/* Modern responsive shell refinements */
:root{--app-red:#c62828;--app-radius:1.25rem;--app-shadow:0 18px 55px rgba(15,23,42,.10)}
.app-card,.modal-panel,.stat-tile{border-radius:var(--app-radius);box-shadow:var(--app-shadow)}
#mainApp{background:linear-gradient(180deg,#f8fafc 0%,#eef2f7 100%)}
#sidebar{backdrop-filter:saturate(1.2) blur(12px);border-right:1px solid rgba(148,163,184,.22)}
#sidebar nav button{transition:transform .16s ease,background-color .16s ease,color .16s ease}
#sidebar nav button:hover{transform:translateX(2px)}
#bottomNav{padding-bottom:env(safe-area-inset-bottom);box-shadow:0 -16px 40px rgba(15,23,42,.12)}
.nav-btn.active,.nav-btn[aria-current="page"]{color:var(--app-red);font-weight:800}
button,input,select,textarea{touch-action:manipulation}
.page-section{animation:maFade .18s ease-out}@keyframes maFade{from{opacity:0;transform:translateY(4px)}to{opacity:1;transform:none}}
@media(max-width:767px){header{position:sticky;top:0;z-index:35;background:rgba(255,255,255,.92);backdrop-filter:blur(16px)}main{padding-bottom:calc(88px + env(safe-area-inset-bottom))}.app-hero{border-radius:1.75rem}}