.child-navigation{position:sticky;top:0;z-index:20;display:flex;gap:12px;align-items:stretch;padding:10px 0;background:var(--cream,#f8f7ed);border-bottom:1px solid var(--line);box-shadow:0 5px 9px -9px #174d4666}
.child-navigation[hidden]{display:none}
.child-navigation button{min-height:64px;border-radius:16px;display:flex;align-items:center;justify-content:center;gap:12px;padding:10px 18px;font-weight:700}
.nav-back{flex:1;min-width:0;background:var(--green);color:white;border:2px solid var(--green);text-align:left}
.nav-back>span:last-child{min-width:0}
.nav-arrow{font-size:32px;line-height:1;flex:none}
.nav-back small,.nav-back strong{display:block}
.nav-back small{font-size:11px;font-weight:500;opacity:.85;margin-bottom:3px}
.nav-back strong{font-size:19px;line-height:1.4;overflow-wrap:anywhere}
.nav-home{flex:none;background:#fff9e6;color:var(--green);border:2px solid #dbc88c;font-size:17px}
.nav-home svg{width:23px;height:23px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.child-navigation button:active{transform:translateY(1px)}
.child-navigation button:disabled{cursor:wait;opacity:.7}
#screen:focus{outline:none}
.vocabulary-heading,.tab-list,[data-action="next"]{scroll-margin-top:100px}
@supports(padding:env(safe-area-inset-top)){.child-navigation{padding-top:calc(10px + env(safe-area-inset-top))}.vocabulary-heading,.tab-list,[data-action="next"]{scroll-margin-top:calc(100px + env(safe-area-inset-top))}}
@media(max-width:480px){.child-navigation{gap:9px}.child-navigation button{min-height:60px;padding:9px 12px;gap:9px;border-radius:14px}.nav-back strong{font-size:16px}.nav-arrow{font-size:28px}.nav-home{font-size:15px}.nav-home svg{width:21px;height:21px}}