.nav-btn { align-items: center; background: var(--surface-alt); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--tub-shadow); color: var(--text-muted); cursor: pointer; display: flex; font-size: var(--text-sm); font-weight: var(--font-medium); gap: var(--space-3); min-height: var(--size-btn-lg); padding: var(--space-3) var(--space-4); text-decoration: none; transition: background-color 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease, color 0.15s ease, transform 0.15s ease; width: 100%; }
.nav-btn:active { transform: translateY(0); }
.nav-btn:hover { background: var(--surface-hover); color: var(--text); }
.nav-btn.active { background: rgba(var(--accent-rgb), 0.08); border-color: var(--accent); color: var(--text); }
.nav-btn__label { flex: 1; }
.nav-btn--admin:hover { border-color: var(--warning); }
.nav-btn--admin.active { background: rgba(var(--warning-rgb), 0.08); border-color: var(--warning); }
.nav-tub { background: var(--surface); border-right: 1px solid var(--border); display: flex; flex-direction: column; height: 100vh; left: 0; overflow-y: auto; position: fixed; top: 0; transform: translate3d(-100%, 0, 0); transition: transform 0.3s cubic-bezier(0.2, 0.8, 0.2, 1); width: var(--nav-width); will-change: transform; z-index: 110; }
.nav-tub.is-open { box-shadow: 0 0 60px rgba(0, 0, 0, 0.3); transform: translate3d(0, 0, 0); }
.nav-tub__brand { align-items: center; color: var(--accent); display: flex; filter: drop-shadow(0 2px 8px rgba(var(--accent-rgb), 0.3)); font-size: var(--text-lg); font-weight: var(--font-bold); gap: var(--space-3); letter-spacing: var(--letter-spacing-tight); text-decoration: none; text-transform: uppercase; }
.nav-tub__close { align-items: center; background: var(--surface-alt); border: none; border-radius: var(--radius); color: var(--text-muted); cursor: pointer; display: flex; height: var(--size-btn-lg); justify-content: center; transition: background-color 0.15s ease, color 0.15s ease, transform 0.15s ease; width: var(--size-btn-lg); }
.nav-tub__close:hover { background: var(--surface); color: var(--text); }
.nav-tub__content { display: flex; flex-direction: column; gap: var(--space-4); overflow-y: auto; padding: var(--space-4); padding-bottom: calc(var(--space-4) + env(safe-area-inset-bottom, 0px)); }
.nav-tub__group { display: flex; flex-direction: column; gap: var(--space-2); }
.nav-tub__group--admin .nav-tub__group-title { color: var(--warning); }
.nav-tub__group-title { color: var(--text-muted); font-size: var(--font-size-micro); font-weight: var(--font-semibold); letter-spacing: var(--letter-spacing-wide); padding: var(--space-2) var(--space-3); text-transform: uppercase; }
.nav-tub__header { align-items: center; border-bottom: 1px solid var(--border); display: flex; flex-shrink: 0; height: var(--header-height); justify-content: space-between; padding: 0 var(--space-4); }
.nav-tub__logo { flex-shrink: 0; height: var(--size-lg); width: var(--size-lg); }
.nav-tub__overlay { background: rgba(0, 0, 0, 0.6); backdrop-filter: blur(4px); cursor: pointer; height: 100vh; left: 0; opacity: 0; position: fixed; top: 0; transition: opacity 0.3s ease; visibility: hidden; width: 100vw; z-index: 100; }
.nav-tub__overlay.is-visible { opacity: 1; visibility: visible; }
@media (min-width: 1024px) {
.nav-tub { box-shadow: none; transform: none; }
.nav-tub__close { display: none; }
.nav-tub__overlay { display: none; }
}