A computer-implemented method includes displaying multiple content items in a user interface, where each content item has an initial time value. Input is received to modify time values of the multiple content items. Input of a new time value for a content item of the multiple content items is also received. A change amount value is determined based on the difference between an initial time value of the content item and the new time value. For each content item, the initial time value is modified to a different time value by applying the change amount value to the initial time value.