/* ========================================
   需求库平台 - 科技感主题样式
   ======================================== */

/* CSS变量定义 */
:root {
    /* 主色调 */
    --primary-color: #00d4ff;
    --primary-dark: #00a8cc;
    --primary-light: #4de8ff;
    --secondary-color: #7c3aed;
    --accent-color: #00ff88;
    
    /* 背景色 */
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a25;
    --bg-card: rgba(26, 26, 37, 0.8);
    --bg-card-hover: rgba(38, 38, 55, 0.9);
    
    /* 文字色 */
    --text-primary: #ffffff;
    --text-secondary: #a0a0b0;
    --text-muted: #666680;
    
    /* 边框 */
    --border-color: rgba(0, 212, 255, 0.2);
    --border-glow: rgba(0, 212, 255, 0.5);
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #7c3aed 100%);
    --gradient-secondary: linear-gradient(135deg, #7c3aed 0%, #00ff88 100%);
    --gradient-dark: linear-gradient(180deg, #0a0a0f 0%, #12121a 100%);
    
    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(0, 212, 255, 0.3);
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 9999px;
    
    /* 字体 */
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* 过渡 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* 重置样式 */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-light);
}

/* 选中文本 */
::selection {
    background: var(--primary-color);
    color: var(--bg-primary);
}

/* 链接样式 */
a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

/* ========================================
   粒子背景容器
   ======================================== */
#particles-js {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
}

/* 动态网格背景 */
.grid-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(rgba(0, 212, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 212, 255, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    z-index: -2;
    pointer-events: none;
}

/* ========================================
   导航栏
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 70px;
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    display: flex;
    align-items: center;
    padding: 0 40px;
    transition: all var(--transition-normal);
}

.navbar.scrolled {
    background: rgba(10, 10, 15, 0.95);
    box-shadow: var(--shadow-md);
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
}

.navbar-brand .logo-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

.navbar-nav {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: auto;
    margin-right: 40px;
}

.nav-link {
    padding: 10px 20px;
    color: var(--text-secondary);
    font-weight: 500;
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
    background: rgba(0, 212, 255, 0.1);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 30px;
    height: 3px;
    background: var(--primary-color);
    border-radius: var(--radius-full);
}

.navbar-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    font-size: 14px;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s ease;
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--text-primary);
    box-shadow: 0 4px 15px rgba(0, 212, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(0, 212, 255, 0.5);
}

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

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

.btn-ghost {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--primary-color);
}

.btn-sm {
    padding: 8px 16px;
    font-size: 12px;
}

.btn-lg {
    padding: 16px 36px;
    font-size: 16px;
}

.btn-icon {
    width: 44px;
    height: 44px;
    padding: 0;
    border-radius: 50%;
}

/* ========================================
   搜索框
   ======================================== */
.search-box {
    position: relative;
    width: 100%;
    max-width: 600px;
}

.search-input {
    width: 100%;
    padding: 16px 24px;
    padding-right: 120px;
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-full);
    color: var(--text-primary);
    font-size: 16px;
    transition: all var(--transition-fast);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: var(--shadow-glow);
}

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

.search-btn {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    padding: 10px 24px;
}

.search-suggestions {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin-top: 8px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    display: none;
    z-index: 100;
}

.search-suggestions.show {
    display: block;
    animation: fadeInDown 0.2s ease;
}

.search-suggestion-item {
    padding: 12px 20px;
    cursor: pointer;
    transition: background var(--transition-fast);
}

.search-suggestion-item:hover {
    background: rgba(0, 212, 255, 0.1);
}

/* ========================================
   卡片样式
   ======================================== */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 24px;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.card:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary-color);
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
}

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

/* 需求卡片 */
.demand-card {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.demand-card .card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 16px;
}

.demand-card .card-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.demand-card .card-title:hover {
    color: var(--primary-color);
}

.demand-card .card-badge {
    flex-shrink: 0;
    padding: 4px 12px;
    background: rgba(0, 212, 255, 0.15);
    color: var(--primary-color);
    font-size: 12px;
    font-weight: 500;
    border-radius: var(--radius-full);
    white-space: nowrap;
}

.demand-card .card-body {
    flex: 1;
}

.demand-card .card-desc {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.6;
    margin-bottom: 16px;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.demand-card .card-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 16px;
}

.demand-card .meta-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-muted);
    font-size: 13px;
}

.demand-card .meta-item i {
    color: var(--primary-color);
}

.demand-card .card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
}

.demand-card .card-budget {
    font-size: 20px;
    font-weight: 700;
    color: var(--accent-color);
}

