css - Change state but don't change style Reactjs -

it's weird when try change style of section changing state when user mouseover button. content of h1 tag changed style of section isn't. me on that?

    export class jumbotron extends component {      constructor (props) {     super(props)     this.state = {       style: {         backgroundimage: 'none'       }     }      this.handlesubjectmouseover = this.handlesubjectmouseover.bind(this)   }    handlesubjectmouseover (bg) {     console.log(bg)     this.setstate({       style: {         backgroundimage: bg       }     })   }    render () {     return <section classname="jumbotron container" style=     {this.state.style}>       <h1>{this.state.style}</h1>       <div classname="jumbotron-content">         <h2 style={{marginbottom: 3, margintop: 40}}>learning fun          live</h2>         <div style={{marginleft: 10}}>body ........</div>         <div style={{marginbottom: 20, margintop: 80}}              classname="subjects-title">top classes, tutorial & tips excel in:         </div>         <div classname="subjects" style={{backgroundimage: this.state.background}}>           <raisedbutton label="math" secondary onmousemove={() => { this.handlesubjectmouseover(mathbg) }} />           <raisedbutton label="physics" secondary onmousemove={() => { this.handlesubjectmouseover(physicbg) }} />           <raisedbutton label="chemistry" secondary onmousemove={() => { this.handlesubjectmouseover(chemistrybg) }} />           <raisedbutton label="biology" secondary onmousemove={() => { this.handlesubjectmouseover(biologybg) }} />           <raisedbutton label="comp science" secondary                         onmousemove={() => { this.handlesubjectmouseover(computerbg) }} />         </div>       </div>     </section>   } 

use following line in place of setting background image

style={{'backgroundimage': 'url('+this.state.background+')'}} 

to read more in details here & here.

and check css-loader issues webpack here.

hopes you!