404.css

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

body, html {
    height: 100%;
    font-family: Arial, sans-serif;
    color: #fff;
}

.container {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 2;
}

.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('res/404.png') no-repeat center center/cover;
    background-size: cover;
    z-index: 1;
}

.overlay::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.3);
}

h1 {
    font-size: 96px;
    margin-bottom: 20px;
}

p {
    font-size: 24px;
    margin-bottom: 40px;
}

.button {
    padding: 15px 30px;
    font-size: 18px;
    color: #fff;
    background-color: #007BFF;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    transition: background-color 0.3s;
}

.button:hover {
    background-color: #0056b3;
}