Elegant Tropical Botanical Watercolor Banner

minimal botanical watercolor banner, pale green tropical palm fronds and narrow leaves hanging down from the top edge, overlapping layered foliage forming a soft natural border, large clean white negative space below for text, faint hint of greenery along the bottom edge, delicate translucent watercolor washes, hand-painted paper texture, airy composition, soft diffused daylight, fresh sage green and olive tones, elegant tropical stationery design, no text, no objects in center