how to change is background color of selected item in list in react js

Question

only selected item have change the background color of list, please help to how to change the background color of specific element in this list items

 <div style={{ padding: '0px 28px', marginBottom: '20px' }}>
               <div className='date__container'>
                  {arrdays.map((dayy, id) => (
                     <TimeContainer
                        day={dayy.day}
                        date={dayy.date}
                       
                     />
                  ))}
               </div>
            </div>

TimeContainer component

const TimeContainer = (props) => {
      const month = ['January','February','March','April','May','June','July','August','September','October','November','December'];

      
      return (
         <div
            className='dateBox'
           
            style={{
               backgroundColor: `${props.isSelected===props.key ? 'purple' : 'white'}`,
            }}
         >
            <p style={{ fontSize: '16px', color: '#888', fontWeight: 'bold' }}>
               {props.day}
            </p>
            <p style={{ color: 'black', fontSize: '17px', fontWeight: 'bold' }}>
               {props.date}
            </p>
         </div>
      );
   };