/* SOLO canal público de VIDEO, activado por JS. Header original intacto al abrir. */
body.mtv-video-header-auto .site-header {
    box-sizing:border-box;
    overflow:hidden;
    max-height:var(--mtv-video-header-original,88px);
    min-height:0;
    transition:max-height .32s ease, height .32s ease, opacity .28s ease, transform .32s ease, padding .32s ease, border-width .32s ease;
}
body.mtv-video-header-auto.mtv-video-header-hidden .site-header {
    height:0!important;
    max-height:0!important;
    min-height:0!important;
    margin-block:0!important;
    padding-top:0!important;
    padding-bottom:0!important;
    border-bottom-width:0!important;
    overflow:hidden!important;
    opacity:0;
    transform:translateY(-12px);
    pointer-events:none;
    visibility:hidden;
}
/* Pestaña visible incluso cuando el header está cerrado; no ocupa espacio de documento. */
body.mtv-video-header-auto #mtv-video-menu-tab {
    position:fixed;top:0;left:50%;transform:translateX(-50%);
    z-index:10001;min-width:115px;min-height:30px;
    padding:5px 17px 7px;
    background:#16345a;color:#fff;border:1px solid #4884c3;border-top:0;
    border-radius:0 0 13px 13px;box-shadow:0 5px 16px rgba(0,0,0,.23);
    font:700 12px/1.2 system-ui,Arial,sans-serif;text-align:center;
    cursor:pointer;touch-action:manipulation;
}
body.mtv-video-header-auto #mtv-video-menu-tab:focus-visible {outline:3px solid #ffe08c;outline-offset:2px;}
body.mtv-video-header-auto:not(.mtv-video-header-hidden) #mtv-video-menu-tab {
    top:var(--mtv-video-header-original,88px);
}
body.mtv-video-header-auto #mtv-video-menu-tab {transition:top .32s ease;}
/* No cambia dimensiones, fuentes ni nodos DOM del reproductor. */
@media(prefers-reduced-motion:reduce){
  body.mtv-video-header-auto .site-header,
  body.mtv-video-header-auto #mtv-video-menu-tab {transition:none!important;}
}