The unit length is 20px.

Three 'inline-block'. Red 'inline-block' goes from 'margin-left: 0 ~ -80px'.

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Same as above. Stop temporarily at 'margin-left: -20px' (when the outer size is zero) and at 'margin-left: -40px'.

我我我我我我

Red 'inline-block' goes from 'margin-right: 0 ~ -80px'..

我我我我我我

Same as above. Stop temporarily at 'margin-right: -20px' (when the outer size is zero) and at 'margin-right: -40px'.

我我我我我我