/* Keep these responsive exercises inside the textbook's reading column. */
#DerivationPRO iframe.embeddedExercise,
#DerivationPalindromePRO iframe.embeddedExercise,
#DerivationLeftmostPRO iframe.embeddedExercise {
  width: 100% !important;
  max-width: 100% !important;
  box-sizing: border-box;
}