Ищите в данном скрипте - http://diditen.kz/js/plugins.js следующий участок кода:
// SmoothScroll for websites v1.2.1
// Licensed under the terms of the MIT license.
// People involved
// - Balazs Galambosi (maintainer)
// - Michael Herf (Pulse Algorithm)
;!function(){function e(){var e=!1;e&&c("keydown",r),v.keyboardSupport&&!e&&u("keydown",r)}function t(){if(document.body){var t=document.body,n=document.documentElement,o=window.innerHeight,r=t.scrollHeight;if(S=document.compatMode.indexOf("CSS")>=0?n:t,w=t,e(),x=!0,top!=self)y=!0;else if(r>o&&(t.offsetHeight<=o||n.offsetHeight<=o)){var a=!1,i=function(){a||n.scrollHeight==document.height||(a=!0,setTimeout(function(){n.style.height=document.height+"px",a=!1},500))};if(n.style.height="auto",setTimeout(i,10),S.offsetHeight<=o){var l=document.createElement("div");l.style.clear="both",t.appendChild(l)}}v.fixedBackground||b||(t.style.backgroundAttachment="scroll",n.style.backgroundAttachment="scroll")}}function n(e,t,n,o){if(o||(o=1e3),d(t,n),1!=v.accelerationMax){var r=+new Date,a=r-C;if(a<v.accelerationDelta){var i=(1+30/a)/2;i>1&&(i=Math.min(i,v.accelerationMax),t*=i,n*=i)}C=+new Date}if(M.push({x:t,y:n,lastX:0>t?.99:-.99,lastY:0>n?.99:-.99,start:+new Date}),!T){var l=e===document.body,u=function(){for(var r=+new Date,a=0,i=0,c=0;c<M.length;c++){var s=M[c],d=r-s.start,f=d>=v.animationTime,h=f?1:d/v.animationTime;v.pulseAlgorithm&&(h=p(h));var m=s.x*h-s.lastX>>0,w=s.y*h-s.lastY>>0;a+=m,i+=w,s.lastX+=m,s.lastY+=w,f&&(M.splice(c,1),c--)}l?window.scrollBy(a,i):(a&&(e.scrollLeft+=a),i&&(e.scrollTop+=i)),t||n||(M=[]),M.length?N(u,e,o/v.frameRate+1):T=!1};N(u,e,0),T=!0}}function o(e){x||t();var o=e.target,r=l(o);if(!r||e.defaultPrevented||s(w,"embed")||s(o,"embed")&&/\.pdf/i.test(o.src))return!0;var a=e.wheelDeltaX||0,i=e.wheelDeltaY||0;return a||i||(i=e.wheelDelta||0),!v.touchpadSupport&&f(i)?!0:(Math.abs(a)>1.2&&(a*=v.stepSize/120),Math.abs(i)>1.2&&(i*=v.stepSize/120),n(r,-a,-i),void e.preventDefault())}function r(e){var t=e.target,o=e.ctrlKey||e.altKey||e.metaKey||e.shiftKey&&e.keyCode!==H.spacebar;if(/input|textarea|select|embed/i.test(t.nodeName)||t.isContentEditable||e.defaultPrevented||o)return!0;if(s(t,"button")&&e.keyCode===H.spacebar)return!0;var r,a=0,i=0,u=l(w),c=u.clientHeight;switch(u==document.body&&(c=window.innerHeight),e.keyCode){case H.up:i=-v.arrowScroll;break;case H.down:i=v.arrowScroll;break;case H.spacebar:r=e.shiftKey?1:-1,i=-r*c*.9;break;case H.pageup:i=.9*-c;break;case H.pagedown:i=.9*c;break;case H.home:i=-u.scrollTop;break;case H.end:var d=u.scrollHeight-u.scrollTop-c;i=d>0?d+10:0;break;case H.left:a=-v.arrowScroll;break;case H.right:a=v.arrowScroll;break;default:return!0}n(u,a,i),e.preventDefault()}function a(e){w=e.target}function i(e,t){for(var n=e.length;n--;)E[A(e[n])]=t;return t}function l(e){var t=[],n=S.scrollHeight;do{var o=E[A(e)];if(o)return i(t,o);if(t.push(e),n===e.scrollHeight){if(!y||S.clientHeight+10<n)return i(t,document.body)}else if(e.clientHeight+10<e.scrollHeight&&(overflow=getComputedStyle(e,"").getPropertyValue("overflow-y"),"scroll"===overflow||"auto"===overflow))return i(t,e)}while(e=e.parentNode)}function u(e,t,n){window.addEventListener(e,t,n||!1)}function c(e,t,n){window.removeEventListener(e,t,n||!1)}function s(e,t){return(e.nodeName||"").toLowerCase()===t.toLowerCase()}function d(e,t){e=e>0?1:-1,t=t>0?1:-1,(k.x!==e||k.y!==t)&&(k.x=e,k.y=t,M=[],C=0)}function f(e){if(e){e=Math.abs(e),D.push(e),D.shift(),clearTimeout(z);var t=h(D[0],120)&&h(D[1],120)&&h(D[2],120);return!t}}function h(e,t){return Math.floor(e/t)==e/t}function m(e){var t,n,o;return e*=v.pulseScale,1>e?t=e-(1-Math.exp(-e)):(n=Math.exp(-1),e-=1,o=1-Math.exp(-e),t=n+o*(1-n)),t*v.pulseNormalize}function p(e){return e>=1?1:0>=e?0:(1==v.pulseNormalize&&(v.pulseNormalize/=m(1)),m(e))}var w,g={frameRate:150,animationTime:1e3,stepSize:100,pulseAlgorithm:!0,pulseScale:8,pulseNormalize:1,accelerationDelta:20,accelerationMax:1,keyboardSupport:!0,arrowScroll:50,touchpadSupport:!0,fixedBackground:!0,excluded:""},v=g,b=!1,y=!1,k={x:0,y:0},x=!1,S=document.documentElement,D=[120,120,120],H={left:37,up:38,right:39,down:40,spacebar:32,pageup:33,pagedown:34,end:35,home:36},v=g,M=[],T=!1,C=+new Date,E={};setInterval(function(){E={}},1e4);var z,A=function(){var e=0;return function(t){return t.uniqueID||(t.uniqueID=e++)}}(),N=function(){return window.requestAnimationFrame||window.webkitRequestAnimationFrame||function(e,t,n){window.setTimeout(e,n||1e3/60)}}(),K=/chrome/i.test(window.navigator.userAgent),L=null;"onwheel"in document.createElement("div")?L="wheel":"onmousewheel"in document.createElement("div")&&(L="mousewheel"),L&&K&&(u(L,o),u("mousedown",a),u("load",t))}();
попробуйте удалить и очистьте кеш на сайте.