index.css

@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Inline+Text:wght@900&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Stencil+Text:wght@300&display=swap');

* {
    margin: 0;
    padding: 0;
}

:root {
    --bg-col: #3a093a;
    --text-col: #ffffff;
    --bg-light: #e0e0e0;
    --bg-dark: #1d1b1e;
}

body {
    background: linear-gradient(to bottom, var(--bg-dark) 30%, var(--bg-col));
    color: var(--text-col);
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    width: 100vw;
    height: 95vh;
    gap: 32px;
    margin-top: 5vh;
}

body.light {
    background: linear-gradient(to bottom, var(--bg-light) 30%, var(--bg-col));
}

h1 {
    font-family: 'Big Shoulders Inline Text', cursive;
    font-size: 3.5rem;
    letter-spacing: 1rem;
}

h4 {
    font-family: 'Big Shoulders Inline Text', cursive;
    font-size: 3.5rem;
    letter-spacing: 1rem;
    text-align: center;
}

p {
    font-family: 'Big Shoulders Stencil Text', cursive;
    font-weight: 300;
    font-size: 2rem;
}

li {
    font-family: 'Big Shoulders Stencil Text', cursive;
    font-weight: 300;
    font-size: 2rem;
}

main {
    overflow: hidden;
}

.glow {
    font-size: 80px;
    color: #fff;
    text-align: center;
    -webkit-animation: glow 1s ease-in-out infinite alternate;
    -moz-animation: glow 1s ease-in-out infinite alternate;
    animation: glow 1s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        text-shadow: 0 0 10px #fff, 0 0 20px #fff, 0 0 30px #e60073, 0 0 40px #e60073, 0 0 50px #e60073, 0 0 60px #e60073, 0 0 70px #e60073;
    }
    to {
        text-shadow: 0 0 20px #fff, 0 0 30px #ff4da6, 0 0 40px #ff4da6, 0 0 50px #ff4da6, 0 0 60px #ff4da6, 0 0 70px #ff4da6, 0 0 80px #ff4da6;
    }
}

@keyframes drop-glow {
    from {
        filter:
            drop-shadow(0 0 1px #fff)
            drop-shadow(0 0 2px #fff)
            drop-shadow(0 0 3px #e60073)
            drop-shadow(0 0 4px #e60073);
    }
    to {
        filter:
            drop-shadow(0 0 2px #fff)
            drop-shadow(0 0 3px #ff4da6)
            drop-shadow(0 0 4px #ff4da6)
            drop-shadow(0 0 5px #ff4da6);
    }
}

@keyframes box-glow {
    from {
        box-shadow:
            inset 0 0 5px #fff,
            inset 0 0 10px #fff,
            inset 0 0 15px #e60073,
            inset 0 0 20px #e60073,
            inset 0 0 25px #e60073,
            inset 0 0 30px #e60073,
            inset 0 0 35px #e60073,

            0 0 5px #fff,
            0 0 10px #fff,
            0 0 15px #e60073,
            0 0 20px #e60073,
            0 0 25px #e60073,
            0 0 30px #e60073,
            0 0 35px #e60073;
    }
    to {
        box-shadow:
            inset 0 0 5px #fff,
            inset 0 0 15px #ff4da6,
            inset 0 0 20px #ff4da6,
            inset 0 0 25px #ff4da6,
            inset 0 0 30px #ff4da6,
            inset 0 0 35px #ff4da6,
            inset 0 0 40px #ff4da6,

            0 0 5px #fff,
            0 0 15px #ff4da6,
            0 0 20px #ff4da6,
            0 0 25px #ff4da6,
            0 0 30px #ff4da6,
            0 0 35px #ff4da6,
            0 0 40px #ff4da6;
    }
}

#score-label {
    opacity: 0;
    transition: opacity ease-in 0.2s;
}

body.light #score-label {
    color: var(--bg-dark);
}

#score-label.show {
    opacity: 1;
}

.menu {
    position: fixed;
    bottom: 10vh;
    top: calc(10vh + 10rem);
    background-color: var(--bg-col);
    min-width: 400px;
    max-width: 95vw;
    display: flex;
    flex-direction: column;
    align-items: space-between;
    justify-content: flex-start;
    gap: 1rem;
    padding: 3rem 1.5rem;
    overflow: hidden;
    opacity: 0.9;
    border-radius: 25px;
    -webkit-animation: box-glow 1s ease-in-out infinite alternate;
    -moz-animation: box-glow 1s ease-in-out infinite alternate;
    animation: box-glow 1s ease-in-out infinite alternate;
    border: 14px double #ffffff;
}

.back-button {
    margin-top: auto;
}

button {
    all: unset;
    font-family: 'Big Shoulders Inline Text', cursive !important;
    padding: 0 2rem;
    align-self: center;
    flex-shrink: 1;
    cursor: pointer;
    font-size: 3rem;
    text-transform: uppercase;
    letter-spacing: 0.5rem;
    color: #999;
    user-select: none;
}

#send-score {
    justify-content: space-between;
}

#send-score .back-button {
    margin: unset;
}

#inp-container {
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-items: center;
    gap: 1em;
    font-size: 2.5rem;
}

.letter-inp {
    all: unset;
    width: 1ch;
    height: 1em;
    padding: 0.5rem 1rem;
    font-family: 'Big Shoulders Stencil Text', cursive;
    border-bottom: 3px solid #fff;
    text-align:center;
    text-transform: uppercase;
}

.letter-inp:focus {
    -webkit-animation: drop-glow 1s ease-in-out infinite alternate;
    -moz-animation: drop-glow 1s ease-in-out infinite alternate;
    animation: drop-glow 1s ease-in-out infinite alternate;
}

button:hover, button:focus {
    -webkit-animation: glow 1s ease-in-out infinite alternate;
    -moz-animation: glow 1s ease-in-out infinite alternate;
    animation: glow 1s ease-in-out infinite alternate;
    color: #fff;
}

#score-board ul {
    overflow-x: auto;
}

#score-board li {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    padding: 0 2rem;
}

#score-board span {
    font-family: 'Big Shoulders Stencil Text', cursive;
    font-weight: 300;
    font-size: 2rem;
    text-transform: uppercase;
    letter-spacing: 0.5rem;
}

#dark-check {
    display: flex;
    flex-direction: row-reverse;
    justify-content: space-between;
    align-items: center;
    font-family: 'Big Shoulders Stencil Text', cursive;
    font-weight: 300;
    font-size: 2rem;
    letter-spacing: 0.5rem;
}

#volume {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    font-family: 'Big Shoulders Stencil Text', cursive;
    font-weight: 300;
    font-size: 2rem;
    letter-spacing: 0.5rem;
}

#main-menu {
    gap: 2rem;
}

#main-menu button {
    font-size: 3.5rem !important;
}

#about-menu {
    padding: 2rem 3rem;
    gap: 0.5rem;
}

#about-menu ul {
    padding-left: 2rem;
}

#p5_loading {
    font-family: 'Big Shoulders Inline Text', cursive;
    font-size: 3rem;
    letter-spacing: 0.5rem;
    display: fixed;
    top: 50vh;
    left: 50vw;
    transform: translate3d(-50%, -50%, 0);
    -webkit-animation: glow 1s ease-in-out infinite alternate;
    -moz-animation: glow 1s ease-in-out infinite alternate;
    animation: glow 1s ease-in-out infinite alternate;
    color: #fff;
}