feat: add dropdown component

inertia/components/common/dropdown/dropdown_container.tsx

@@ -0,0 +1,17 @@
+import styled from '@emotion/styled';
+
+const DropdownContainer = styled.div<{ show: boolean }>(({ show, theme }) => ({
+  position: 'absolute',
+  top: 'calc(100% + 0.5em)',
+  right: 0,
+  minWidth: '175px',
+  backgroundColor: show ? theme.colors.secondary : theme.colors.background,
+  border: `2px solid ${theme.colors.secondary}`,
+  borderRadius: theme.border.radius,
+  boxShadow: theme.colors.boxShadow,
+  display: show ? 'flex' : 'none',
+  flexDirection: 'column',
+  overflow: 'hidden',
+}));
+
+export default DropdownContainer;