Remove overriding styles over Algolia theme of instantsearch.css
Why
Algolia's theme in https://www.npmjs.com/package/instantsearch.css/v/7.4.4, which is currently used in the site, perfectly implemented them with negative margins: https://github.com/algolia/instantsearch-specs/blob/v7.4.4/src/scss/themes/algolia.scss#L277-L305, so we do not need to override part of them.
What
Removes styles overriding over Algolia theme of instantsearch.css. These styles were mistakenly introduced in !1096 (merged)
Closes #936 (closed)
Edited by Takuya Noguchi