darkmode.css

* {
 transition: 240ms ease-in;
}

body {
    background-color: #171717;
}

.container {
    width: 250px;
    height: 250px;
    padding: 50px;
    margin-left: 50%;
    margin-right: 50%;
    border-radius: 8px;
    background-color: #121212;
    transform: translate(-50%, 20%);
    box-shadow: 0px 0px 30px #111;
}

.profile-image {
    top: -100px;
    width: 100px;
    height: 100px;
    margin-left: 50%;
    margin-right: 50%;
    border-radius: 50%;
    position: relative;
    background-size: cover;
    transform: translateX(-50%);
    border: 2px solid dodgerblue;
    box-shadow: 0px 0px 10px #111;
    filter: brightness(0.8) contrast(2.0);
    background-image: url(./images/profile.jpg);
}

.profile-info {
    top: -100px;
    position: relative;
    text-align: center;
}

.profile-info h2 {
    color: white;
    font-size: 30px;
    font-weight: bold;
    margin: 10px 0px 0px 0px;
    font-family: 'Segoe UI', sans-serif;
}

.profile-info p {
    color: #aaa;
    font-size: 14px;
    margin: 2px 0px 0px 0px;
    font-family: 'Segoe UI', sans-serif;
}

.light-dark {
    display: flex;
    margin-left: 50%;
    margin-right: 50%;
    justify-content: space-evenly;
    transform: translate(-50%, 20%);
}

.light-dark button {
    border: none;
    outline: none;
    margin-right: 5px;
    border-radius: 4px;
    font-weight: medium;
    padding: 0.5rem 1.5rem;
    font-family: 'Segoe UI', sans-serif;
}

.light-dark .light {
    color: black;
    background-color: #eee;
}

.light-dark .black {
    color: white;
    background-color: #171717;
}

.light-dark .light:hover {
    background-color: #ddd;
}

.light-dark .black:hover {
    background-color: #333;
}