I have a question about 'aria-expanded' attritube.

Dear Sir. 
​
Hello, this is hyeyeong from the UI development department at N Technology Services Co.
I'm sending this email to ask a question about 'aria-expanded' attribute.
​
I am developing this UI.
--> https://codepen.io/spiyer/pen/qYOeWg
​
This UI can be explained as follows.
The body area(.section_a_body) is expanded or collapsed when the user presses the +/- button.
Additionally, I provided invisible text 'Add module' for screen reader users.
​
My question is that I dont' know where to put 'aria-expanded' attribute.
​
1. <section class="section_a">
2. <div class="togglebutton">
3. <div class="section_a_body">
4. Do not put. (because this UI is made by using input checkbox.)
5. Other advices....
​
I have already confirmed WAI-ARIA-1.1 documentation, but I'm not sure about it.​
​ 
I'm looking forward to hearing from you.
Thank you.
​
Sincerely,
Hyeyeong Jeon
​
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전혜영 HYEYEONG JEON
UI개발4팀

경기도 성남시 분당구 황새울로 359번길 11 미래에셋플레이스, 13590
Mobile 010-2244-2948
Email h.y.jeon@nhn.com

Received on Monday, 23 April 2018 09:22:19 UTC