style.css

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;700;900&display=swap');

@media (max-width: 300px) {
    #buttons {
        display: flex;
        flex-direction: column;
        margin-left: 50px;
        margin-right: 50px;
    }
}

@media (min-width: 350px) {
    #buttons {
        display: block;
        margin: auto;
    }
}

body {
    display: flex;
    flex-direction: column;
    text-align: center;
    font-family: 'Inter', sans-serif;
    transition: 0.5s ease-in-out;
}

h1 {
    font-weight: 400;
    font-size: 20px;
    margin-top: 200px;
}

input {
    border: none;
    background-color: rgb(236, 236, 236);
    border-radius: 5px;
    padding: 8px;
    width: 100px;
}

button {
    border: none;
    color: whitesmoke;
    background-color: #0f0f0f;
    padding: 10px 20px 10px 20px;
    border-radius: 5px;
    vertical-align: middle;
}

#overlay {
    position: fixed;
    display: none;
    width: 100%;
    height: 100%;
    top: 0; 
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0,0,0,0.8);
    z-index: 2;
}

#modal {
    display: none;
    position: fixed;
    top: 40%;
    left: 50%;
    margin-top: -100px;
    margin-left: -130px;
    padding: 20px;
    background-color: #ffffff;
    border-radius: 8px;
    text-align: center;
    z-index: 3;
}

#save {
    width: 100%;
}

#time {
    font-size: 100px;
    font-weight: 700;
}