Use flexbox to position modals (not blurry anymore), set min-height for header, closes #1528
Use flexbox to position modals (not blurry anymore), set min-height for header, closes #1528

leafo/itchio-app,itchio/itch,itchio/itch,itchio/itchio-app,itchio/itchio-app,itchio/itchio-app,itchio/itch,itchio/itch,leafo/itchio-app,itchio/itch,itchio/itch,leafo/itchio-app