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Center content through flexbox
/* ==UserStyle==
@name center-content
@author zhengqunkoo
@description Center content through flexbox
@version 1.1
@match <all_urls>
@excludeMatches file:///*
@excludeMatches https://duckduckgo.com/*
@excludeMatches https://console.cloud.google.com/*
@run-at document-start
@namespace https://greasyfork.org/users/673982
==/UserStyle== */
html {
display: flex;
justify-content: center;
}