To generate an image depicting a heart with a sinus rhythm, calm and steady, in the center of the composition. I want the heart to be surrounded by human figures shouting and waving their arms, while the heart remains still and calm. The goal is to highlight the contrast between the serenity of the heart and the agitation of the surrounding figures. Make sure that the heart is the focal point of the image and that the characters' expressions and gestures accentuate the visual contrast. Use colors that emphasize this contrast and clearly communicate the theme of inner calm in the face of outer turbulence.