Internet Explorer中的问题，定位？

Question

Everything works fine in all other browsers than Internet Explorer, suprise! The blue triangle is supposed to be on top of the box using position absolute/relative. And as i said it works but looks like in the picture in Internet explorer. Does anyone know thats causing this??? :)

<div class="services">
    <a href="#"> 
        <div class="box redovisning">
            <img class="boxImage" src="../img/accounting_icon.svg" alt="redovisning.png">
            <h3>redovisning</h3>
            <div class="triangle-bottomright"></div>
        </div>
    </a>
    <a href="#"> 
        <div class="box consulting">
            <img src="../img/consulting_icon.svg" alt="consultation.png">
            <h3>rådgivning</h3>
            <div class="triangle-bottomright"></div>
        </div>
    </a>
    <a href="#"> 
        <div class="box revision"> 
            <img class="boxImage" src="../img/revision_icon.svg" alt="revision.png">
            <h3>revision</h3>
            <div class="triangle-bottomright"></div>
        </div>
    </a>
</div>


CSS:
.services {
    width:100%; 
    display: flex; 
    flex-direction: row; 
    justify-content: space-around; 
    flex-wrap:wrap; 
    margin-bottom:40px; 
}
.box {
    position: relative;
    height:300px; 
    width:300px; 
    border: 2px solid $black;  
    display:flex; 
    justify-content:center; 
    flex-direction:column; 
}
.box:hover > .triangle-bottomright {
    border-left: 0 solid transparent;
    right: 0;
}
.box:hover > h3 {
    color:$black; 
}
.consulting img {
    width: 80%;
    height: 211px;
}
.triangle-bottomright {
    transition: all .3s ease-in-out;
    width: 0;
    height: 0;
    right: 0;
    border-bottom: 300px solid $blue;
    border-left: 298px solid transparent;
    z-index: 1; 
    position:absolute; 
}

Answer 1

It seems that IE expects you to give it the top value also for an element with absolute positioning. This should solve your problem:

.triangle-bottomright {
  transition: all .3s ease-in-out;
  width: 0;
  height: 0;
  right: 0;
  top: 0;
  border-bottom: 300px solid $blue;
  border-left: 298px solid transparent;
  z-index: 1; 
  position:absolute; 
}