Basic fluid grid HTML
Make any row "fluid" by changing .row to .row. The column classes stay the exact same, making it easy to flip between fixed and fluid grids.
<div class="row">  <div class="col-md-4">...</div>  <div class="col-md-8">...</div></div>
Fluid offsetting
Operates the same way as the fixed grid system offsetting: add .offset* to any column to offset by that many columns.
<div class="row">  <div class="col-md-4">...</div>  <div class="col-md-4 offset2">...</div></div>
Fluid nesting
Fluid grids utilize nesting differently: each nested level of columns should add up to 12 columns. This is because the fluid grid uses percentages, not pixels, for setting widths.
<div class="row">  <div class="col-md-12">    Fluid 12    <div class="row">      <div class="col-md-6">        Fluid 6        <div class="row">          <div class="col-md-6">Fluid 6</div>          <div class="col-md-6">Fluid 6</div>        </div>      </div>      <div class="col-md-6">Fluid 6</div>    </div>  </div></div>
About responsive Bootstrap

Media queries allow for custom CSS based on a number of conditions—ratios, widths, display type, etc—but usually focuses around min-width and max-width.
    - Modify the width of column in our grid
- Stack elements instead of float wherever necessary
- Resize headings and text to be more appropriate for devices
Use media queries responsibly and only as a start to your mobile audiences. For larger projects, do consider dedicated code bases and not layers of media queries.