:root
{
    --bg-color--: #190f2f;
    --color-1--: #35374B;
    --color-3--: #344955;
    --color-2--: #50727B;
    --color-4--: #78A083;
}


body 
{
    color: #fff;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    background-color: var(--bg-color--);
}

.main-box 
{
    width: 576px;
    height: 760px;
    /* border: 2px solid black; */
    border-radius: 6px;
    overflow: hidden;
}

.main-box .box-1
{
    background-image: url(guess\ number.jpeg);
    background-repeat: no-repeat;
    background-position: top center;
    background-color: var(--bg-color--);
    width: 100%;
    height: 100%;
    /* border: 2px solid black; */
    border-radius: 6px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.main-box .box-1 #btn-1
{
    font-size: 25px;
    width: 60%;
    height: 100px;
    border: none;
    cursor: pointer;
    border-radius: 4px;
}

.main-box .box-2
{
    background-color: var(--color-2--);
    width: 100%;
    height: 100%;
    /* border: 2px solid black; */
    border-radius: 6px;
    text-align: center;
    overflow: hidden;
}

.main-box .box-2 .box-3
{
    margin-left: 9.5%;
    margin-top: 50px;
    width: 80%;
    height: 35%;
    /* border: 2px solid black; */
    border-radius: 6px;
    display: flex;
    justify-content: center;
}

.main-box .box-2 .box-3 .box-4, .box-5
{
    width: 50%;
    height: 100%;
    /* border: 2px solid black; */
    border-radius: 4px;
}

.main-box .box-2 #btn-2
{
    /* margin-left: 9.5%; */
    margin: auto;
    color: #fff;
    background-color: var(--color-3--);
    border: none;
    width: 60%;
    height: 100px;
    border-radius: 6px;
    font-size: 25px;
    cursor: pointer;
}

.main-box .box-2 #btn-2:hover
{
    background-color: var(--color-1--);
}

.main-box .box-2 .box-3 .para-1
{
    text-decoration: underline;
}

.main-box .box-2 .box-3 .box-4 #box-4-1
{
    font-size: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 80%;
    height: 60%;
    margin: auto;
    border: 1px solid var(--color-4--);
    border-radius: 50%;
    background-color: var(--color-3--);
}

.main-box .box-2 .box-3 .box-5 #box-5-1
{
    font-size: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 80%;
    height: 60%;
    margin: auto;
    border: 1px solid var(--color-4--);
    border-radius: 50%;
    background-color: var(--color-3--);
}

.main-box .box-2 #box-6
{
    font-size: 25px;
    color: #fff;
    background-color: var(--bg-color--);
    margin: auto;
    width: 80%;
    height: 15%;
    /* border: 2px solid black; */
    border-radius: 6px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.main-box .box-2 .input-1
{
    background-color: #fff;
    text-align: center;
    font-size: 18px;
    height: 70px;
    width: 50%;
    border: none;
    margin: auto;
    /* margin-left: 9.5%; */
    margin-top: 30px;
    border-radius: 6px;
}

.main-box .box-2 .input-1:focus
{
    outline: none;
}

.main-box .box-2 .box-7
{
    background-color: var(--color-1--);
    /* position: absolute; */
    /* margin-bottom: 0; */
    width: 100%;
    height: 50px;
    margin-top: 50px;
    display: flex;
    justify-content: center;
    align-items: center;
    /* border: 2px solid black; */
}

.main-box .box-2 #btn-3
{
    margin: auto;
    display: none;
    color: #fff;
    background-color: var(--color-3--);
    border: none;
    width: 60%;
    height: 100px;
    border-radius: 6px;
    font-size: 25px;
    cursor: pointer;
}