.bottom-nav{position:fixed;bottom:0;left:0;right:0;background-color:#e5e5e5;border-radius:8px 8px 0 0;z-index:100;padding:10px 0}@media (prefers-color-scheme:dark){.bottom-nav{background-color:#2a2a2a;border-top-color:rgba(255,255,255,.1)}}.bottom-nav__container{max-width:1280px;margin:0 auto;padding:0 10px;display:flex;align-items:center;justify-content:space-around;gap:10px}.bottom-nav__button{background:none;border:none;padding:5px;cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--foreground);transition:opacity .2s ease-in-out;flex:1 1;max-width:60px}.bottom-nav__button:hover{opacity:.7}.bottom-nav__button:active{opacity:.5}.bottom-nav__button svg{width:24px;height:24px;stroke:currentColor;fill:none}.navigation-menu-overlay{position:fixed;top:0;left:0;right:0;bottom:0;background-color:rgba(0,0,0,.7);z-index:9999;display:flex;align-items:center;justify-content:center;animation:fadeIn .2s ease-in-out}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.navigation-menu{background-color:#e5e5e5;width:100%;max-width:600px;max-height:100vh;box-shadow:0 10px 40px rgba(0,0,0,.2);display:flex;flex-direction:column;overflow:hidden;animation:slideUp .3s ease-out}@keyframes slideUp{0%{transform:translateY(20px);opacity:0}to{transform:translateY(0);opacity:1}}.navigation-menu__header{display:flex;align-items:center;justify-content:space-between;padding:1.5rem;border-bottom:1px solid #e5e7eb}.navigation-menu__title{font-size:1.5rem;font-weight:600;margin:0;font-family:var(--font-lexend)}.navigation-menu__close{background:none;border:none;cursor:pointer;padding:.5rem;display:flex;align-items:center;justify-content:center;color:#6b7280;transition:color .2s}.navigation-menu__close:hover{color:#111827}.navigation-menu__content{overflow-y:auto;padding:1rem;flex:1 1}.navigation-menu__topic-group{margin-bottom:.5rem}.navigation-menu__topic-header{display:flex;align-items:center;gap:.5rem;background-color:#eee;border-radius:8px;border:1px solid #bbb}.navigation-menu__topic-toggle{background:none;border:none;cursor:pointer;padding:.5rem;display:flex;align-items:center;justify-content:center;color:#6b7280;transition:transform .2s,color .2s;flex-shrink:0}.navigation-menu__topic-toggle:hover{color:#111827}.navigation-menu__chevron{transition:transform .2s;transform:rotate(0deg)}.navigation-menu__chevron--expanded{transform:rotate(90deg)}.navigation-menu__topic-content{max-height:0;overflow:hidden;transition:max-height .3s ease-out;margin-left:2rem}.navigation-menu__topic-content--expanded{max-height:5000px;transition:max-height .3s ease-in}.navigation-menu__section-group{margin-top:.25rem}.navigation-menu__section-header{display:flex;align-items:center;gap:.5rem;background-color:#ddd;border-radius:8px;border:1px solid #bbb}.navigation-menu__section-toggle{background:none;border:none;cursor:pointer;padding:.25rem;display:flex;align-items:center;justify-content:center;color:#6b7280;transition:transform .2s,color .2s;flex-shrink:0}.navigation-menu__section-toggle:hover{color:#111827}.navigation-menu__section-content{max-height:0;overflow:hidden;transition:max-height .3s ease-out;margin-left:1.5rem}.navigation-menu__section-content--expanded{max-height:2000px;transition:max-height .3s ease-in}.navigation-menu__item{display:flex;align-items:center;padding:.75rem 1rem;text-decoration:none;color:#374151;border-radius:8px;transition:background-color .2s,color .2s;margin-bottom:.25rem}.navigation-menu__item:hover{background-color:#f3f4f6;color:#111827}.navigation-menu__item--active{background-color:skyblue;color:white;font-weight:500}.navigation-menu__item--active:hover{background-color:#2563eb;color:white}.navigation-menu__item--home{font-weight:600;margin-bottom:1rem;border-bottom:1px solid #e5e7eb;padding-bottom:1rem}.navigation-menu__item--topic{font-weight:600;font-size:1.1rem;color:#111827}.navigation-menu__item--section{font-weight:500;color:#4b5563}.navigation-menu__item--activity{font-weight:400;color:#6b7280;font-size:.95rem}.navigation-menu__item-icon{margin-right:.75rem;font-size:1.25rem}.navigation-menu__item-title{flex:1 1}.navigation-menu__content::-webkit-scrollbar{width:8px}.navigation-menu__content::-webkit-scrollbar-track{background:#f1f1f1;border-radius:4px}.navigation-menu__content::-webkit-scrollbar-thumb{background:#cbd5e1;border-radius:4px}.navigation-menu__content::-webkit-scrollbar-thumb:hover{background:#94a3b8}