body {
    font-family: Arial, Helvetica, sans-serif;
    text-align: center;
    background-image: url("./hearts.jpg");
    background-size: cover;
    background-repeat: no-repeat;
    background-color: #000000;
}

#content-box {
    width: min(100% - 50px, 400px);
    margin-inline: auto;
    height: 500px;
    background-color: whitesmoke;
    padding: 20px;
    margin: 0 auto;
    margin-top: 50px;
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
}



::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: hsl(0, 0%, 90%);
}

::-webkit-scrollbar-thumb {
    background: hsl(0, 0%, 80%);
}

::-webkit-scrollbar-thumb:hover {
    background: hsl(0, 0%, 75%);
}


.title {
    font-weight: bold;
}

input {
    height: 20px;
    border-radius: 5px;
    font-weight: bold;
}

#result-percentage {
    font-size: 50px;
    margin-block: auto;
    color: rgb(255, 145, 0);
    font-weight: bold;
}


.btn {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 13rem;
    height: 3rem;
    background-size: 300% 300%;
    backdrop-filter: blur(1rem);
    border-radius: 5rem;
    transition: 0.5s;
    animation: gradient_301 5s ease infinite;
    border: double 4px transparent;
    background-image: linear-gradient(#212121, #212121), linear-gradient(137.48deg, #ffdb3b 10%, #FE53BB 45%, #8F51EA 67%, #0044ff 87%);
    background-origin: border-box;
    background-clip: content-box, border-box;
}

#container-stars {
    position: fixed;
    z-index: -1;
    width: 100%;
    height: 100%;
    overflow: hidden;
    transition: 0.5s;
    backdrop-filter: blur(1rem);
    border-radius: 5rem;
}

strong {
    z-index: 2;
    font-family: 'Avalors Personal Use';
    font-size: 12px;
    letter-spacing: 5px;
    color: #FFFFFF;
    text-shadow: 0 0 4px white;
}

#glow {
    position: absolute;
    display: flex;
    width: 12rem;
}

.circle {
    width: 100%;
    height: 30px;
    filter: blur(2rem);
    animation: pulse_3011 4s infinite;
    z-index: -1;
}

.circle:nth-of-type(1) {
    background: rgba(254, 83, 186, 0.636);
}

.circle:nth-of-type(2) {
    background: rgba(142, 81, 234, 0.704);
}

.btn:hover #container-stars {
    z-index: 1;
    background-color: #212121;
}

.btn:hover {
    transform: scale(1.1)
}

.btn:active {
    border: double 4px #FE53BB;
    background-origin: border-box;
    background-clip: content-box, border-box;
    animation: none;
}

.btn:active .circle {
    background: #FE53BB;
}

#stars {
    position: relative;
    background: transparent;
    width: 200rem;
    height: 200rem;
}

#stars::after {
    content: "";
    position: absolute;
    top: -10rem;
    left: -100rem;
    width: 100%;
    height: 100%;
    animation: animStarRotate 90s linear infinite;
}

#stars::after {
    background-image: radial-gradient(#ffffff 1px, transparent 1%);
    background-size: 50px 50px;
}

#stars::before {
    content: "";
    position: absolute;
    top: 0;
    left: -50%;
    width: 170%;
    height: 500%;
    animation: animStar 60s linear infinite;
}

#stars::before {
    background-image: radial-gradient(#ffffff 1px, transparent 1%);
    background-size: 50px 50px;
    opacity: 0.5;
}

@keyframes animStar {
    from {
        transform: translateY(0);
    }

    to {
        transform: translateY(-135rem);
    }
}

@keyframes animStarRotate {
    from {
        transform: rotate(360deg);
    }

    to {
        transform: rotate(0);
    }
}

@keyframes gradient_301 {
    0% {
        background-position: 0% 50%;
    }

    50% {
        background-position: 100% 50%;
    }

    100% {
        background-position: 0% 50%;
    }
}

@keyframes pulse_3011 {
    0% {
        transform: scale(0.75);
        box-shadow: 0 0 0 0 rgba(0, 0, 0, 0.7);
    }

    70% {
        transform: scale(1);
        box-shadow: 0 0 0 10px rgba(0, 0, 0, 0);
    }

    100% {
        transform: scale(0.75);
        box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
    }
}



@media (max-width: 650px) {
    #result-percentage {
        font-size: 30px;
        margin-block: auto;

    }

    #result-message { 
        font-size: 18px;
    }
}