css - 过渡不适用于图像

Question

HTML

  <div id="wrapper">
   <a href="myfile.htm"> <img  id="kohv"  src="Alumine valik\kohv.jpg" /></a>
    <a href="myfile.htm"><img  id="tee"  src="Alumine valik\kann.jpg" /> </a>   
    <a href="myfile.htm"><img  id="kakao"  src="Alumine valik\kakao.jpg" /> </a>   
    <a href="myfile.htm"><img  id="masinad"  src="Alumine valik\Masinad.jpg" </a>    
    <a href="myfile.htm"><img  id="hooldus"  src="Alumine valik\wrench.jpg" />  </a>    
</div>

CSS

#kohv { 
        float:left;
        width:100px;
        margin-top:350px;
        height:100px;
        position:relative;
  -webkit-transition: all 1s ease;
  -moz-transition: all 1s ease;
  -o-transition: all 1s ease;
  transition: all 1s ease;
    }
    #kohv:hover{ 
         top: -10px;
         padding-bottom:15px;

    }

我的悬停效果不会添加过渡，有什么解决方案吗？我尝试了我所知道的一切，我尝试了它的多种变体，尝试了谷歌。我真的很想知道我的代码有什么问题。