How to align treegrid columns

Question

Even though each of my columns is set at a fixed pixel width, my treegrid columns are all over the place (i.e. not aligning in a straight line). Please see screenshot which illustrates issue. Also, below is an overview of the code for the treegrid. Any ideas on how to fix this issue?

var currentdate = new Date();

var currenthour = currentdate.format('G');
var intcurrenthour = parseInt(currenthour);
intcurrenthour = intcurrenthour + 1; 

var currentday = currentdate.format('D M j Y'); 
var basecolor = "#FFFFFF";
var currentcolor = "#F0F0F0";
var i = 0;
var x;

function fn(v, values){

    if(i == 3){i = 0}

    i = i + 1;

    switch(i){
        case 1: x = values.alarm1; break;
        case 2: x = values.alarm2; break;
        case 3: x = values.alarm3; break;

        default: alert("x not assigned value");
    }

    if (x == 1) {return '<span style="background-color: red; width: 100%">' + v + '</span>';}
    else if(i == intcurrenthour)
        {return '<span style="background-color:' + currentcolor + '; width: 100%">' + v + '</span>';}
        else
        {return '<span style="background-color:' + basecolor + '; width: 100%">' + v + '</span>';}  
    }

var TDCurrentDay = new Ext.ux.tree.TreeGrid({
            title: currentday,
            requestMethod : 'GET',
        margins: '5 5 0 5',
        height: 400,
        collapsible:false,
        region:'center',
        autowidth: false,
        headersDisabled: true,
        viewConfig:{forceFit:true},
        tbar: {
            xtype: 'toolbar',
            items: [
                {xtype: 'button',text: 'Expand All', icon:'../images/expand-all.gif',
                    handler: function(){
                        TDCurrentDay.expandAll();
                    }
                },
                {xtype: 'spacer',width:5},
                {xtype: 'button',text: 'Collapse All', icon:'../images/collapse-all.gif',
                    handler: function(){
                        TDCurrentDay.collapseAll();
                    }
                }
            ]
        },
        enableDD: false,
        columns:[
            {header: 'Unit',dataIndex: 'unit', width: 210},

            {header: 'H1', width: 60, dataIndex: 'duration1', align: 'center',              
                tpl: new Ext.XTemplate('{duration1:this.doFormat}', {
                    doFormat: fn     
                })
            },

            {header: 'A1', width: 0,dataIndex: 'alarm1', visibility: false},

            {header: 'H2', width: 60, dataIndex: 'duration2', align: 'center',
                    tpl: new Ext.XTemplate('{duration2:this.doFormat}', {
                        doFormat: fn     
                            })
            },

            {header: 'A2', width: 0,dataIndex: 'alarm2', visibility: false},


            {header: 'H3', width: 60, dataIndex: 'duration3', align: 'center',
                    tpl: new Ext.XTemplate('{duration3:this.doFormat}', {
                        doFormat: fn     
                            })
            },

            {header: 'A3', width: 0,dataIndex: 'alarm3', visibility: false}

        ],

            dataUrl: 'treegrid-data.json'
});

Answer 1

With some great help from Sencha Support, fixed the issue by removing the treegrid.css file which for some reason was causing the column alignment issue and added the below code for the cell borders:

.x-treegrid-col {
    border: 1px solid #efefef;
}