updated readme

Author: tyrneh

README.md

@@ -21,8 +21,8 @@
    - Fitting a vol surface well is a complex and expensive process, with the leading software provider costing $50k USD/month/seat. OIPD open-sources the entire pipeline fairly rigorously, with further improvements in the roadmap.
 
 <p align="center" style="margin-top: 80px;">
-  <img src=".meta/images/vol_curve.png" alt="vol curve" style="width:49%; height:auto; display:inline-block; margin-top:50px;" />
-  <img src=".meta/images/vol_surface.png" alt="placeholder" style="width:49%; height:auto; display:inline-block; margin-top:50px;" />
+  <img src=".meta/images/vol_curve.png" alt="vol curve" style="width:49%; height:320px; object-fit:cover; display:inline-block; margin-top:50px; border:1px solid #000;" />
+  <img src=".meta/images/vol_surface.png" alt="vol surface" style="width:49%; height:320px; object-fit:cover; display:inline-block; margin-top:50px; border:1px solid #000;" />
 </p>