• 注入到 head 部分

<script>
    function addLoadedClassToParents(parentSelector, childSelector, loadedClass) {
        document.addEventListener('DOMContentLoaded', function () {
            var parentElements = document.querySelectorAll(parentSelector);
            parentElements.forEach(function (parentElement) {
                var childElement = parentElement.querySelector(childSelector);
                if (!childElement) {
                    return;
                }
                if (childElement) {
                    childElement.addEventListener('load', function () {
                        parentElement.classList.add(loadedClass);
                    });
                }
            });
        });
    }
    addLoadedClassToParents('thyuu-embed', 'iframe', 'loaded');
</script>

<style>
    :root {
        --thyuu-font-color: 0deg 0% 15%;
        --thyuu-nav-height: 4rem;
        --thyuu-edge-tb: var(--thyuu-nav-height);
        --thyuu-bg: hsl(var(--thyuu-font-color) / 4%);
        --thyuu-radius: 16px;
    }


    thyuu-embed {
        display: block;
        position: relative;
    }

    thyuu-embed iframe {
        width: 100%;
        transition: .5s .5s;
    }

    thyuu-embed:not(.loaded) iframe {
        opacity: 0;
        pointer-events: none;
    }

    thyuu-embed:not(.loaded):after {
        content: "";
        position: absolute;
        border-top: 2px solid;
        border-radius: 50%;
        width: 1em;
        aspect-ratio: 1;
        inset: auto 0 1.5em;
        margin: auto;
        pointer-events: none;
        animation: rotate 2s linear infinite;
    }

    .thyuu-music {
        width: 100%;
        height: 65px;
        outline: thin solid var(--thyuu-bg);
        background: var(--thyuu-bg);
        border-radius: var(--thyuu-radius);
        overflow: hidden;
    }

    .thyuu-music:is([data-type="nn_lists"], [data-type="nn_album"]) {
        height: 390px;
    }

    :is([theme="dark"], body.dark-color) .thyuu-music iframe {
        opacity: .6;
        mix-blend-mode: plus-lighter;
    }

    .thyuu-video {
        position: relative;
        display: flex;
        align-items: center;
        justify-content: center;
        max-width: 100%;
        max-height: calc(80vh - var(--thyuu-edge-tb));
        margin-inline: auto;
        outline: thin solid var(--thyuu-bg);
        color: white;
        background: #000;
        border-radius: var(--thyuu-radius);
        aspect-ratio: 16 / 9;
    }

    /* .thyuu-video:before {
    content: "\e8af";
    position: absolute;
    font-size: 6em;
    line-height: 1;
    opacity: .15;
} */
    .thyuu-video iframe {
        height: 100%;
        border-radius: inherit;
        align-self: flex-start;
        z-index: 2;
    }

    .thyuu-video[data-type="dy"] iframe:hover {
        height: calc(100% + 35px);
    }

    @media (max-width: 641px) {
        .thyuu-video.as-tb:not([data-type="dy"]) {
            aspect-ratio: 9 / 16;
        }

        .thyuu-video[data-type="dy"] {
            width: min(324px, 100%);
            max-height: none;
            margin-inline: auto;
            aspect-ratio: .4821;
            overflow: hidden;
        }
    }

    @keyframes rotate {
        from {
            transform: rotate(0deg)
        }

        to {
            transform: rotate(1turn)
        }
    }
</style>