Preview:
.CodeMirror {
	.cm-heading {
		font-weight: normal;
	}

	.cm-heading[cm-level="1"] {
		font-style: normal;
		font-weight: bold;
		line-height: @lineHeight * 1.5;
	}

	.cm-heading[cm-level="2"] {
		font-style: normal;
		font-weight: bold;
		color: #0F80FF;
	}
	.cm-heading[cm-level="3"] {
		font-style: italic;
		font-weight: bold;
		color: #CE2D53;
	}
	.cm-heading[cm-level="4"] {
		font-style: normal;
		font-weight: bold;
		color: #B3B3B3;
	}
}
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