Similar to line, shapes should be used in moderation if we are to avoid visual friction and the "box-within-box" aesthetic.

与线相似，形状的使用应适度，我们要尽量避免视觉不谐感和“框中有框”的设计。

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Customers were signing up briskly, but Levie felt there was still too much friction in the act of pulling out a credit card to open a Box account.

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