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

/* 根元素变量 */
:root {
    --primary-color: #1677ff;
    --secondary-color: #0366d6;
    --success-color: #52c41a;
    --warning-color: #faad14;
    --danger-color: #f5222d;
    --info-color: #1890ff;
    --dark-color: #1f2937;
    --gray-color: #6b7280;
    --light-gray-color: #f3f4f6;
    --white-color: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --border-radius: 0.5rem;
    --transition-speed: 0.3s;
    --font-family: 'Inter', 'system-ui', 'sans-serif';
}

/* 基础样式 */
body {
    font-family: var(--font-family);
    color: var(--dark-color);
    background-color: var(--light-gray-color);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 排版 */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.25;
    margin-bottom: 1rem;
}

h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
}

h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
}

h3 {
    font-size: clamp(1.5rem, 3vw, 2rem);
}

p {
    margin-bottom: 1rem;
}

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

a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: all var(--transition-speed) ease;
    cursor: pointer;
    border: none;
    outline: none;
    font-size: 1rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white-color);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-primary:focus:not(:active) {
    animation: ripple 1s ease-out;
}

.btn-secondary {
    background-color: var(--white-color);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

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

/* 卡片样式 */
.card {
    background-color: var(--white-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    padding: 1.5rem;
    transition: all var(--transition-speed) ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

/* 导航栏样式 */
.navbar {
    background-color: var(--white-color);
    box-shadow: var(--shadow-sm);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: all var(--transition-speed) ease;
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
}

/* 容器样式 */
.container {
    width: 100%;
    max-width: 7xl;
    margin: 0 auto;
    padding: 0 1rem;
}

@media (min-width: 640px) {
    .container {
        padding: 0 1.5rem;
    }
}

@media (min-width: 1024px) {
    .container {
        padding: 0 2rem;
    }
}

/* 部分间距 */
.section {
    padding: 6rem 0;
}

@media (max-width: 768px) {
    .section {
        padding: 4rem 0;
    }
}

/* 网格布局 */
.grid {
    display: grid;
    gap: 2rem;
}

.grid-cols-1 {
    grid-template-columns: repeat(1, minmax(0, 1fr));
}

@media (min-width: 640px) {
    .grid-cols-2 {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 1024px) {
    .grid-cols-3 {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    
    .grid-cols-4 {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

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

.mb-1 {
    margin-bottom: 0.25rem;
}

.mb-2 {
    margin-bottom: 0.5rem;
}

.mb-4 {
    margin-bottom: 1rem;
}

.mb-6 {
    margin-bottom: 1.5rem;
}

.mb-8 {
    margin-bottom: 2rem;
}

.mb-12 {
    margin-bottom: 3rem;
}

.mt-1 {
    margin-top: 0.25rem;
}

.mt-2 {
    margin-top: 0.5rem;
}

.mt-4 {
    margin-top: 1rem;
}

.mt-6 {
    margin-top: 1.5rem;
}

.mt-8 {
    margin-top: 2rem;
}

.mt-12 {
    margin-top: 3rem;
}

/* 背景颜色 */
.bg-white {
    background-color: var(--white-color);
}

.bg-gray {
    background-color: var(--light-gray-color);
}

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

.bg-gradient-blue {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.bg-gradient-indigo {
    background: linear-gradient(to right, #667eea 0%, #764ba2 100%);
}

/* 文本颜色 */
.text-primary {
    color: var(--primary-color);
}

.text-secondary {
    color: var(--secondary-color);
}

.text-success {
    color: var(--success-color);
}

.text-warning {
    color: var(--warning-color);
}

.text-danger {
    color: var(--danger-color);
}

.text-info {
    color: var(--info-color);
}

.text-gray {
    color: var(--gray-color);
}

.text-dark {
    color: var(--dark-color);
}

.text-white {
    color: var(--white-color);
}

/* 阴影效果 */
.shadow-sm {
    box-shadow: var(--shadow-sm);
}

.shadow-md {
    box-shadow: var(--shadow-md);
}

.shadow-lg {
    box-shadow: var(--shadow-lg);
}

.shadow-xl {
    box-shadow: var(--shadow-xl);
}

/* 圆角 */
.rounded {
    border-radius: var(--border-radius);
}

.rounded-full {
    border-radius: 9999px;
}

/* 过渡效果 */
.transition {
    transition: all var(--transition-speed) ease;
}

.transition-colors {
    transition: color var(--transition-speed) ease, background-color var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

