* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    border: none;
}

body {
    margin: 0;
    padding: 0;
}

button {
    background-color: transparent;
    padding: 0;
    font-size: 1rem;
}

.bodyMain {
    width: 100vw;
    height: 100vh;
    display: flex;
    background-color: black;
}

.main {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
    align-items: center;

}

.main h1 {
    font-size: 3rem;
    color: white;
    margin-top: -50px;
}

.main h1 span {
    color: blue;
}

.sudokuBoard {
    display: grid;
    grid-template-columns: repeat(9, 60px);
    /* gap:5px; */
    /* margin-bottom: 20px; */
    

}

.sudokuBoard input {
    width: 60px;
    height: 60px;
    border: 1px solid rgb(0, 195, 255);
    text-align: center;
    font-size: 20px;
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
    color: white;
    background-color: black;
    transition: all 1s ease;
}

@media screen and (max-width:820px) {
    .sudokuBoard{
         display: grid;
         grid-template-columns: repeat(9, 50px);
     
    }
    .sudokuBoard input {
        width:50px;
        height:50px;
               box-sizing: border-box;
    }
}

.sudokuBoard input:nth-of-type(3n) {
    border-right: 5px solid rgba(0, 204, 255, 0.941);
}

.sudokuBoard input:nth-of-type(n+19):nth-of-type(-n+27),
.sudokuBoard input:nth-of-type(n+46):nth-of-type(-n+54),
.sudokuBoard input:nth-of-type(n+73):nth-of-type(-n+81) {
    border-bottom: 5px solid rgba(0, 204, 255, 0.941);
}

.sudokuBoard input:nth-of-type(1),
.sudokuBoard input:nth-of-type(10),
.sudokuBoard input:nth-of-type(19),
.sudokuBoard input:nth-of-type(28),
.sudokuBoard input:nth-of-type(37),
.sudokuBoard input:nth-of-type(46),
.sudokuBoard input:nth-of-type(55),
.sudokuBoard input:nth-of-type(64),
.sudokuBoard input:nth-of-type(73) {
    border-left: 5px solid rgba(0, 204, 255, 0.941);
}

.sudokuBoard input:nth-of-type(-n+9) {
    border-top: 5px solid rgba(0, 204, 255, 0.941);
}

.generate {
    background-color: #4CAF50;
    color: white;
    padding: 12px 15px;


}

.customInput {
    background-color: rgba(0, 204, 255, 0.941);
    color: white;
    padding: 12px 15px;

}

.solve {
    background-color: blue;
    color: white;
    padding: 12px 15px;


}

.createBoard {
    background-color: #f44336;
    color: white;
    padding: 12px 15px;


}

.buttons {
    max-width:500px;
    display:flex;
    flex-wrap:wrap;
    gap: 5px;
}

.generate:hover {
    background-color: #1e7e34;
}


.customInput:hover {
    background-color: rgb(15, 170, 209);
}

.solve:hover {
    background-color: rgb(9, 9, 213);
}

.createBoard:hover {
    background-color: #c61325;
}




button {
    cursor: pointer;
    font-weight: bold;
    border: none;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.navBtns button {
    width: 200px;
    padding: 15px;

}

.leftNav {
    /* display: flex; */
    flex-direction: column;
    gap: 25px;
    padding: 30px 20px;
    background-color: #1e1e2f;
    border-radius: 10px;
    width: 400px;
    border: 1px solid #333;
}

.leftNav h1 {
    font-size: 2.2rem;
    color: #f5f5f5;
    text-align: center;
    margin: 0;
}

.leftNav h1 span {
    color: blue;
}


.diffSection h3 {
    font-size: 1.2rem;
    color: #a0a0b0;
    margin-bottom: 10px;
    text-align: center;
}

.difficulty {
    display: flex;
    justify-content: space-between;
}

.diffBtn {
    flex: 1;
    margin: 0 2px;
    padding: 10px;
    font-size: 0.9rem;
    background-color: #4a4a6a;
    color: #f5f5f5;
}

.diffBtn:first-child {
    margin-left: 0;
}

.diffBtn:last-child {
    margin-right: 0;
}

.diffBtn.active {
    background-color: #007bff;
    box-shadow: 0 0 10px rgba(0, 123, 255, 0.5);
}

.diffBtn:hover:not(.active) {
    background-color: #6a6a8a;
}



.navBtns {

    display: flex;
    flex-direction: column;
    gap: 15px;
    padding: 15px;
    font-size: 1.1rem;
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;

}



.navBtns span {
    font-size: 1.2rem;
}


.navBtns .navNew {
    background-color: #28a745;
}

.navBtns .navNew:hover {
    background-color: #1e7e34;
}

.navBtns .navCustom {

    background-color: rgba(0, 204, 255, 0.941);
}

.navBtns .navCustom:hover {
    background-color: rgb(15, 170, 209);
}

.navBtns .navSolve {
    background-color: blue;
}

.navBtns .navSolve:hover {
    background-color: rgb(9, 9, 213);
}

.navBtns .navClear {
    background-color: #dc3545;

}

.navBtns .navClear:hover {
    background-color: #c61325;
}


/* hint button */
.hint-section {
    text-align: center;
    /* margin-top: 10px;  */
}
.hint-section h3 {
    font-size: 1.2rem;
    color: #a0a0b0;
    margin: 0;
}
.hint-section #hint-count {
    color: #ffffff;

    font-size: 1.3rem;
}


.navBtns .navHint {
    background-color: #ffc107; 
    color: #212529; 
}
.navBtns .navHint:hover {
    background-color: #e0a800; 
}
.hint {
    font-size: 1.1rem;
    background-color: #ffc107f9;
    color: white;
    padding: 8px 10px;
}
.hint:hover {
    background-color: #e0a800;
}

/* save and  load button */
.navBtns .navSave {
    background-color: #6f42c1; 
}
.navBtns .navSave:hover {
    background-color: #5a32a3;
}
.navBtns .navLoad {
    background-color: #fd7e14; 
}
.navBtns .navLoad:hover {
    background-color: #e66a00;
}


.save {
    background-color: #6f42c1;
    color: white;
    padding: 8px 10px;
}
.save:hover { background-color: #5a32a3; }

.load {
    background-color: #fd7e14;
    color: white;
    padding: 8px 10px;
}
.load:hover { background-color: #e66a00; }





@media screen and (max-width:400px) {

    .sudokuBoard input {
        width: 35px;
        height: 35px;
        font-size: 14px;
    }

    .sudokuBoard {
        display: grid;
        grid-template-columns: repeat(9, 35px);
        margin-bottom: 0px;

    }

    .generate {
        padding: 7px 3px;

    }

    .customInput {
        padding: 7px 3px;
    }

    .solve {
        padding: 7px 7px;

    }

    .createBoard {
        padding: 7px 4px;
    }
    .hint {
        padding: 7px 7px;
    }
     .save, .load {
        padding: 7px 5px;
    }


}