window.addEvent('domready', function() {  
    $('scroll_in').setStyle('width',$$('.scroll_item').length*150); 
});

var t;
function start_scroll_left(){
    t = window.setInterval('scroll_left()',5);
}
function start_scroll_right(){    
    t = window.setInterval('scroll_right()',5);
}
function scroll_left(){
    cur_x = parseInt($('scroll_in').getStyle('left')) ;
    if(cur_x < 0){
        $('scroll_in').setStyle('left', parseInt($('scroll_in').getStyle('left'))+1); 
    }                                                      
}
function scroll_right(){     
    max_x = 5-(($$('.scroll_item').length*150)-parseInt($('scroll_box').getStyle('width')));
    cur_x = parseInt($('scroll_in').getStyle('left')) ;
    if(cur_x > max_x){
        $('scroll_in').setStyle('left', parseInt($('scroll_in').getStyle('left'))-1); 
    }
}
function stop_scroll(){
    window.clearInterval(t);
}