<p>Changes the form control's <a href=#concept-fe-value title=concept-fe-value>value</a> by the value given in the
<code title=attr-input-step><a href=#attr-input-step>step</a></code> attribute, multiplied by
<var title="">n</var>.</p>
<var title="">n</var>. The default is 1.</p>
<p>Throws <code><a href=#invalid_state_err>INVALID_STATE_ERR</a></code> exception if the control
is neither date- or time-based nor numeric, if the <code title=attr-input-step><a href=#attr-input-step>step</a></code> attribute's value is "<code title="">any</code>", if the current <a href=#concept-fe-value title=concept-fe-value>value</a> could not be parsed, or if
these steps; otherwise, let <var title="">value</var> be the result
of that algorithm.</li>
<li><p>Let <var title="">n</var> be the argument, or 1 if the
argument was omitted.</li>
<li><p>Let <var title="">delta</var> be the <a href=#concept-input-step title=concept-input-step>allowed value step</a> multiplied by
<p>Changes the form control's <a href=#concept-fe-value title=concept-fe-value>value</a> by the value given in the
<code title=attr-input-step><a href=#attr-input-step>step</a></code> attribute, multiplied by
<var title="">n</var>.</p>
<var title="">n</var>. The default is 1.</p>
<p>Throws <code><a href=#invalid_state_err>INVALID_STATE_ERR</a></code> exception if the control
is neither date- or time-based nor numeric, if the <code title=attr-input-step><a href=#attr-input-step>step</a></code> attribute's value is "<code title="">any</code>", if the current <a href=#concept-fe-value title=concept-fe-value>value</a> could not be parsed, or if
these steps; otherwise, let <var title="">value</var> be the result
of that algorithm.</li>
<li><p>Let <var title="">n</var> be the argument, or 1 if the
argument was omitted.</li>
<li><p>Let <var title="">delta</var> be the <a href=#concept-input-step title=concept-input-step>allowed value step</a> multiplied by