body {
    margin: 0;
    padding: 0;
    background-color: #87CEEB; /* 天蓝色背景 */
    font-family: 'Montserrat Alternates', sans-serif;
    font-style: normal;
    display: flex; /* 使用 Flexbox 布局 body */
    justify-content: center; /* 水平居中 */
    align-items: center; /* 垂直居中 */
    min-height: 100vh; /* 确保 body 至少占据整个视口高度 */
    text-align: center; /* 文本居中 */
    color: #333; /* 文字颜色 */
}

/* --- common style --- */
.hidden {
    display: none !important;
}

.base-tip{
   /* 置于页面最上方正中 背景金黄色*/
    position: absolute;
    top: 0;
    background-color: #FFD700;
    padding: 10px;
    border-radius: 10px;
    font-size: 20px;
    font-weight: bold;
    color: #333;
}

/* --- Logo Area--- */

.logo-container {
    display: flex;
    position: absolute;
    left: 10px;
    top: 10px;
}

.logo-image {
    max-width: 40%; /* Logo max width */
    height: auto;
    margin-bottom: 20px;
}

/* --- Login Info Area--- */
.login-info {
    position: absolute;
    right: 20px;
    top: 10px;
}

.login-info a {
    color: blue;
    text-decoration: none;
    font-size: 15px;
    font-weight: bold;
}

.login-info a:hover {
    color: red;
    cursor: pointer;
}


/* --- Footer Area--- */
.my-footer {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    font-size: 13px;
    color: #666;
    text-align: center;
    font-weight: bold;
}

.footer-imgs {
    display: flex;
    justify-content: center;
    height: 100px;
}


/* --- Blur --- */
.overlay {
    position: fixed; /* fix position and cover all screen */
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5); /* half transparency */
    backdrop-filter: blur(3px); /* add a blur effect */
    z-index: 100; /* make sure the layer is the highest */
}