.demand-card .card-budget small {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 400;
}

/* ========================================
   首页Hero区域
   ======================================== */
.hero {
    min-height: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 140px 40px 60px;
    position: relative;
    overflow: hidden;
}

.hero-content {
    text-align: center;
    max-width: 1200px;
    width: 100%;
    z-index: 1;
}

.hero-title {
    font-size: 64px;
    font-weight: 800;
    margin-bottom: 24px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-search {
    display: flex;
    justify-content: center;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin-top: 80px;
    animation: fadeInUp 0.8s ease 0.6s both;
}

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

.stat-value {
    font-size: 48px;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
}

.stat-value .counter {
    min-width: 80px;
}

.stat-value span {
    font-size: 20px;
    color: var(--text-muted);
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 8px;
}

/* ========================================
   行业分类导航
   ======================================== */
.category-nav {
    padding: 80px 40px;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-desc {
    color: var(--text-secondary);
    font-size: 16px;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 20px;
    max-width: 1200px;
    margin: 0 auto;
}

/* 首页统一容器宽度 */
.home-container {
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.category-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 30px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.category-item:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary-color);
    transform: translateY(-8px);
    box-shadow: var(--shadow-glow);
}

.category-icon {
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: 50%;
    font-size: 24px;
    margin-bottom: 16px;
    transition: transform var(--transition-normal);
}

.category-item:hover .category-icon {
    transform: scale(1.1) rotate(10deg);
}

.category-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.category-count {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* ========================================
   精选需求区域
   ======================================== */
.featured-section {
    padding: 80px 40px;
}

.demand-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
}

/* ========================================
   用户头像下拉菜单
   ======================================== */
.user-dropdown {
    position: relative;
}

.user-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 2px solid var(--primary-color);
    cursor: pointer;
    transition: all var(--transition-fast);
    object-fit: cover;
}

.user-avatar:hover {
    box-shadow: 0 0 15px var(--primary-color);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 10px;
    min-width: 200px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--transition-fast);
    z-index: 1000;
}

.user-dropdown:hover .dropdown-menu,
.dropdown-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-header {
    padding: 16px;
    background: rgba(0, 212, 255, 0.05);
    border-bottom: 1px solid var(--border-color);
}

.dropdown-header .username {
    font-weight: 600;
    color: var(--text-primary);
}

.dropdown-header .user-level {
    font-size: 12px;
    color: var(--primary-color);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.dropdown-item:hover {
    background: rgba(0, 212, 255, 0.1);
    color: var(--text-primary);
}

.dropdown-item i {
    width: 20px;
    text-align: center;
}

.dropdown-divider {
    height: 1px;
    background: var(--border-color);
    margin: 8px 0;
}

/* ========================================
   表单样式
   ======================================== */
.form-group {
    margin-bottom: 24px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-primary);
}

.form-label .required {
    color: #ff4757;
}

.form-control {
    width: 100%;
    padding: 14px 18px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 15px;
    transition: all var(--transition-fast);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.1);
}

.form-control::placeholder {
    color: var(--text-muted);
}

.form-control.is-invalid {
    border-color: #ff4757;
}

.invalid-feedback {
    color: #ff4757;
    font-size: 13px;
    margin-top: 6px;
}

textarea.form-control {
    min-height: 120px;
    resize: vertical;
}

.form-select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2300d4ff' stroke-width='2'%3E%3Cpolyline points='6,9 12,15 18,9'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
    padding-right: 48px;
}

/* ========================================
   标签/徽章
   ======================================== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    font-size: 12px;
    font-weight: 600;
    border-radius: var(--radius-full);
}

.badge-primary {
    background: rgba(0, 212, 255, 0.15);
    color: var(--primary-color);
}

.badge-success {
    background: rgba(0, 255, 136, 0.15);
    color: var(--accent-color);
}

.badge-warning {
    background: rgba(255, 193, 7, 0.15);
    color: #ffc107;
}

.badge-danger {
    background: rgba(255, 71, 87, 0.15);
    color: #ff4757;
}

.badge-secondary {
    background: rgba(160, 160, 176, 0.15);
    color: var(--text-secondary);
}

.badge-info {
    background: rgba(124, 58, 237, 0.15);
    color: var(--secondary-color);
}

/* ========================================
   加载动画
   ======================================== */
.loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.loading-text {
    margin-left: 16px;
    color: var(--text-secondary);
}

