单一符号极简主题海报设计

Generate a visual theme poster with a strong graphic sense around any subject: Let the subject content first be refined into a large single symbol or geometric main shape that occupies visual dominance; the main shape lifts slightly from the flat background like thick cardboard or flexible 3D sheets, with edges kept sharp and clean; an extremely thin high-brightness outline appears on one side, and a clear negative space hole or turning gap is left inside, making the first glance perceive huge physical pressure, and the second glance discover it is shaped by same-color layers, shadows, and edge highlights. The background uses an almost impurity-free full-surface theme base color; the main shape and background belong to the same theme color system, layered through differences in lightness, saturation, and shadow depth; colors are extracted from the material, emotion, and information attributes of the theme itself, retaining large areas of high-saturation or high-brightness emotional fields, deep structural shadows, a few clear bright edges, and small areas of information emphasis colors; the overall look should be bright, clean, direct, and ceremonial, avoiding grey/dirty, vintage/yellowed, or smoky treatments. The main shape casts a wide diagonal long shadow to one side, with edges that are soft yet hard, forming a strong sense of direction and presence tension. Text is embedded as information anchors in the whitespace pressure zones next to the main shape, using heavy, compact, and clear sans-serif characters; short sentences are arranged in lines, with font weight competing with the main shape but area restrained; a row of narrow, tall, and evenly spaced auxiliary English or slogans can be placed at the bottom to form a stable closure. Tiny handwritten-style symbols or annotations are allowed as slight contrasts, occupying only a very small area, like immediate marks left by a designer. The overall surface is smooth, the lighting is concentrated, and the boundaries are clean; the composition relies on the huge main shape, negative space holes, long shadows, and restrained text to establish memory points, rather than complex illustrations or decorative stacking.

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Change scene to: A same-color giant shadow countdown poster for the large number 7, continuing to retain the single numerical main shape and negative space hole.
Publishing scenario: A vertical social platform image for course opening or event warm-up.
Text retention: Chinese short phrase reads "开营倒计时", the bottom English slogan is short and restrained.
Dimensions: Landscape 16:9

围绕任意主题对象生成一张强图形感的主题视觉海报：让主题内容先被提炼成一个占据视觉主导的大型单一符号或几何主形，主形像厚纸板或柔性立体片材一样从平整背景中微微抬起，边缘保持锋利干净，一侧出现极细的高明度轮廓亮线，内部留出一个清晰的负形孔洞或转折空隙，使第一眼读到巨大的形体压力，第二眼才发现它由同色层次、阴影和边缘高光塑造。背景使用几乎无杂质的整面主题底色，主形与背景同属一个主题色系，通过明度差、饱和度差和投影深浅分出层级；色彩从主题自身的材质、情绪和信息属性中提取，保留大面积高饱和或高明度的情绪底场、较深的结构阴影、少量清晰亮边和小面积信息强调色，整体要明亮、洁净、直接、有仪式感，避免灰脏、复古泛黄或烟雾化处理。主形向一侧投下宽大的斜向长影，影子边缘柔中带硬，形成强烈的方向感和临场张力。文字作为信息锚点嵌入主形旁的留白压力区，使用粗重、紧凑、清晰的无衬线字，短句分行排列，字重与主形抗衡但面积克制；底部可放一行窄高字距均匀的辅助英文或标语，形成稳定收束。允许加入极小的手写式符号或批注作为轻微反差，只占很小面积，像设计师留下的即时标记。整体表面平滑、光照集中、边界干净，构图依靠巨大主形、负形空洞、长投影和克制文字建立记忆点，而不是依靠复杂插画或装饰堆叠。


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画面换成: 大号数字 7 的同色巨影倒计时海报，继续保留单一数字主形和负形孔洞
发布场景: 课程开营或活动预热用的社交平台竖图
文字保留: 中文短句写“开营倒计时”，底部英文标语简短克制
尺寸: 横版 16:9