Build a loading with HTML, CSS, Javascript

<div class="container">
    <div class="loading-container">
        <div class="loading"></div>
    </div>

    <p>Lorem ipsum dolor, sit amet consectetur adipisicing elit. 
    Quibusdam nostrum, repellendus enim eveniet deleniti eaque 
    animi suscipit, nihil, fugiat ducimus tenetur quas quam. 
    Tempore magnam corrupti earum consequatur, modi unde?</p> 
</div>

    * {
        box-sizing: border-box;
        padding: 0;
        margin: 0;
    }

    body {
        font-family: "Segoe UI", sans-serif;
        line-height: 1.5;
    }

    /* Container */
    .container {
        margin: 50px auto;
        width: 95%;
    }
    @media (min-width: 700px) {
        .container {
            width: 60%;
        }
    }

    /* Loading */
    .loading-container {
        background-color: #ffffff;
        position: fixed;
        z-index: 1000;
        height: 100%;
        width: 100%;
        bottom: 0;
        right: 0;
        left: 0;
        top: 0;
        display: flex;
        justify-content: center;
        align-items: center;
        transition: ease all 4s;
    }
    .loaded {
        visibility: hidden;
        opacity: 0;
    }
    .loading {
        border: 2px solid blue;
        border-radius: 50%;
        border-bottom: none;
        border-left: none;
        height: 50px;
        width: 50px;
        animation-name: loader;
        animation-duration: .5s;
        animation-iteration-count: infinite;
        animation-timing-function: linear;
    }
    @keyframes loader {
        0% {
            transform: rotate(0);
        }
        100% {
            transform: rotate(360deg);
        }
    }

    /* P */
    p {
        margin-bottom: 12px;
    }

window.addEventListener("load" , function(){
    document.querySelector(".loading-container").classList.add("loaded");
})