

    .nav-link:hover,
    .nav-link.active {
        background: var(--surface-light);
    }

    .nav-link::after {
        display: none;
    }

    .hero-stats {
        gap: 2rem;
    }

    .stat-number {
        font-size: 2rem;
    }

    .tools-filter {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-options {
        justify-content: center;
    }

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

    .footer-desc {
        max-width: none;
    }

    .modal-content {
        width: 95%;
        margin: 1rem;
    }

    .modal-body {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .section {
        padding: 3rem 0;
    }

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

    .tools-grid,
    .news-grid {
        grid-template-columns: 1fr;
    }

    .category-tabs {
        gap: 0.375rem;
    }

    .tab-btn {
        padding: 0.5rem 1rem;
        font-size: 0.875rem;
    }
}

/* 隐藏元素 */
.hidden {
    display: none !important;
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.5s ease forwards;
}

/* 粒子背景 */
.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: rgba(99, 102, 241, 0.5);
    border-radius: 50%;
    pointer-events: none;
    animation: float 15s infinite linear;
}

@keyframes float {
    0% {
        transform: translateY(100vh) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(-100px) rotate(720deg);
        opacity: 0;
    }
}