@import url('https://fonts.googleapis.com/css2?family=Open+Sans&display=swap');

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Open Sans', sans-serif;
}

main {
    width: 100vw;
    height: 100vh;
}

.container {
    width: 100vw;
    height: 95vh;
    background: black;
    display: flex;
    justify-content: center;
    flex-direction: column;
    align-items: center;
}

.container h1 {
    margin-bottom: 0.8rem;
    color: #fff;
}

/* ######################################### winner span #################################### */
.container .winner {
    margin-bottom: 0.8rem;
    background: aqua;
    width: 250px;
    height: 50px;
    border-radius: 0.8rem;
    display: flex;
    justify-content: center;
    align-items: center;
    /* over-writing display property */
    display: none;
}

/* ######################### end of winner span ######################################### */

.container .box {
    width: 312px;
    height: 312px;
    background: #4479CB;
}

.container .box .common-row {
    display: flex;
}

.common-box {
    width: 100px;
    height: 94px;
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 5px;
    font-size: 2rem;
    background: black;
    color: #fff;
    transition: all 3s linear infinite;
}

.common-box:hover {
    box-shadow: 0 0 5px #fff;
    cursor: pointer;
}

.add {
    background: green;
}

/* ########################################## buttons ################################################## */
.common-button {
    padding: 0.5rem;
    margin-top: 0.8rem;
    border-radius: 1rem;
    border: none;
    cursor: pointer;
}

/*#################################### button-selection ######################## */
.selected_button {
    background: rgb(40, 117, 241);
    color: #fff;
    font-weight: bold;
}

/* ############################################## footer ##################################################### */
footer {
    width: 100vw;
    height: 5vh;
    background: rgb(40, 117, 241);
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
}

footer a {
    text-decoration: none;
    color: #fff;
}