.MuiAccordion-root { position: relative; transition: margin 150ms cubic-bezier(0.4, 0, 0.2, 1) 0ms; } .MuiAccordion-root:before { top: -1px; left: 0; right: 0; height: 1px; content: ""; opacity: 1; position: absolute; transition: opacity 150ms cubic-bezier(0.4, 0, 0.2, 1) 0ms,background-color 150ms cubic-bezier(0.4, 0, 0.2, 1) 0ms; background-color: rgba(0, 0, 0, 0.12); } .MuiAccordion-root.Mui-expanded { margin: 16px 0; } .MuiAccordion-root.Mui-disabled { background-color: rgba(0, 0, 0, 0.12); } .MuiAccordion-root.Mui-expanded + .MuiAccordion-root:before { display: none; } .MuiAccordion-root.Mui-expanded:first-child { margin-top: 0; } .MuiAccordion-root.Mui-expanded:last-child { margin-bottom: 0; } .MuiAccordion-root.Mui-expanded:before { opacity: 0; } .MuiAccordion-root:first-child:before { display: none; } .MuiAccordion-rounded { border-radius: 0; } .MuiAccordion-rounded:first-child { border-top-left-radius: 4px; border-top-right-radius: 4px; } .MuiAccordion-rounded:last-child { border-bottom-left-radius: 4px; border-bottom-right-radius: 4px; } @supports (-ms-ime-align: auto) { .MuiAccordion-rounded:last-child { border-bottom-left-radius: 0; border-bottom-right-radius: 0; } }