style.css

 @import url('https://fonts.googleapis.com/css2?family=Barlow+Semi+Condensed:wght@600;700&display=swap');

 *
{
    padding: 0;
    margin: 0;
    max-width: 100%;
    display: block;
    color: white;
}
body {
    background-image: linear-gradient( hsl(214, 47%, 23%), hsl(237, 49%, 15%));
    width: 100vw;
    height: 100vh;
    font-family: 'Barlow Semi Condensed', sans-serif;
}
header {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}
.score-container {
    background-color: white;
    width: 120px;
    height: 90px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}
.score-container span {
    color: hsl(229, 64%, 46%);
    text-transform: uppercase;
    font-size: small;
    letter-spacing: 1px;
    font-weight: 700;
}
.score {
    color: hsl(217, 16%, 45%);
    font-weight: 600;
    font-size: 50px;
    border: none;
    background-color: white;
}
.header {
    border: solid 3px hsl(217, 16%, 45%);
    width: 50vw;
    border-radius: 8px;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 20px 0px;
}
main {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
}
.game-body {
    position: relative;
    width: 40%;
    height: 30%;
    display: inline-flex;
    justify-content: center;
    align-items: center;  
} 
.bg-triangle {
    margin-top: 50px;
    width: 65%;
    height: 65%;
}
.circle-paper, .circle-rock, .circle-scissors {
    width: 75%;
    height: 75%;
    border-radius: 50%;
    background-color: white;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}
.icon-paper, .icon-scissors, .icon-rock {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}
.big-paper-circle, .big-circle-scissors, .big-circle-rock {
    position: absolute;
    border-radius: 50%;
    width: 11rem;
    height: 11rem;
    transition: all 0.5s ease-in-out;
    overflow: hidden;
    cursor: pointer;
}
.big-paper-circle:hover, .big-circle-scissors:hover, .big-circle-rock:hover {
    width: 11.5rem;
    height: 11.5rem;
}
.big-paper-circle {
    top: 0;
    left: 0;
    background-image: linear-gradient(hsl(230, 89%, 62%), hsl(230, 89%, 65%));
}
.big-circle-scissors {
    top: 0;
    right: 0;
    background-image: linear-gradient(hsl(39, 89%, 49%), hsl(40, 84%, 53%));
}
.big-circle-rock {
    bottom: 0;
    left: 31%;
    background-image: linear-gradient(hsl(349, 71%, 52%), hsl(349, 70%, 56%));
}
.rules {
    text-transform: uppercase;
    position: absolute;
    bottom: 10px;
    right: 20px;
    border: solid 2px hsl(217, 16%, 45%);
    padding: 10px 40px;
    border-radius: 10px;
    cursor: pointer;
}
.rules-container {
    background-color: white;
    width: 20%;
    height: 55%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 20px;
    border-radius: 10px;
    z-index: 22;
}
.rules-container h2 {
    text-transform: uppercase;
    color: hsl(229, 25%, 31%);
    position: absolute;
    top: 20px;
    font-weight: 700;
}
.icon-close {
    position: absolute;
    right: 0;
    top: 20px;
    right: 20px;
    cursor: pointer;
}
.image-rules {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    margin-top: 10%;
    width: 80%;
}
.overlay{
    position: fixed;
    top: 0px;
    left: 0px;
    width: 100%;
    height: 100vh;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1;   
}
aside {
    display: none;
}
.computerchoice, .mychoice {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    animation: test 0.5s forwards ease-in 1s; 
}
.mychoice {
    animation: test2 0.5s forwards ease-in 1s;
}
.computerchoice h4, .mychoice h4 {
    text-transform: uppercase;
    margin: 50px 50px;
}
.selection {
   align-items: center;
   display: none;
}   
.choosepaper, .comppaper, .chooserock, .comprock, .choosescissors, .compscissors {
    position: relative;
    border-radius: 50%;
    width: 12rem;
    height: 12rem;
    transition: all 0.5s ease-in-out;
    overflow: hidden;
    cursor: pointer;
    background-image: linear-gradient(hsl(230, 89%, 62%), hsl(230, 89%, 65%))
}
.chooserock, .comprock {
    background-image: linear-gradient(hsl(349, 71%, 52%), hsl(349, 70%, 56%));
}
.choosescissors, .compscissors{
    background-image: linear-gradient(hsl(39, 89%, 49%), hsl(40, 84%, 53%));
}
.comppaper, .comprock, .compscissors {
    display: none;
}
.bckgrd {
    width: 11rem;
    height: 11rem;
    border-radius: 50%;
    background-color: hsl(237, 49%, 15%);
