A simple example of auto-resize using svg viewBox.

viewbox.js

var svg = d3.select('#container').append('svg')
.attr({
  viewBox: '0 0 1000 1000',
});

svg.append('rect')
.attr({
  width: '1000',
  height: '1000'
});

svg.append('rect')
.attr({
  width: '100',
  height: '100',
  fill: 'red'
});