Choose the gradient Tool (g) and with a black, white linear gradient drag from down to top.

选择渐变工具，选择黑-白线性渐变，从下往上拖动(下图中红线所示，从下往上拖动)。

youdao

She decided to start picking up the house from the top down.

她决定开始彻底收拾那房子。

《柯林斯英汉双解大词典》

The robin flew down from his tree-top and hopped about or flew after her from one bush to another.

知更鸟从他的树梢上飞下来，在她身后跳来跳去，或从一个灌木丛飞到另一个灌木丛。

youdao

There was a new effort to build wealth from the bottom up, rather than from the top down.

VOA: special.2011.03.24

"We're meeting with people from IOC members all the way down to volunteers, including USOC,VANOC, sponsors from the top level to the national level,to suppliers."

VOA: standard.2010.02.26

Since games are being built to scale down from the top-end (which means PCs) down to the low-end (smartphones) consoles are stuck in the middle and not able to move the industry from a technical standpoint.

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While featuring the same keyboard arrangement and operating style made popular by previous ClassPad calculators, the fx-CP400 is also fitted with keys that slope down from bottom to top, which helps prevent input errors when pressing vertically arranged keys.

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These plans are usually offered to all employees at a company, from top executives down to the custodial staff.

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