Mimicking a perfect example WP theme basic styles.

example-theme-basic-styles.css

/**
 * Colors.
 */

	body {
		background: #222;
		color: #ccc;
	}

	h1, h2, h3, h4, h5, h6 {
		color: #fff;
	}

	a,
	a:hover,
	a:focus,
	a:active,
	a:visited {
		color: #f00;
	}

/** 
 * Typography.
 */

	html {
		line-height: 1.62;
		font-family: Georgia, serif;
	}

	@media (min-width: 60em) {
		html {
			font-size: 1.125em;
		}
	}

	h1, h2, h3, h4 {
		font-weight: 900;
		letter-spacing: .025em;
	}

	h1 {
		font-size: 2.058em;
		line-height: 1.19;
		margin-top: 1.17152em;
		margin-bottom: 0.66149em;
	}

	h2 {
		font-size: 1.618em;
		line-height: 1.38;
		margin-top: .62247em;
		margin-bottom: .72553em;
	}

	h3, h4 {
		font-size: 1.382em;
		line-height: 1.38;
		margin-top: .62247em;
		margin-bottom: .72553em;
	}

	@media (min-width: 60em) {
		h1 {
			font-size: 2.618em;
			line-height: 1.19;
			margin-top: .66638em;
			margin-bottom: .51999em;
		}

		h2 {
			font-size: 2.058em;
			line-height: 1.19;
			margin-top: 1.17152em;
			margin-bottom: 0.66149em;
		}

		h3, h4 {
			font-size: 1.618em;
			line-height: 1.38;
			margin-top: .62247em;
			margin-bottom: .72553em;
		}
	}