style.css

@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@100&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Caveat&family=Pacifico&display=swap');
body {
    font-family: 'Roboto', sans-serif;
    background: url('./public/background.jpg');
    background-size: cover;
    display: grid;
    grid-template-columns: 0.5fr 0.5fr;
    grid-template-rows: 150px 0.1fr 80px;
}

header {
    grid-column: 1/3;
    font-size: 3rem;
    text-align: center;
}

header h1 {
    margin: 0;
    color: rgb(185, 182, 115);
    font-family: monospace;
    text-shadow: 1px 2px 7px #79a8db;
    animation: h1-animate 2s infinite;
}

@keyframes h1-animate {
    0%,
    90%,
    100% {
        opacity: 1;
    }
    95% {
        opacity: 0;
    }
}

header quote {
    color: white;
    font-family: 'Caveat', cursive;
    font-size: 2rem;
    margin-left: 250px;
}

.container {
    width: 350px;
    height: 250px;
    background: linear-gradient(75deg, #6eb66e, #8b9baf, #c9b49a, #68ac68);
    border-radius: 20px;
    font-weight: bold;
    margin-top: 14.5%;
    margin-left: 35%;
    text-align: center;
    box-shadow: 5px 5px 50px #8b8680cc;
    transform: scale(1.2);
}

.unit {
    display: flex;
    justify-content: center;
    grid-gap: 130px;
    color: white;
    padding: 10px 0;
    border-top-left-radius: 20px;
    border-top-right-radius: 20px;
    background: rgba(0, 0, 161, 0.801);
}

.unit #us:hover,
.unit #si:hover {
    transition: .3s;
    transform: scale(1.1, 1) translateY(3px);
    cursor: pointer;
}

.form input[type="text"],
.form input[type="radio"],
.form input[type="submit"] {
    border-radius: 5px;
    background: rgb(211, 211, 211);
}

.age,
.size,
.btn {
    margin: 10px 0;
}

.gender>label {
    margin-right: 25px;
}

#fheight,
#fweight {
    margin-bottom: 10px;
    width: 100px;
}

.btn {
    display: flex;
    grid-gap: 25px;
    padding-left: 20%;
}

.btn>button {
    padding: 5px 7px;
    box-shadow: 2px 2px 5px #5c5955;
    font-size: 1.1rem;
    border-radius: 10px;
    background: rgb(211, 211, 211);
    cursor: pointer;
}

.btn>button:hover {
    transition: 0.3s;
    transform: translateY(4px);
}

.table {
    width: 400px;
    height: 300px;
    background: rgba(255, 255, 255, 0.199);
    border-radius: 20px;
    margin-top: 10%;
    box-shadow: 5px 5px 50px #8b8680cc;
    color: white;
}

.result {
    display: flex;
    justify-content: space-around;
    border-bottom: 1px double #8f806e;
}

.index {
    height: 40px;
    width: 7%;
    margin-left: 30px;
    margin-top: 15px;
    /*do dai 30-345*/
    transition: 1.5s;
    font-weight: bold;
}

.index img {
    width: 25px;
    filter: invert(90%);
}

.table .ruler {
    background: linear-gradient(90deg, rgba(255, 0, 0, 0.877) 12.9%, pink 14.8%, yellow 19.35%, rgb(0, 214, 0) 40.6%, rgb(16, 16, 247) 46.4%, magenta 70.9%, red 87%, rgb(163, 0, 27) 100%);
    width: 80%;
    height: 50px;
    margin-left: 10%;
    border-radius: 15px;
}

.table .infor {
    margin: 20px 10px;
}

footer {
    background: rgba(223, 223, 223, 0.281);
    grid-column: 1/3;
    margin-top: 25px;
    margin-left: 29%;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 40%;
    border-radius: 30px;
    color: white;
}