Generate a vertical 9:16 Father's Day themed poster, with the theme "【main title】". The background is 【seasonal atmosphere】, the overall palette is 【main color 1】, 【main color 2】, 【accent color】, with soft-focus light, an airy feel, light grain and refined white space. The image should feel warm, quiet, companionable and nostalgic, not a cheap festival-promo style. The main subject is a silhouette interaction scene of a father and child: 【specific action, e.g. father holding the child's hand while walking / father pushing the child's bicycle / father carrying the child on his back / father tying the child's shoelaces】. The figures are shown only as outlines, no facial features, emphasizing fatherly love, companionship, protection and growth. Complete layout: A large handwritten Chinese title at the top "【main title】". Next to the title, small English "Father's Day". On the left, a short vertical Chinese phrase "【vertical copy】". In the central white space, an emotional line: "【main copy】". At the bottom, a large English serif title "HAPPY FATHER'S DAY". At the base, the date "06/21" and small Chinese "父亲节快乐". Overall style: Father's Day poster, parent-child silhouette, summer light, soft-focus photography, solar-term poster, refined magazine layout, warm and healing, low-saturation colors, oriental white space. Requirements: Chinese text clear and accurate, no garbled characters, no logo, no watermark, no QR code, no cartoon, no promo-template feel.