style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
}

.title {
    position: fixed;
    top: 10px;
    left: 10px;
}

form {
    background: #111;
    padding: 10px;
    border-radius: 7px;
    box-shadow: 0 0 7px #000;
}

form div {
    width: 250px;
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

form label {
    color: #fff;
    font-size: 20px;
}

form textarea, form input {
    width: 150px;
    padding: 7px;
    outline: none;
    border-radius: 2px;
    border: 2px solid #fff;
    transition: border .5s ease;
}

form textarea:focus, form input:focus {
    border: 2px solid #111;
}

form button {
    padding: 7px;
    border: none;
    outline: none;
    cursor: pointer;
    border-radius: 3px;
    background: #2b3083;
    color: #fff;
    transition: all .5s ease;
}

form button:hover, form button:focus {
    opacity: 0.7;
}

form textarea {
    resize: vertical;
    min-height: 50px;
    max-height: 100px;
}

.alertCont {
    width: 100vw;
    height: 100vh;
    top: 0;
    left: -100vw;
    position: fixed;
    background: rgba(0, 0, 0, 0.575);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all .5s ease;
}

.alert {
    padding: 10px;
    background: #111;
    border-radius: 2px;
    color: #fff;
}