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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    line-height: 1.8;
    font-size: 16px;
    color: #333;
    background-color: #f8fafc;
}

/* 通用链接样式 */
a {
    text-decoration: none;
    color: #2563eb;
    transition: all 0.3s ease;
}

a:hover {
    color: #1d4ed8;
}

/* 通用动画 */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

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

/* 通用组件样式 */
.preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.98);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    transition: opacity 0.3s ease;
    visibility: hidden;
    opacity: 0;
}

.preloader.loaded {
    opacity: 0;
    pointer-events: none;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(37, 99, 235, 0.2);
    border-top-color: #2563eb;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.scroll-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 40px;
    height: 40px;
    background: #2563eb;
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-to-top:hover {
    background: #1d4ed8;
    transform: translateY(-3px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

/* 通用表单样式 */
.form-group {
    margin-bottom: 1rem;
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #e2e8f0;
    border-radius: 0.375rem;
    transition: all 0.3s ease;
    font-size: 16px;
}

.form-control:focus {
    border-color: #2563eb;
    box-shadow: 0 0 0 2px rgba(37,99,235,0.2);
    outline: none;
}

/* 通用按钮样式 */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 0.375rem;
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 16px;
}

.btn-primary {
    background: #2563eb;
    color: white;
    border: none;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37,99,235,0.2);
}

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

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 2rem; }

.p-1 { padding: 0.25rem; }
.p-2 { padding: 0.5rem; }
.p-3 { padding: 1rem; }
.p-4 { padding: 1.5rem; }
.p-5 { padding: 2rem; }

/* 响应式容器 */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* 响应式网格系统 */
.row {
    display: flex;
    flex-wrap: wrap;
    margin: -0.5rem;
}

.col {
    flex: 1;
    padding: 0.5rem;
}

/* 响应式断点 */
@media (max-width: 1200px) {
    .container {
        max-width: 960px;
    }
}

@media (max-width: 992px) {
    .container {
        max-width: 720px;
    }
}

@media (max-width: 768px) {
    .container {
        max-width: 540px;
    }
    .col {
        flex: 0 0 100%;
    }
}

@media (max-width: 576px) {
    .container {
        max-width: 100%;
    }
}