.loading-box {
    position: fixed;
    top: 0;
    left: 0;
    background: #161616;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    font: 12px normal Verdana, Arial, Helvetica, sans-serif;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.3s ease-out, visibility 0.3s ease-out;
    z-index: 9999;
}
.loading-box.fade-out {
    opacity: 0;
    visibility: hidden;
}
h1.loadingtext {
    text-align: center;
    text-transform: uppercase;
    font-family: 'Nunito', sans-serif;
    font-size: 4.6875em;
    color: transparent;
    letter-spacing: 0.01em;
}
h1.loadingtext span {
    text-shadow: 0 0 2px rgba(22, 22, 22, 0.9), 0 15px 25px rgba(0, 0, 0, 0.3), 0 -2px 3px rgba(0, 0, 0, 0.1), 0 -5px 10px rgba(22, 22, 22, 0.5), 0 5px 10px rgba(0, 0, 0, 0.3), 0 3px 4px rgba(22, 22, 22, 0.2), 0 0 20px rgba(22, 22, 22, 0.45);
    -webkit-animation: letters 0.85s ease-in-out infinite alternate;
    -moz-animation: letters 0.85s ease-in-out infinite alternate;
    -ms-animation: letters 0.85s ease-in-out infinite alternate;
    animation: letters 0.85s ease-in-out infinite alternate;
    -webkit-animation-delay: 0;
    -moz-animation-delay: 0;
    -o-animation-delay: 0;
    animation-delay: 0;
}
h1.loadingtext span:nth-child(2) {
    -webkit-animation-delay: 0.15s;
    -moz-animation-delay: 0.15s;
    -o-animation-delay: 0.15s;
    animation-delay: 0.15s;
}
h1.loadingtext span:nth-child(3) {
    -webkit-animation-delay: 0.3s;
    -moz-animation-delay: 0.3s;
    -o-animation-delay: 0.3s;
    animation-delay: 0.3s;
}
h1.loadingtext span:nth-child(4) {
    -webkit-animation-delay: 0.45s;
    -moz-animation-delay: 0.45s;
    -o-animation-delay: 0.45s;
    animation-delay: 0.45s;
}
h1.loadingtext span:nth-child(5) {
    -webkit-animation-delay: 0.6s;
    -moz-animation-delay: 0.6s;
    -o-animation-delay: 0.6s;
    animation-delay: 0.6s;
}
h1.loadingtext span:nth-child(6) {
    -webkit-animation-delay: 0.75s;
    -moz-animation-delay: 0.75s;
    -o-animation-delay: 0.75s;
    animation-delay: 0.75s;
}
h1.loadingtext span:nth-child(7) {
    -webkit-animation-delay: 0.9s;
    -moz-animation-delay: 0.9s;
    -o-animation-delay: 0.9s;
    animation-delay: 0.9s;
}

@keyframes letters {
    to {
        /* 提升浅灰和黑色阴影的透明度，让整体更明亮 */
        text-shadow: 0 0 2px rgba(220, 224, 228, 0.4), 0 0 3px rgba(0, 0, 0, 0.05), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(255, 255, 255, 0), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(255, 255, 255, 0), 0 0 0 rgba(255, 255, 255, 0);
    }
}
@-moz-keyframes letters {
    to {
        /* 同标准动画，保持Firefox兼容性的亮度一致 */
        text-shadow: 0 0 2px rgba(220, 224, 228, 0.4), 0 0 3px rgba(0, 0, 0, 0.05), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(255, 255, 255, 0), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(255, 255, 255, 0), 0 0 0 rgba(255, 255, 255, 0);
    }
}
@-webkit-keyframes letters {
    to {
        /* 将深灰色（22,22,22）改为浅灰色，同时提升透明度 */
        text-shadow: 0 0 2px rgba(220, 224, 228, 0.4), 0 0 3px rgba(0, 0, 0, 0.05), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(0, 0, 0, 0), 0 0 0 rgba(0, 0, 0, 0);
    }
}