复古正式风格古典装饰艺术特征蓝白配色典雅证书插画

illustration, minimalistic style, light blue and white color scheme, fresh and elegant palette, certificate template centered, decorative geometric pattern border, watermark texture, text includes 'CERTIFICATE', 'PLACE FOR YOUR TEXT', Latin sample text, signature 'John Smith', background with subtle paper texture, formal and professional visual effect, conveys authority and official information