*, *::before, *::after {
    box-sizing: border-box;
    font-family: "Tahoma", sans-serif;
}

:root {
    --hue-neutral: 200;
    --hue-wrong: 0;
    --hue-correct: 145;
}

body {
    --hue: var(--hue-neutral);
    padding: 0;
    margin: 0;
    display: flex;
    width: 100vw;
    height: 100vh;
    justify-content: center;
    align-items: center;
    background-color: hsl(var(--hue), 100%, 20%);
    background: transparent url("assets/smile.png") repeat scroll 0 0;
    background-size: 5%
}

body.correct {
    --hue: var(--hue-correct);
    background: transparent url("assets/correct.png") repeat scroll 0 0;
    background-size: 5%
}

body.wrong {
    --hue: var(--hue-wrong);
    background: transparent url("assets/wrong.png") repeat scroll 0 0;
    background-size: 5%
}

.container {
    width: 800px;
    max-width: 80%;
    background-color: white;
    border-radius: 5px;
    padding: 10px;
    box-shadow: 0 0 10px 2px;
    font-size: clamp(2rem, 3vw, 4rem)
}

h1 {
    text-align: center;
}

.btn-grid {
    display: grid;
    grid-template-columns: repeat(2, auto);
    gap: 10px;
    margin: 20px 0;
}

.score-btns {
    padding: 5px;
    display: grid;
    gap: 10px;

}

.btn {
    --hue: var(--hue-neutral);
    border: 1px solid hsl(var(--hue), 100%, 30%);
    background-color: hsl(var(--hue), 100%, 50%);
    border-radius: 5px;
    padding: 5px 10px;
    color: white;
    outline: none;
}

.btn:hover {
    border-color: black;
}

.restart-btn:hover {
    background-color: #333;
}

.btn.correct {
    --hue: var(--hue-correct);
    color: black;
}

.btn.wrong {
    --hue: var(--hue-wrong);
}

.start-btn, .next-btn, .restart-btn, .review-btn, .back-btn {
    font-size: 1.5rem;
    font-weight: bold;
    padding: 10px 20px;
}

.back-btn { 
    background-color: green;
}

.restart-btn {
    margin-top: 10px
}

.score {
    display: flex;
    justify-content: center; 
    font-size: 7vh;
    color: #333;   
}

.score > * {
    flex-grow: 1;
    flex-basis: 0;
    padding: 0 2vh;
    margin: 1vh 0;
}

.score > :first-child {
    text-align: right;
    border-right: .5vh solid #333
}

.progress-timer { 
    width: 100%;
    max-width: 400%;
    height: 20px;
    border-radius: 10px;
    background-color: gray;
    overflow: hidden;
    margin-bottom: 20px
}

#timer-bar {
    height: 100%;
    width: 100%;
    background-color: lightblue;
    transition: width 0.1s linear;
}

.review-container {
    width: 500px;
    height: auto;
    max-width: 80%;
    max-height: 80vh;
    background-color: yellowgreen;
    border-radius: 5px;
    padding: 10px;
    box-shadow: 0 0 10px 2px;
    overflow-y: auto;
    scroll-behavior: smooth;
    border: 9px solid green;
} 

.review-container::-webkit-scrollbar { 
    width: 5px;
}


.review-container::-webkit-scrollbar-button { 
    background: yellowgreen;
}

.review-container::-webkit-scrollbar-track { 
    background: yellowgreen;
}

.review-container::-webkit-scrollbar-thumb { 
    background: white;
    border-radius: 10px;
}

.hide {
    display: none;
}

summary {
    font-weight: bold;
    cursor: pointer;
    user-select: none;
    color: white;
}

summary::marker {
    content: '+ '
}


details[open] summary::marker {
    content: '- '
}

details {
    color: white;
    font-weight: normal;
    margin: 5px 
}

details.correct {
    border: 2px solid rgb(117, 223, 117);
    background-color: hsl(var(--hue-correct), 100%, 30%);
}

details.wrong { 
    border: 2px solid rgb(247, 171, 171);
    background-color: hsl(var(--hue-wrong), 100%, 30%);
}

/* 
details[open].correct {
    background-color: lime
}

details[open].wrong {
    background-color: red
} */