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HTML 

              
                <body>
    <h1>Play Tic Tac Toe</h1>
    <div class="spacer"></div>
    <div class="block" id="mode">
        <h1 class="text-center">Choose Player Mode</h1>
        <hr>
        <div class="row text-center">
            <div class="col-sm-6">
                <div class="btn btn-lg btn-default" id="twoplayer">Two Players</div>
            </div>
            <div class="col-sm-6">
                <div class="btn btn-lg btn-default" id="computerplay">Computer Play</div>
            </div>
        </div>
    </div>
    <div class="spacer"></div>
    <div class="block" id="msg">
        <h3>For Computer Play</h3>
        <h3>Player is always "X"</h3>
        <h3>Player always goes first</h3>
        <div class="btn btn-lg btn-default" id="msgbtn">Press to Continue</div>
    </div>
    <div class="spacer"></div>
    <div class="block" id="xo">
        <h1 class="text-center">Choose X or O</h1>
        <hr>
        <div class="row text-center">
            <div class="col-sm-6">
                <div class="btn btn-lg btn-default" id="ex">X</div>
            </div>
            <div class="col-sm-6">
                <div class="btn btn-lg btn-default" id="oh">O</div>
            </div>
        </div>
    </div>
    <div class="spacer"></div>
    <div class="block" id="gmbd">
        <div id="gameboard">
            <div class="row">
                <div class="square bottom right sq1"></div>
                <div class="square bottom right sq2"></div>
                <div class="square bottom sq3"></div>
            </div>
            <div class="row">
                <div class="square bottom right sq4"></div>
                <div class="square bottom right sq5"></div>
                <div class="square bottom sq6"></div>
            </div>
            <div class="row">
                <div class="square right sq7"></div>
                <div class="square right sq8"></div>
                <div class="square sq9"></div>
            </div>
        </div>
        <div class="spacer"></div>
        <div class="btn btn-lg btn-default" id="replay">Replay</div>
    </div>
    
</body>
!

CSS 

              
                body{
    text-align: center;
}

#gameboard{
    width: 364px;
    height: 364px;
    margin: auto;
    margin-left: 51px;
}

.spacer{
    padding: 1%;
  }

.block{
    background-color: rgba(75, 66, 66, 0.8);
    color: white;
    width: 37.5%;
    margin: auto;
    opacity: .75;
    border-radius: 15px;
    font-size: 1.5em;
    padding: 3%;
}

.row{
    clear: both;
    overflow: hidden;
}

.square{
    width: 120px;
    height: 105px;
    float: left;
    cursor: pointer;
    text-align: center;
    font-size: 75px;
    padding-top:15px
}

.bottom{
    border-bottom: 2px solid black;
}

.right{
    border-right: 2px solid black
}
!

JS 

              
                $(document).ready(function(){

    $('#xo').hide();
    $('#gmbd').hide();
    $('#replay').hide();
    $('#msg').hide();

    var player = 1;
    var random = Math.floor(Math.random() * 9) + 1;
    var rand = Math.floor(Math.random() * 9) + 1;
    var tag = ".sq" + rand.toString();

    $('#twoplayer').click(function(){

        $('#mode').hide();
        $('#msg').hide();
        $('#xo').show();

        $('#ex').click(function(){

            $('#mode').hide();
            $('#xo').hide();
            $('#msg').hide();
            $('#gmbd').show();
            $('#replay').show();

            $('.square').on('click', function(event){

                var squareSelected = $(this);
        
                if(squareSelected.hasClass('fa fa-times') || squareSelected.hasClass('fa fa-circle-o')){
                    alert('This square has already been selected. Please select another');
                }
                else{
                    if(player === 1){
                        squareSelected.addClass('fa fa-times');
                        if(checkIfPlayerWon('fa fa-times')){
                            alert('Congratulations! Player ' + player + ' has won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                            
                        }
                        else{
                            player = 2;
                        }
                    }
                    else{
                        squareSelected.addClass('fa fa-circle-o');
                        if(checkIfPlayerWon('fa fa-circle-o')){
                            alert('Congratulations! Player ' + player + ' has won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                        }
                        else{
                            player = 1;
                        }
                    }
                }
        
