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cubic-bezier(.22,1,.36,1);display:flex;position:relative}.mb-nav-item:active{opacity:.75;transform:scale(.94)}.mb-nav-item.active{color:var(--text-primary)}.mb-nav-item.active:after{content:"";background:var(--accent);border-radius:1px;width:24px;height:2px;position:absolute;top:0;left:50%;transform:translate(-50%)}.mb-nav-label{letter-spacing:-.01em;font-size:10px;font-weight:500}.mb-nav-item.active .mb-nav-label{color:var(--text-primary);font-weight:600}.mb-nav-subject-wrapper{flex-direction:column;flex:1;justify-content:center;align-items:center;gap:2px;display:flex}.mb-nav-subject-toggle{cursor:pointer;background:0 0;border:none;margin-top:-2px;padding:0}.mb-subject-overlay{z-index:150;background:#0006;animation:.2s fade-in;position:fixed;inset:0}@keyframes fade-in{0%{opacity:0}to{opacity:1}}.mb-subject-menu{background:var(--bg-surface);border-radius:var(--radius-xl) var(--radius-xl) 0 0;box-shadow:var(--shadow-xl);z-index:200;max-height:70vh;animation:.25s 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