style.css

*{
    padding: 0;
    margin: 0;
    font-family: "Poppins";
    box-sizing: border-box;
    border: none;
    outline: none;
}

body{
    background-color: #9873FE;
    background-image: linear-gradient(to bottom right, #5513fc, #49cedf);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh; 
}

.wrapper{
    width: 25em;
    height: 80%;
    background-color: white;
    padding: 2em;
    border-radius: 0.8em;
}

.app-details{
    display: flex;
    align-items: center;
    text-align: center;
    flex-direction: column;
}

.app-body{
    display: flex;
    flex-direction: column;
}

.app-icon{
    width: 11em;
    margin-bottom: 1em;
}

.app-title{
    font-size: 1.8em;
    background: #6731f0;
    background-image: linear-gradient(
        45deg,
        #CA4246 16.666%, 
        #E16541 16.666%, 
        #E16541 33.333%, 
        #F18F43 33.333%, 
        #F18F43 50%, 
        #8B9862 50%, 
        #8B9862 66.666%, 
        #476098 66.666%, 
        #476098 83.333%, 
        #A7489B 83.333%);

    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1em;
    cursor: pointer;
    animation: rainbow-text-simple-animation-rev 0.5s ease forwards;
}

.app-title:hover{
    background-color: #6731f0;
    animation: rainbow-text-simple-animation 0.5s ease-in forwards;
}


@keyframes rainbow-text-simple-animation-rev {
    0% {
        background-size: 650%;
    }
    40% {
        background-size: 650%;
    }
    100% {
        background-size: 100%;
    }
}

@keyframes rainbow-text-simple-animation {
    0% {
        background-size: 100%;
    }
    80% {
        background-size: 650%;
    }
    100% {
        background-size: 650%;
    }
}

.amount-input{
    border-bottom: 2px solid #fdcd12;
    font-size: 20px;
    margin-top: 0.2em;
    padding: 0.7em;
    transition: background-color 1s;
}

.amount-input:focus{
    background-color: #fdcd1220;
}

.error-message{
    display: none;
    color: red;
    padding: 0.5em 0 0 1em;
}

.dropdown{
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1em;
    margin: 2.5em 0 2em 0;
}

.currency{
    width: 100%;
    padding: 0.6em;
    font-size: 1em;
    border-radius: 0.2em;
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    background-image: url("arrow-down.svg");
    background-repeat: no-repeat;
    background-position: right 15px top 50%, center;
    background-size: 20px 20px;
    background-color: #f45eac;
    cursor: pointer;
    color: #ffffff;
}

.currency option {
    background-color: #ffffff;
    color: #02002c;
}

.button{
    cursor: pointer;
    padding: 0.8em;
    background-color: #3f7df1;
    color: white;
    border-radius: 0.3em;
    transition: background-color 1s;
}

.button:hover{
    background-color: #1360f0;
}

.button:active{
    background-color: #1c67f180;
    transition: 0.1s;
}

.wrapper .app-body .result{
    text-align: center;
    background-color: #0d8964; /* this is alternate color #801637*/
    padding: 0.6em;
    margin-top: 1.5em;
    text-transform: uppercase;
    font-size: 1.3em;
    color: rgb(255, 255, 255);
}

/* WIDTH BREAKPOINT */
@media(max-width: 480px) {
    .wrapper {
        width: 22em;
        min-height: 80%;
        padding: 1.5em
    }
    .app-icon {
        width: 9em;
    }
    .app-details > .app-title{
        font-size: 1.4em;
    }
    .app-body > .amount-text {
        font-size: 1em;
    }
    .app-body > .amount-input {
        font-size: 1.2em;
    }
    .wrapper > .app-body > .result{
        font-size: 1.2em;
        padding: 0.8em;
        margin-top: 1em;
    }
}

@media(max-width: 360px) {
    .wrapper {
        width: 19em;
        min-height: 70%;
        padding: 1.5em
    }
    .app-icon {
        width: 9em;
    }
    .app-details > .app-title{
        font-size: 1.2em;
    }
    .app-body > .amount-text {
        font-size: 0.8em;
    }
    .app-body > .amount-input {
        font-size: 1em;
    }
    .wrapper > .app-body > .result{
        font-size: 1.2em;
        padding: 0.8em;
        margin-top: 2em;
    }
}

/* HEIGHT BREAKPOINT */
@media(min-height: 800px) {
    .wrapper {
        height: 70%;
        width: 30em;
    }
}

@media(min-height: 900px) {
    .wrapper {
        height: 65%;
        width: 35em;
    }
}

@media(max-height: 720px) {
    .wrapper {
        height: 90%
    }
    .app-icon {
        width: 10em;
    }
    .app-details > .app-title{
        font-size: 1.3em;
    }
    .app-body > .amount-text {
        font-size: 1em;
    }
    .app-body > .amount-input {
        font-size: 1.2em;
    }
    .wrapper > .app-body > .result{
        font-size: 1.2em;
        padding: 1em;
        margin-top: 1.4em;
    }
}

@media(max-height: 600px) {
    .wrapper {
        height: 90%
    }
    .app-icon {
        width: 7em;
    }
    .app-details > .app-title{
        font-size: 1.2em;
    }
    .app-body > .amount-text {
        font-size: 0.8em;
    }
    .app-body > .amount-input {
        font-size: 1em;
    }
    .wrapper > .app-body > .result{
        font-size: 1.2em;
        padding: 1em;
        margin-top: 1.4em;
    }
}


@media (max-width: 480px) and (min-height: 800px) {
    .wrapper {
        height: 70%;
        width: 20em;
    }
    .wrapper > .app-body > .result{
        font-size: 1.2em;
        padding: 1em;
        margin-top: 4em;
    }
}

@media(max-width: 480px) and (max-height: 480px) {
    .wrapper {
        width: 18em;
        min-height: 80%;
        padding: 1.5em
    }
    .app-icon {
        width: 7em;
    }
    .app-details > .app-title{
        font-size: 1em;
    }
    .app-body > .amount-text {
        font-size: 0.6em;
    }
    .app-body > .amount-input {
        font-size: 0.8em;
    }
    .dropdown{
        margin: 1.4em 0 1.4em;
    }
    .currency{
        font-size: 0.8em;
    }
    .button{
        font-size: 0.8em;
    }
    .wrapper > .app-body > .result{
        font-size: 1em;
        padding: 0.6em;
        margin-top: 1.2em;
    }
}