Create an original portrait Japanese store discount poster in red, white, and black. Layout: thin red header, large white card with red border, black condition text, huge red amount, angled offer label, and bottom date strip. Text: "店内限定キャンペーン", "店頭で合計2,999円（税込）以上", "お買い上げの方", "その場で", "300円引き!", "期間限定 2026.08.01-2026.08.31". Use two black emphasis rays only; keep the design clean with no ribbons or confetti. Keep all visible text in Japanese. No brand, platform logo, payment logo, watermark, QR code, website, Chinese text, English text, or random tiny text.