fix(script error): fix unexpected token

[cntanglijun]

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Description

升级 hexo 4.1.0 之后的版本，出现脚本错误的情况。由于 hexo 更新了 css() 方法 #3690，会在结果前后添加 \n 字符，所以这里使用 .trim() 方法做一下处理

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