ol {
    width: 80%;
    list-style: none;
}

ol li {
    font-size: 1.2rem;
    padding: 20px 30px;
    margin: 10px 0;
    background: rgb(230, 230, 230);
    z-index: 5;
    position: relative;
    cursor: pointer;
    transition: all .4s;
}
ol li::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    z-index: -1;
    transition: all .4s;
}

ol li:hover::before {
    width: 100%;
}
ol li:nth-child(1)::before {
    background: #4285f4;
}

ol li:nth-child(2)::before {
    background: #db4437;
}

ol li:nth-child(3)::before {
    background: #f4b400;
}

ol li:nth-child(4)::before {
    background: #0f9d58;
}
ol li:nth-child(5)::before {
    background: #191969;
}

ol li:hover {
    transform: translateX(20px);
}