}
.results {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
}
.results-mobile {
    display: none;
}
.playagain-btn {
    color:  hsl(217, 16%, 45%);
    width: 12.5rem;
    height: 3.125rem;
    border-radius: 10px;
    text-transform: uppercase;
    font-weight: 600;
    cursor: pointer;
    display: none;
}
.playagain-btn:hover {
    color: hsl(349, 71%, 52%);
}
.win-lose {
    font-size: 40px;
    font-weight: 600;
    text-transform: uppercase;
    margin: 20px 0;
}
.youpicked-mobile, .mobile {
    display: none;
}
@keyframes test {
    0% {
        transform: translateX(0px);
    }
    50% {
        transform: translateX(20px);
    }
    100% {
        transform: translateX(40px);
    }
}  
@keyframes test2 {
    0% {
        transform: translateX(0px);
    }
    50% {
        transform: translateX(-20px);
    }
    100% {
        transform: translateX(-40px);
    }
}
.d-none {
    display: none;
}
.d-flex {
    display: flex;
}
@media only screen and (max-width: 1024px) {
    .big-paper-circle, .big-circle-scissors, .big-circle-rock {
        width: 45%;
        height: 55%;
    }
    .bg-triangle {
        width: 80%;
        height: 80%;
    }
    .icon-paper, .icon-rock, .icon-scissors {
        height: 40%;
    }
    .big-circle-rock {
        left: 27%;
    }
    .rules-container {
        width: 50%;
        height: 40%;
    }
    .rules-container h2 {
        left: 10%;
        font-weight: 700;
    }
    .icon-close {
        right: 10%;
    }
    .header {
        width: 70vw;
    }
}
@media (height: 600px) {
    .rules-container {
        height: 80%;
    }
}
@media only screen and (max-width: 767px) {
    .choosepaper, .comppaper, .chooserock, .comprock, .choosescissors, .compscissors {
        width: 10rem;
        height: 10rem;
    }
    .computerchoice h4, .mychoice h4  {
        margin: 0;
    }
    .results {
        display: none;
    }
    .results-mobile {
        display: inline-flex;
        flex-direction: column;
        align-items: center;
    }
    .playagain-btn-mobile {
        color:  hsl(217, 16%, 45%);
        width: 12.5rem;
        height: 3.125rem;
        border-radius: 10px;
        text-transform: uppercase;
        font-weight: 600;
        cursor: pointer;
        display: none;
    }
    main {
        flex-direction: column;
    }
    .win-lose-mobile {
        font-size: 40px;
        font-weight: 600;
        text-transform: uppercase;
        margin: 20px 0;
    }
    .big-paper-circle, .big-circle-scissors, .big-circle-rock {
        width: 6.5rem;
        height: 6.5rem;
    }
}
@media only screen and (max-width: 520px) {
    .bg-triangle {
        width: 100%;
        height: 100%;
    }
    .big-paper-circle, .big-circle-scissors, .big-circle-rock {
        width: 50%;
        height: 50%;
    }
    .big-paper-circle {
        left: -10px;
    }
    .big-circle-scissors {
        right: -10px;
    }
    .choosepaper, .comppaper, .chooserock, .comprock, .choosescissors, .compscissors {
        width: 7.5rem;
        height: 7.5rem;
    }
    .youpicked-mobile, .mobile {
        display: block;
        text-transform: uppercase;
        font-size: 12px;
    }
    .computerchoice h4, .mychoice h4 {
        display: none;
    }
    .computerchoice{
        animation: test-mobile 0.5s forwards ease-in 1s;
    }
    .mychoice {
        animation: test-mobile2 0.5s forwards ease-in 1s;
    }
    @keyframes test-mobile {
        0% {
            transform: translateX(0px);
        }
        50% {
            transform: translateX(10px);
        }
        100% {
            transform: translateX(20px);
        }
    } 
    @keyframes test-mobile2 {
        0% {
            transform: translateX(0px);
        }
        50% {
            transform: translateX(-10px);
        }
        100% {
            transform: translateX(-20px);
        }
    } 
    .rules {
        padding: 10px 30px;
        right: 35%;
    }
    .overlay {
        background-color: white;
    }
    .icon-close {
        right: 45%;
        top: 90%;
    }
    .rules-container {
        width: 200px;
        height: 20rem;
    }
    .rules-container h2 {
        left: 35%;
    }
    .header {
        width: 80vw;
    }
    .bckgrd {
        width: 7.5rem;
        height: 7.5rem;
    }
    .game-body {
        width: 90%;
    }
}