/* 关键CSS - 首屏渲染所需的最小样式集 */

/* 基础布局 - 蓝白主题 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.5;
    color: #1e3a8a;
    background-color: #ffffff;
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 50;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(8px);
    transition: all 0.3s ease;
}

/* 容器 */
.container {
    width: 100%;
    max-width: 1280px;
    margin-left: auto;
    margin-right: auto;
    padding-left: 1rem;
    padding-right: 1rem;
}

/* 标题样式 */
h1, h2, h3 {
    margin: 0;
    font-weight: 700;
    line-height: 1.2;
}

h1 {
    font-size: 2.25rem;
    margin-bottom: 1rem;
}

h2 {
    font-size: 1.875rem;
    margin-bottom: 0.75rem;
}

/* 按钮基础样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 0.375rem;
    padding: 0.5rem 1rem;
    font-weight: 500;
    transition: all 0.2s ease;
    cursor: pointer;
}

.btn-primary {
    background-color: #007BFF;
    color: white;
}

.btn-primary:hover {
    background-color: #0067D6;
}

/* 文本渐变效果 */
.text-gradient {
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

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

/* 响应式布局基础 */
@media (min-width: 640px) {
    .container {
        padding-left: 1.5rem;
        padding-right: 1.5rem;
    }
}

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

/* 首屏图片占位符 - 蓝白主题 */
.hero-image-placeholder {
    width: 100%;
    height: 0;
    padding-bottom: 56.25%; /* 16:9 宽高比 */
    background-color: #EAF6FF;
    border-radius: 0.5rem;
}