﴿ مُّتَّكِـِٔينَ فِيهَا عَلَى ٱلْأَرَآئِكِ ۖ لَا يَرَوْنَ فِيهَا شَمْسًۭا وَلَا زَمْهَرِيرًۭا ﴾

“In that [garden] they will on couches recline, and will know therein neither [burning] sun nor cold severe,”

reclining muttaki’īna is a circumstantial qualifier referring to the subject of the implicit verb udkhilūhā ‘they are admitted into it’ therein upon couches arā’ik are beds inside canopies. They will not find lā yarawna is a second circumstantial qualifier therein either sun or bitter cold neither heat nor cold; but it is also said that zamharīr means ‘the moon’ and so in other words it means that it will be bright without any sun or moon.