Whiteboard Explainer Segment

Clean modern 2D animated explainer style, 16:9, flat-friendly palette (navy, teal, coral, warm gray), soft rounded line art with subtle texture, friendly geometric characters. Topic segment: "How a vaccine trains your immune system." Sequence with smooth 8-second beats: (1) a friendly simplified human outline appears with an immune-system shield badge; (2) a train-car of weakened vaccine antigens (drawn as small non-scary geometric shapes with flags) enters a station mapped to the body; (3) B-cell factory workers read the flag blueprints and build Y-shaped antibody keys on a conveyor; (4) the keys are filed in a labeled memory cabinet; (5) later, real virus shapes approach and are instantly recognized and captured by the stored keys; shield badge glows with a check. Gentle continuous morphing transitions, bouncy easing, clear empty space top and bottom for captions, approachable non-medical anxiety tone, light xylophone-and-clicks sound design, no text within the animation (captions added later), accurate high- level biology, 24fps, character consistency across beats. ================================================================================