function zasifrovatHesloPrihlaseni() {
  document.prihlaseni.heslo.value = SHA1(document.prihlaseni.sul.value + SHA1(document.prihlaseni.heslo.value));
  document.prihlaseni.sul.value = "";  
}

function zobrazit() {
  document.getElementById("prihlaseni").style.visibility = 'visible';
}
  
function skryt() {
  document.getElementById("prihlaseni").style.visibility = 'hidden';
}
  
function zobrazitref() {
  document.getElementById("reference").style.visibility = 'visible';
}
  
function skrytref() {
  document.getElementById("reference").style.visibility = 'hidden';
}

$(document).ready(function () {
    var currentPosition = 0;
    var slideWidth = 850;
    var slides = $('.slide');
    var numberOfSlides = slides.length;

    // Remove scrollbar in JS
    $('#slidesContainer').css('overflow', 'hidden');

    // Wrap all .slides with #slideInner div
    slides
    .wrapAll('<div id="slideInner"></div>')
    // Float left to display horizontally, readjust .slides width
       .css({
   'float': 'left',
   'width': slideWidth
       });

    // Set #slideInner width equal to total width of all slides
    $('#slideInner').css('width', slideWidth * numberOfSlides);

    // Insert controls in the DOM
    $('#slideshow')
    .prepend('<span class="control" id="leftControl">Předchozí slide</span>')
    .append('<span class="control" id="rightControl">Další slide</span>');

    // Hide left arrow control on first load
    manageControls(currentPosition);

    // Create event listeners for .controls clicks
    $('.control')
    .bind('click', function () {
        // Determine new position
        currentPosition = ($(this).attr('id') == 'rightControl') ? currentPosition + 1 : currentPosition - 1;

        // Hide / show controls
        manageControls(currentPosition);
        // Move slideInner using margin-left
        $('#slideInner').animate({
            'marginLeft': slideWidth * (-currentPosition)
        });
    });

    // manageControls: Hides and Shows controls depending on currentPosition
    function manageControls(position) {
        // Hide left arrow if position is first slide
        if (position == 0) { $('#leftControl').hide() } else { $('#leftControl').show() }
        // Hide right arrow if position is last slide
        if (position == numberOfSlides - 1) { $('#rightControl').hide() } else { $('#rightControl').show() }
    }
});