Generate an SVG as a thank-you greeting card illustration. Warm watercolor style. Draw a sunflower bouquet at lower-center — 3 sunflower shapes (petal ring in #FBBF24, dark center circle) with green leaf paths, tied with a ribbon bow in #F97316. Add soft golden ray shapes radiating behind the bouquet (opacity 0.3). Scatter small star and petal shapes in golden yellow. Warm gratitude glow. No text, no labels, no emoji. Output raw SVG code only starting with <svg.

The image shows a thank you card with a bouquet of sunflowers and the words "Thank You" written in a bold font. The card is decorated with a vibrant array of yellow and orange flowers, and the text is surrounded by a white border.