misskey-tools/src/frontend/style.scss

body {
    --primary: rgb(134, 179, 0);
    --shadow-color: rgba(0, 0, 0, 0.1);
}

.xarticle {
    margin: auto;
    max-width: 720px;
    overflow: hidden;
}

.skeleton {
    border-radius: var(--radius);
    background: var(--tone-1);
    position: relative;
    overflow: hidden;
    &::after {
        content: "";
        inset: 0;
        position: absolute;
        background: linear-gradient(90deg, transparent, var(--tone-2) 50%, transparent 100%);
        animation: 1.2s ease-out 0s infinite skeleton;
    }
}

.tab {
    display: flex;
    background: var(--panel);
    .item {
        position: relative;
        background: transparent;
        border: none;
        color: var(--fg);
        padding: calc(var(--margin) / 2) var(--margin);
        transition: background 0.2s ease;
        &.active {
            color: var(--primary);
            &::after {
                content: "";
                width: 100%;
            }
        }
        &:hover {
            background: var(--hover);
        }
        &::after {
            content: "";
            position: absolute;
            transition: width 0.2s ease;
            transform-origin: center center;
            display: block;
            bottom: 0;
            height: 2px;
            left: 0;
            right: 0;
            width: 0;
            background-color: var(--primary);
        }
    }
}

@keyframes skeleton {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(300%);
    }
}