Kendo dropDownList doesn't work with then Chart on the page

[Sharif]

I have simple chart on the page. I added dropdownlist to filter the chart. I chrome the dropdown won't expand. In IE 10.  the dropdown will expand only if I click on the text only. I copied the example form the demo and pasted on the same page and it didn't work. when I removed the chart it worked fine.
   
@(Html.Kendo().DropDownList()
.Name("color")
.DataTextField("Text")
.DataValueField("Value")
.Events(e => e.Change("change"))
.BindTo(new List<SelectListItem>() {
new SelectListItem() {
Text = "Black",
Value = "1"
},
new SelectListItem() {
Text = "Orange",
Value = "2"
},
new SelectListItem() {
Text = "Grey",
Value = "3"
}
})
.Value("1")
)

[Sharif]

I found I need to put spacer between the dropdown list and the chart-wrapper

<div class"ddl"/>
<div class="spacer"/>
<div class="chart-wrapper"/>