How can WeChat Mini Programs set the font size of the root element and then use rem?

@ media only screen and (min-width:320px) {html {font-size:12px;}}
@ media only screen and (min-width:375px) {html {font-size:13px;}}
@ media only screen and (min-width:412px) {html {font-size:14px;}}

htmlrem1rembodypagepage1rem1rem16px1rem

reset css uses rpx as a unit

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b30d5a-2bd39.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b30d5a-2bd39.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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