@font-face {
    font-family: 'Pixel';
    src: url('../fonts/Pixel.ttf');
}
html {
    height: 100%;
}
body {
    margin: 0;
    background-color: #0D262D;
    color: #fff;
    height: 100%;
}
* {
    box-sizing: border-box;
    font-family: 'Oswald', sans-serif;
}
.content {
    display: flex;
    min-height: 100%;
    text-align: center;
}
.content h1 {
    margin-top: 70px;
    margin-bottom: 30px;
    font-size: 25px;
}
[wm-flappy] {
    position: relative;
    height: 490px;
    width: 840px;
    margin: 15px;
    background-color: deepskyblue;
    overflow: hidden;
}
.game-over-display {
    box-sizing: border-box;
    width: 420px;
    height: 140px;
    border: 11px solid white;
    color: white;
    position: absolute;
    top: 140px;
    left: 200px;
    font-size: 45px;
    font-weight: bold;
    font-family: Pixel;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;    
}
.bird {
    position: absolute;
    width: 42px;
    left: calc(50% - 30px);
}
.pair-of-barriers {
    position: absolute;
    top: 0;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}
.barrier {
    display: flex;
    flex-direction: column;
    align-items: center;
}
.barrier .barrier-border {
    height: 20px;
    width: 90px;
    background: linear-gradient(90deg, #639301, #a5e82e);
    border: 2px solid #000;
}
.barrier .barrier-body {
    height: 105px;
    width: 75px;
    background: linear-gradient(90deg, #639301, #a5e82e);
    border-left: 2px solid #000;
    border-right: 2px solid #000;
}
.game-progress {
    position: absolute;
    top: 7px;
    right: 7px;
    font-family: Pixel;
    font-size: 50px;
    z-index: 100;
}
.instructions {
    display: flex;
    flex-direction: column;
    align-items: center;    
    box-sizing: border-box;
    width: 320px;    
    margin-top: 127px;
}
.instructions-button {
    box-sizing: border-box;
    width: 320px;
    height: 50px;
    border: 3px solid black;
    background: linear-gradient(90deg, #639301, #a5e82e);
    color: white;
    cursor: pointer;
    font-size: 14px;
    font-weight: bold;
    outline: none;
    transition: border 0.3s;
}
.instructions-button:hover {
    border-color: white;
}
.instructions-paragraph {
    box-sizing: border-box;
    width: 320px;
    color: white;
    border: 4px solid white;
    font-size: 15px;
    font-weight: bold;
    padding: 20px;   
}
p.button-active {
    visibility: visible;
}
p.button-no-active {
    visibility: hidden;
}