            });
            
        });

        $('#oh').click(function(){

            $('#mode').hide();
            $('#xo').hide();
            $('#msg').hide();
            $('#gmbd').show();
            $('#replay').show();

            $('.square').on('click', function(event){

                var squareSelected = $(this);
        
                if(squareSelected.hasClass('fa fa-times') || squareSelected.hasClass('fa fa-circle-o')){
                    alert('This square has already been selected. Please select another');
                }
                else{
                    if(player === 1){
                        squareSelected.addClass('fa fa-circle-o');
                        if(checkIfPlayerWon('fa fa-circle-o')){
                            alert('Congratulations! Player ' + player + ' has won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                            
                        }
                        else{
                            player = 2;
                        }
                    }
                    else{
                        squareSelected.addClass('fa fa-times');
                        if(checkIfPlayerWon('fa fa-times')){
                            alert('Congratulations! Player ' + player + ' has won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                        }
                        else{
                            player = 1;
                        }
                    }
                }
        
            });
            
        });

    });

    $('#computerplay').click(function(){

        $('#mode').hide();
        $('#xo').hide();
        $('#gmbd').hide();
        $('#replay').hide();
        $('#msg').show();

        $('#msgbtn').click(function(){

            $('#mode').hide();
            $('#xo').hide();
            $('#msg').hide();
            $('#gmbd').show();
            $('#replay').show();

            $('.square').on('click', function(event){

                var squareSelected = $(this);
        
                if(squareSelected.hasClass('fa fa-times') || squareSelected.hasClass('fa fa-circle-o')){
                    alert('This square has already been selected. Please select another');
                }
                else{
                    if(player === 1){
                        squareSelected.addClass('fa fa-times');
                        if(checkIfPlayerWon('fa fa-times')){
                            alert('Congratulations! Player ' + player + ' has won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                            
                        }
                        else{
                            player = 2;
                        }
                    }
                    else{
                        $(randomSquare(random)).addClass('fa fa-circle-o');
                        if(checkIfPlayerWon('fa fa-circle-o')){
                            alert('Oh no! The Computer won!');
                            $('#replay').click(function(){
                                location.reload(true);
                            });
                        }
                        else{
                            player = 1;
                        }
                    }
                }
        
            });
        
        });

    });

    $('#replay').click(function(){
        location.reload(true);
    });

    function randomSquare(rand){
        while($(tag).hasClass('fa fa-times') || $(tag).hasClass('fa fa-circle-o')){
            rand = Math.floor(Math.random() * 9) + 1;
            tag = ".sq" + rand.toString();
        }
        return tag;
    }

    function checkIfPlayerWon(symbol){

        if($('.sq1').hasClass(symbol) && $('.sq2').hasClass(symbol) && $('.sq3').hasClass(symbol)){
            return true;
        }
        else if($('.sq4').hasClass(symbol) && $('.sq5').hasClass(symbol) && $('.sq6').hasClass(symbol)){
            return true;
        }
        else if($('.sq7').hasClass(symbol) && $('.sq8').hasClass(symbol) && $('.sq9').hasClass(symbol)){
            return true;
        }
        else if($('.sq1').hasClass(symbol) && $('.sq4').hasClass(symbol) && $('.sq7').hasClass(symbol)){
            return true;
        }
        else if($('.sq2').hasClass(symbol) && $('.sq5').hasClass(symbol) && $('.sq8').hasClass(symbol)){
            return true;
        }
        else if($('.sq3').hasClass(symbol) && $('.sq6').hasClass(symbol) && $('.sq9').hasClass(symbol)){
            return true;
        }
        else if($('.sq1').hasClass(symbol) && $('.sq5').hasClass(symbol) && $('.sq9').hasClass(symbol)){
            return true;
        }
        else if($('.sq3').hasClass(symbol) && $('.sq5').hasClass(symbol) && $('.sq7').hasClass(symbol)){
            return true;
        }
        else{
            return false;
        }

    }

});
!
999px

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