.preloader {
    position: fixed;
    z-index: 9999;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: transparent; /* 透明背景，避免遮住内容 */
    pointer-events: none;
}

.curtain {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #f4f6f9;
    z-index: 9999;
    display: flex; /* 关键：启用 Flex 布局 */
    justify-content: center; /* 水平居中 */
    align-items: center; /* 垂直居中 */
}

@keyframes slideUp {
    0% {
        transform: translateY(0);
    }

    100% {
        transform: translateY(-100%);
    }
}

.logo-shake {
    width: 60px;
    height: 60px;
    animation: shake 1.5s infinite;
}

@keyframes shake {
    0% {
        transform: translate(2px, 1px) rotate(0deg);
    }

    10% {
        transform: translate(-1px, -2px) rotate(-2deg);
    }

    20% {
        transform: translate(-3px, 0) rotate(3deg);
    }

    30% {
        transform: translate(0, 2px) rotate(0deg);
    }

    40% {
        transform: translate(1px, -1px) rotate(1deg);
    }

    50% {
        transform: translate(-1px, 2px) rotate(-1deg);
    }

    60% {
        transform: translate(-3px, 1px) rotate(0deg);
    }

    70% {
        transform: translate(2px, 1px) rotate(-2deg);
    }

    80% {
        transform: translate(-1px, -1px) rotate(4deg);
    }

    90% {
        transform: translate(2px, 2px) rotate(0deg);
    }

    100% {
        transform: translate(1px, -2px) rotate(-1deg);
    }
}