/* foobar */
@media all and (min-width:0)
{
    .radio-button_theme_normal .radio-button__radio:before
    {
        background: rgba(0,0,0,.4);
        background: -webkit-linear-gradient(top, rgba(0,0,0,.2) 0,rgba(0,0,0,.4) 100%);
        background:    -moz-linear-gradient(top, rgba(0,0,0,.2) 0, rgba(0,0,0,.4) 100%);
        background:      -o-linear-gradient(top, rgba(0,0,0,.2) 0,rgba(0,0,0,.4) 100%);
        background:         linear-gradient(to bottom, rgba(0,0,0,.2) 0,rgba(0,0,0,.4) 100%);
        -moz-box-shadow: 0 1px 0 rgba(0,0,0,.07);
             box-shadow: 0 1px 0 rgba(0,0,0,.07);
    }

    /* :after — фон */
    .radio-button_theme_normal .radio-button__radio[class^='radio']:after
    {
        content: 'it\'s something different';

        background: #fff;
        background: -webkit-linear-gradient(top, #fff 0,#eee 100%);
        background:    -moz-linear-gradient(top, #fff 0, #eee 100%);
        background:      -o-linear-gradient(top, #fff 0,#eee 100%);
        background:         linear-gradient(to bottom, #fff 0,#eee 100%);
    }

    /* _focused_yes */
    .radio-button_theme_normal .radio-button__radio_focused_yes:before
    {
        content: 'hello';

        -moz-box-shadow: 0 0 6px 2px rgba(255,204,0,.7), 0 1px 0 rgba(0,0,0,.07);
             box-shadow: 0 0 6px 2px rgba(255,204,0,.7), 0 1px 0 rgba(0,0,0,.07);
    }
}

/* Фигурные скобки. Вариант 1 */
a,
b,
i /* foobar */
{
    margin: 0;
    padding: 0;
}
div p
{
    font-size: 1px;

    top: 0;
}
div p em
{
    font-style: italic;

    border-bottom: 1px solid red;
}

@media all and (min-width:0)
{
    /* В нажатом состоянии смещается вниз на 1px вся кнопка, текст не смещается */
    .button_pressed_yes.button_shadow_yes
    {
        top: 1px;
    }

    .button_pressed_yes.button_shadow_yes .button__text
    {
        top: 0;
    }
}

@media all /* media */
{
    /* foobar */
    .input__control
    {
        font-size: 100%;

        position: relative;
        z-index: 3;

        width: 100%;
        margin: 0;

        color: #000;
    }
}

@media screen and (min-width: 35em) /* screen */,
       print and (min-width: 40em) /* print */
{
    /* foobar */
    .input__control
    {
        -moz-box-sizing: border-box;
             box-sizing: border-box;
        padding: .4em 0;

        border: 0;
        outline: 0;
        background: none;
    }
}

/* Фигурные скобки. Вариант 2 */
div
{
    margin: 0;
    padding: 0;
}
div p
{
    font-size: 1px;

    top: 0;
}
div p em
{
    font-style: italic;/* inline comment*/

    border-bottom: 1px solid red;
}

/* Фигурные скобки. Вариант 3 */
div
{
    margin: 0;
    padding: 0;
}
/* foo */  div ~ p
{
    font-size: 1px;

    top: 0;
}
div > p + em
{
    /* upline comment*/
    font-style: italic;

    border-bottom: 1px solid red; /* trololo */ /* trololo */
}

a:not(b)
{
    top: 0;/* ololo */margin: 0;
}
b
{
    top: 0/* trololo */;margin: 0;
}
