.alert {
    padding: 20px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-family: Arial, sans-serif;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    animation: slideIn 0.3s ease-in-out;

    /* 居中定位 */
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 9000000;

    /* 可选:限制最大宽度 */
    max-width: 90%;
    width: fit-content;
}

@keyframes slideIn {
    from {
        transform: translateX(-50%) translateY(-100%);
    }
    to {
        transform: translateX(-50%) translateY(0);
    }
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-warning {
    background-color: #fff3cd;
    color: #856404;
    border: 1px solid #ffeeba;
}

.alert-info {
    background-color: #cce5ff;
    color: #004085;
    border: 1px solid #b8daff;
}

.close-btn {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    font-size: 20px;
    padding: 0 5px;
    opacity: 0.5;
    transition: opacity 0.2s;
}

.close-btn:hover {
    opacity: 1;
}