index.css

body {
    background: #231F20;
    text-align: center;
    font-family: Cursed Timer ULiL;
}

.container {
    display: flex;
    background: #004689;
    width: 600px;
    margin: 20px auto;
    flex-direction: column;
    align-items: center;
    border: 5px solid #FFFFFF;
    border-radius: 10px;
}

.first-board {
    display: flex;
}

.fouls {
    width: 149px;
    height: 36px;
    font-family: 'Verdana';
    color: #FFFFFF;
    font-size: 25px;
}

.fouls-count {
    width: 100px;
    height: 70px;
    background: #000000;
    font-size: 60px;
    color: #ED1C24;
    line-height: 80px;
    margin: 10px auto; 
    border-radius: 5px;
}

.btn-fouls {
    width: 40px;
    height: 40px;
    background: inherit;
    border: 2px solid #000000;
    border-radius: 5px;
    color: #FFFFFF;
    line-height: 30px;
    font-family: inherit;
}

#main {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.d_flex {
    display: flex;
    flex-direction: row;
    border-radius: 5px;
    border: 5px solid #FFFFFF;
    border-radius: 10px;
    background: #000000;
}

.time_input {
    background: inherit;
    font-family: inherit;
    width: 70px;
    height: 70px;
    font-size: 45px;
    color: #CEA704;
    line-height: 115px;
    margin: 5px 10px;
    border: none;
}

.symbol {
    font-family: inherit;
    color: white;
}

.btn {
    width: 40px;
    height: 40px;
    background: #004689;
    font-family: inherit;
    font-size: 10px;
    line-height: 30px;
    color: #FFFFFF;
    border: 2px solid white;
    border-radius: 5px;
    margin: 5px 5px;
    padding: 0;
}

.btn:hover {
    background: #000000;
}

.message {
    font-family: 'Verdana';
    color: #ED1C24;
    font-size: 35px;
}

.second-board {
    display: flex;
}

.team {
    width: 149px;
    height: 36px;
    font-family: 'Verdana';
    color: #FFFFFF;
    font-size: 40px;
    margin: 0;
}

.score {
    width: 155px;
    height: 120px;
    background: #000000;
    font-size: 80px;
    color: #ED1C24;
    line-height: 127px;
    margin: 30px 0; 
    border-radius: 5px;
}

.buttons {
    display: flex;
    width: 155px;
    height: 45px;
    justify-content: space-between;
}

.btn-score {
    width: 40px;
    height: 40px;
    background: inherit;
    border: 2px solid #000000;
    border-radius: 5px;
    color: #FFFFFF;
    line-height: 30px;
    font-family: inherit;
}

button:hover {
    background: #000000;
}

#period {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

#period h1 {
    font-size: 25px;
}

#period-count {
    width: 50px;
    height: 70px;
    background: #000000;
    font-size: 60px;
    color: #CEA704;
    line-height: 80px;
    margin: 10px 0 20px 0; 
    border-radius: 5px;
}


#btn-new-game {
    width: 100px;
    height: 40px;
    background: #000000;
    border: 2px solid #000000;
    border-radius: 5px;
    color: #FFFFFF;
    line-height: 30px;
    font-family: inherit;
    margin-bottom: 10px; 
}

#btn-new-game:hover {
    background: inherit;
}