/* 基础样式 */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

h1 {
    color: white;
    text-align: center;
    font-size: 2.5rem;
    margin: 0;
    opacity: 0;
    transition: opacity 0.5s ease-in;
}

/* 加载器容器 */
.loader-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 0.5s ease-out;
}

/* 加载器样式 */
.loader {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

/* 旋转动画 */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 加载文本 */
.loading-text {
    margin-top: 20px;
    font-size: 1.2rem;
    color: #667eea;
    text-align: center;
}

/* 隐藏状态 */
.hidden {
    opacity: 0;
    pointer-events: none;
}

/* 显示内容 */
.content-visible {
    opacity: 1;
}