Scroll to href atribute link like href="#targetID"

scroll_to.js

// DEMO: https://jsfiddle.net/onigetoc/5kh0e5f4/
function ScrollTo(target, speed, timeout, margin) {

  if (!timeout) timeout = 0;
  if (!speed) speed = 1000;
  if (!margin) margin = 0;

  if (typeof target !== "undefined") {
    setTimeout(function() {
      $('html,body').animate({
        scrollTop: $(target).offset().top - margin
      }, speed);
    }, timeout);
  }
}

//////////////// END SCROLL TO FUNCTION  /////////////////////
// USAGE:
// Check if link begin with # HASH or . DOT
// for example it will automatically scroll to comments
$('a[href^="#"], a[href^="."]').click(function(e) {
    e.preventDefault();
    ScrollTo($(this).attr("href"), 500,0,10);  //target, speed, timeout, margin
});
// OR USUAL JQUERY .CLICK WITH TARGET
/*
$("#link-li a").click(function(e) {
  // Prevent a page reload when a link is pressed
  e.preventDefault();
  // Call the scroll function
  ScrollTo($(this).attr("href"), 500,0,100);  //target, speed, timeout, margin
  //ScrollTo( "#about", 500,0,100 );  //target, speed, timeout, margin
});
*/

zdemo.html

<div id="container">
  <div id="link-li">
    <ul>
      <li><a id="aboutlink" href="#about">About (ID)</a>

      </li>
      <li><a id="projectslink" href="#projects">Projects (ID)</a>

      </li>
      <li><a id="resumelink" href="#resume">Resume (ID)</a>

      </li>
      <li><a id="contactlink" href=".contact">Contact (Class)</a>

      </li>
    </ul>
  </div>
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    <div class="" id="about">
      <p class="header">About</p>
      <p class="info">Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure
        dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
    </div>
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  <div id="content">
    <div class="sections" id="projects">
      <p class="header">Projects</p>
      <p class="info">Infos Projects</p>
    </div>
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    <div class="sections" id="resume">
      <p class="header">Resume</p>
      <p class="info">Infos Resume</p>
    </div>
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    <div class="sections contact" id="contactID">
      <p class="header">Contact</p>
      <p class="info">Infos Contact</p>
    </div>
  </div>
</div>
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