Dua Lipa Goes for a Boob Tan in the Hot Miami Sun

Dua Lipa’s been tearing up the stage on her "Radical Optimism" tour ... but even pop queens need a breather, and she grabbed hers before lighting up Miami!

Check it out -- Dua flaunted her insanely toned, bronzed bod in a teeny metallic bikini at The Setai Miami Beach on Thursday, even tugging the strings down while lounging to dodge those dreaded tan lines.

Dua kept it makeup-free and low-key -- scrolling her phone, chatting with a pal, and soaking up chill vibes as she recharged.

The Brit was clearly soaking up every spare second of downtime -- with back-to-back Miami shows tonight and Saturday.