/* 粒子加载效果 */
.loading-particles {
    display: flex;
    gap: 8px;
}

.loading-particles span {
    width: 10px;
    height: 10px;
    background: var(--primary-color);
    border-radius: 50%;
    animation: bounce 0.6s infinite alternate;
}

.loading-particles span:nth-child(2) { animation-delay: 0.2s; }
.loading-particles span:nth-child(3) { animation-delay: 0.4s; }

/* ========================================
   返回顶部按钮
   ======================================== */
.back-to-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: white;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: 999;
    box-shadow: var(--shadow-glow);
}

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

.back-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 30px var(--primary-color);
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 60px 40px 30px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
}

.footer-brand {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.footer-desc {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.8;
}

.footer-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 20px;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 14px;
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    max-width: 1200px;
    margin: 40px auto 0;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: 14px;
}

/* ========================================
   分页
   ======================================== */
.pagination {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 40px;
}

.page-item {
    list-style: none;
}

.page-link {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    height: 44px;
    padding: 0 16px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-weight: 500;
    transition: all var(--transition-fast);
}

.page-link:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.page-item.active .page-link {
    background: var(--gradient-primary);
    border-color: transparent;
    color: white;
}

.page-item.disabled .page-link {
    opacity: 0.5;
    pointer-events: none;
}

/* ========================================
   模态框
   ======================================== */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9) translateY(20px);
    transition: transform var(--transition-normal);
}

.modal-overlay.show .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
}

.modal-title {
    font-size: 20px;
    font-weight: 600;
}

.modal-close {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 20px;
    cursor: pointer;
    border-radius: 50%;
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 12px;
    padding: 16px 24px;
    border-top: 1px solid var(--border-color);
}

/* ========================================
   消息提示
   ======================================== */
.toast-container {
    position: fixed;
    top: 90px;
    right: 20px;
    z-index: 3000;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    animation: slideInRight 0.3s ease;
    min-width: 300px;
}

.toast-success { border-left: 4px solid var(--accent-color); }
.toast-error { border-left: 4px solid #ff4757; }
.toast-warning { border-left: 4px solid #ffc107; }
.toast-info { border-left: 4px solid var(--primary-color); }

.toast-icon {
    font-size: 20px;
}

.toast-success .toast-icon { color: var(--accent-color); }
.toast-error .toast-icon { color: #ff4757; }
.toast-warning .toast-icon { color: #ffc107; }
.toast-info .toast-icon { color: var(--primary-color); }

.toast-message {
    flex: 1;
    font-size: 14px;
}

.toast-close {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 4px;
}

/* ========================================
   动画关键帧
   ======================================== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes bounce {
    to { transform: translateY(-10px); }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

@keyframes glow {
    0%, 100% { box-shadow: 0 0 5px var(--primary-color); }
    50% { box-shadow: 0 0 20px var(--primary-color), 0 0 40px var(--primary-color); }
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1200px) {
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 992px) {
    .hero-title {
        font-size: 48px;
    }
    
    .hero-stats {
        gap: 40px;
    }
    
    .stat-value {
        font-size: 36px;
    }
    
    .demand-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    .navbar {
        padding: 0 20px;
    }
    
    .navbar-nav {
        display: none;
    }
    
    .hero {
        padding: 100px 20px 60px;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-subtitle {
        font-size: 16px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 30px;
    }
    
    .category-nav,
    .featured-section {
        padding: 60px 20px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .category-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    }
    
    .demand-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .back-to-top {
        bottom: 20px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 28px;
    }
    
    .search-input {
        padding: 12px 16px;
        padding-right: 100px;
        font-size: 14px;
    }
    
    .search-btn {
        padding: 8px 16px;
        font-size: 12px;
    }
    
    .card {
        padding: 16px;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 13px;
    }
}

/* ========================================
   工具类
   ======================================== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--primary-color); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--accent-color); }
.text-danger { color: #ff4757; }

.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }
.mt-5 { margin-top: 48px; }

.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }
.mb-5 { margin-bottom: 48px; }

.p-1 { padding: 8px; }
.p-2 { padding: 16px; }
.p-3 { padding: 24px; }
.p-4 { padding: 32px; }

.d-flex { display: flex; }
.d-block { display: block; }
.d-none { display: none; }

.flex-wrap { flex-wrap: wrap; }
.align-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 8px; }
.gap-2 { gap: 16px; }
.gap-3 { gap: 24px; }

.w-100 { width: 100%; }
.h-100 { height: 100%; }

.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}