ipsos-components/src/material-examples/expansion-steps/expansion-steps-example.css

Material Design components for Angular

.example-headers-align .mat-expansion-panel-header-title, 
.example-headers-align .mat-expansion-panel-header-description {
  flex-basis: 0;
}

.example-headers-align .mat-expansion-panel-header-description {
  justify-content: space-between;
  align-items: center;
}