.VisiCalcClass {
  background:url(/staticAssets/calculators/load.gif) 50% 15% no-repeat;
  background-size: 150px 150px;
  min-width: 800px;
  min-height:800px;
  margin:0;
  padding:0;
}

#Loan_Repayment_Calculator { min-height:800px !important; } 

<iframe class="VisiCalcClass" id="Loan_Repayment_Calculator" src=" https://www.visionabacus.net/Tools/B3/SuiteA/Z200/MFAA/Loan_Repayment_Calculator/BlueOrange" frameborder="0" scrolling="yes"></iframe>

 @BohoBabe