How can I remove shadow from expansion panel (Vuetify)?

With Veutify 2 the following css does the job.

.v-expansion-panel::before {
   box-shadow: none !important;

You can set elevation-0 class on v-expansion-panel.

Here is working example:

I'd rather avoid changing CSS, because it will remove all borders and shadows, on all expansion panels on all pages.

In Vuetify v.2 you can use the attribute flat in v-expansion-panels. Documented here:

<v-expansion-panels flat>
    <v-expansion-panel >