LinearGradient

<svg>
  <defs>
        <linearGradient id='g' y1="100%" x2="100%">
            <stop offset='0%' stop-color='yellow' />
            <stop offset='100%' stop-color='green' />
        </linearGradient>
    </defs>
    <rect width='100%' height='100%' fill='url(#g)'/>
</svg>