<span data-bind="style: {color: priceColor, fontWeight: priceFontWeight},text: price"></span> 
 
<script> 
var viewModel = kendo.observable({ 
    price: 42, 
    priceColor: function() { 
        var price = this.get("price"); 
 
        if (price <= 42) { 
            return "#00ff00"; 
        } else { 
            return "#ff0000"; 
        } 
    }, 
    priceFontWeight: function() { 
        var price = this.get("price"); 
 
        if (price <= 42) { 
            return "bold"; 
        } else { 
            return ""; //will reset the font weight to its default value 
        } 
    } 
}); 
 
kendo.bind($("span"), viewModel); 
</script>