* {
    box-sizing:border-box;
}

body {
    display: flex;
    justify-content: center;
    align-items: space-between;
    min-height: 100vh;
    margin: 0;
}
.game {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}
.game-letters {
    list-style-type:none;
    margin:10px auto;
    padding:0;
    max-width:1200px;
    text-align:center;
}
.game-letter {
    --color: rgba(100,100,100,1);
    display:inline-block;
    width: 4rem;
    height: 4rem;
    margin:0.3rem;
    cursor:pointer;
    text-transform:uppercase;
    font-size: 2rem;
    border-radius: 4px;
    font-family: sans-serif;
    text-align:center;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    background: none;
    border: 2px solid var(--color);
    color: var(--color);
}
.game-letter:disabled {
    --color: rgba(100,100,100,0.4);
    cursor:default;
}
.game-letter:not(:disabled):hover {
    --color: rgba(50, 50, 50, 0.8);
    background: gold;
}
.game-sentence {
    padding:0;
    margin:0;
    width:100%;
    text-align:center;
}
.game-sentence-box {
    text-transform: uppercase;
    width: 5rem;
    height: 5rem;
    border-bottom: 3px solid #333;
    margin: 1rem 0.5rem 2rem;
    font-size: 3rem;
    font-family: sans-serif;
    font-weight: bold;
    color: #333;
    vertical-align: top;
    display: inline-flex;
    justify-content: center;
    align-items: center;
}
.game-sentence-box-space {
    border: 0;
    background: none;
    box-shadow: none;
}
.game-attempts {
    margin:1rem 0;
    font-size: 1.6rem;
    font-weight: bold;
    font-family: sans-serif;
    text-align: center;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 4rem;
    height: 4rem;
    border-radius: 50%;
    background: #fff;
    color:#333;
    border:1px solid #ddd;
}

button.button,
input[type=button].button,
input[type=submit].button {
    display: block;
    max-width: 20em;
    text-align: center;
    padding: 1.3em 3em;
    font-weight: bold;
    font-size: 1.1rem;
    color: #FFF;
    text-decoration: none;
    margin: 2em auto;
    background: tomato;
    border-radius: 3em;
    line-height: 1.1em;
    text-shadow: none;
    transition: 0.5s background-color, 0.5s box-shadow;
    box-shadow: 0 2px 5px rgba(255, 99, 71, 0.4);
    border:0;
    cursor: pointer;
}