.transition-transform {
    transition: transform var(--transition-speed) ease;
}

/* 变换效果 */
.hover-lift {
    transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
}

.hover-lift:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

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

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

@keyframes ripple {
    0% {
        transform: scale(0, 0);
        opacity: 0.5;
    }
    20% {
        transform: scale(25, 25);
        opacity: 0.5;
    }
    100% {
        opacity: 0;
        transform: scale(40, 40);
    }
}

.fade-in {
    animation: fadeIn 0.8s ease forwards;
}

.pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

.spin {
    animation: spin 1s linear infinite;
}

/* 响应式隐藏 */
.hidden {
    display: none;
}

@media (min-width: 768px) {
    .md\:hidden {
        display: none;
    }
    
    .md\:block {
        display: block;
    }
}

/* 移动端菜单 */
.mobile-menu {
    position: fixed;
    top: 4rem;
    left: 0;
    right: 0;
    background-color: var(--white-color);
    box-shadow: var(--shadow-md);
    padding: 1rem;
    z-index: 999;
    transform: translateY(-100%);
    transition: transform var(--transition-speed) ease;
}

.mobile-menu.open {
    transform: translateY(0);
}

/* 页脚样式 */
.footer {
    background-color: var(--dark-color);
    color: var(--white-color);
    padding: 3rem 0 1.5rem;
}

.footer-link {
    color: rgba(255, 255, 255, 0.7);
    transition: color var(--transition-speed) ease;
}

.footer-link:hover {
    color: var(--white-color);
}

/* FAQ 样式 */
.faq-item {
    border: 1px solid #e5e7eb;
    border-radius: var(--border-radius);
    overflow: hidden;
    margin-bottom: 1rem;
}

.faq-toggle {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    text-align: left;
    font-weight: 500;
    background-color: #f9fafb;
    border: none;
    cursor: pointer;
    transition: background-color var(--transition-speed) ease;
}

.faq-toggle:hover {
    background-color: #f3f4f6;
}

.faq-content {
    padding: 0 1rem 1rem;
    background-color: var(--white-color);
    display: none;
}

.faq-content.show {
    display: block;
}

.faq-toggle i {
    transition: transform var(--transition-speed) ease;
}

.faq-toggle.active i {
    transform: rotate(180deg);
}

/* 下载卡片样式 */
.download-card {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    border-radius: 1rem;
    overflow: hidden;
    transition: all 0.3s ease;
}

.download-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

/* 下载按钮样式 */
.download-btn {
    position: relative;
    overflow: hidden;
}

.download-btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 5px;
    height: 5px;
    background: rgba(255, 255, 255, 0.5);
    opacity: 0;
    border-radius: 100%;
    transform: scale(1, 1) translate(-50%, -50%);
    transform-origin: 50% 50%;
}

/* 平台图标 */
.platform-icon {
    font-size: 4rem;
    filter: drop-shadow(0 4px 3px rgb(0 0 0 / 0.07)) drop-shadow(0 2px 2px rgb(0 0 0 / 0.06));
}

/* 响应式调整 */
@media (max-width: 640px) {
    .platform-icon {
        font-size: 3rem;
    }
    
    .section {
        padding: 3rem 0;
    }
    
    h1 {
        font-size: 1.75rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    h3 {
        font-size: 1.25rem;
    }
}

/* 打印样式 */
@media print {
    .navbar,
    .footer,
    .download-btn,
    .btn {
        display: none !important;
    }
    
    body {
        background: white;
    }
    
    .section {
        padding: 1rem 0;
    }
}