@mixin extjs-form-fieldset {
    .#{$prefix}fieldset {
        border: $fieldset-border;
        
        padding: $fieldset-padding;
        margin-bottom: $fieldset-padding;
        
        display: block; /* preserve margins in IE */
        position: relative;
    }

    // Insane IE bug: Fieldset padding-top is rendered *outside* the border!
    // So we transfer the padding-top to the body element.
    .#{$prefix}ie .#{$prefix}fieldset {
        padding-top: 0;
        .#{$prefix}fieldset-body {
            padding-top: $fieldset-padding;
        }
    }

    .#{$prefix}fieldset-header-checkbox {
        line-height: $fieldset-header-line-height;
    }

    .#{$prefix}fieldset-header {
        font: $fieldset-header-font;
        color: $fieldset-header-color;
        padding: $fieldset-header-padding;
        overflow: hidden; // fixes a webkit bug where legend elements that have floated children are not displayed

        .#{$prefix}fieldset-header-text {
            float: left;
            padding: 1px 0;
        }
        .#{$prefix}fieldset-header-text-collapsible {
            cursor: pointer;
        }
        
        .#{$prefix}form-item,
        .#{$prefix}tool {
            float: left;
            margin: 1px 0 0 0;
        }

        .#{$prefix}form-cb-wrap {
            padding: 1px 0;
            font-size: 0;
            line-height: 0;
        }
    }

    .#{$prefix}fieldset-with-title {
        .#{$prefix}form-item,
        .#{$prefix}tool {
            margin-right: 3px;
        }
    }

    // Use Webkit's built-in fieldset legend padding which takes precedence over padding-left/right
    .#{$prefix}webkit {
        .#{$prefix}fieldset-header {
            -webkit-padding-start: #{left($fieldset-header-padding)};
            -webkit-padding-end: #{right($fieldset-header-padding)};
        }
    }

    // opera renders an invisible border above the fieldset in addition to the normal border when the fieldset has a legend.
    // To compensate for this, give the fieldset a negative top margin equal to the top border width.
    @if $include-opera {
        .#{$prefix}opera {
            .#{$prefix}fieldset-with-legend {
                margin-top: -#{top($fieldset-border-width)};
            }
            &.#{$prefix}mac .#{$prefix}fieldset-header-text {
                padding: 2px 0 0;
            }
        }
    }
    // IE8 strict has a problem similar to opera's, except the invisible top border only changes the position of
    // the legend element, so we have to adjust the position of the legend using a negative top margin.
    @if $include-ie {
        .#{$prefix}strict .#{$prefix}ie8 .#{$prefix}fieldset-header {
            margin-bottom: -#{top($fieldset-border-width)};
            .#{$prefix}tool,
            .#{$prefix}fieldset-header-text,
            .#{$prefix}fieldset-header-checkbox {
                position: relative;
                top: -#{top($fieldset-border-width)};
            }
        }
    }

    @if $include-ie {
        .#{$prefix}quirks .#{$prefix}ie,
        .#{$prefix}ie8m {
            .#{$prefix}fieldset-header {
                padding-left: #{left($fieldset-header-padding) - 2};
                padding-right: #{right($fieldset-header-padding) - 2};
            }
        }
    }

    .#{$prefix}fieldset-collapsed {
        .#{$prefix}fieldset-body {
            display: none;
        }
    }

    .#{$prefix}fieldset-collapsed {
        padding-bottom: 0 !important;
        
        border-width: 1px 1px 0 1px !important;
        border-left-color: transparent !important;
        border-right-color: transparent !important;
    }

    @if $include-ie {
        .#{$prefix}ie6 .#{$prefix}fieldset-collapsed {
            border-width: 1px 0 0 0 !important;

            padding-bottom: 0 !important;
            margin-left: 1px;
            margin-right: 1px;
        }

        .#{$prefix}ie .#{$prefix}fieldset-bwrap {
            zoom: 1;
        }
    }

    @if $include-ie {
        /* IE legend positioning bug */
        .#{$prefix}ie .#{$prefix}fieldset-noborder legend {
            position: relative;

            margin-bottom: 23px;
        }

        .#{$prefix}ie .#{$prefix}fieldset-noborder legend span {
            position: absolute;
            left: 16px;
        }
    }
    
    .#{$prefix}fieldset {
        overflow: hidden;
    }

    .#{$prefix}fieldset-bwrap {
        overflow: hidden;
        
        zoom: 1;
    }

    .#{$prefix}fieldset-body {
        overflow: hidden;
    }
}