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Contact Customer Service | The National Academies Press

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Note: hidden by default */ #mobile-menu .panel { padding: 0 0; background-color: transparent; max-height: 0; box-shadow: 0 !important; overflow: hidden; transition: max-height 0.2s ease-out; margin: 0px !important; border: 0 !important; } #mobile-menu .panel ul li { margin: 0px 0px; padding-left: 0px; } #mobile-menu .panel ul { margin-top: 10px; margin-bottom: 10px; padding-left: 0px; } #mobile-menu .panel ul li { line-height: 2; } #mobile-menu .panel ul li a { color: #000; text-decoration: underline; cursor: pointer; } .controls__menu-mobile { text-transform: uppercase; } .controls__menu-mobile svg { fill: #222; fill: var(--color-neutral--charcoal); width: 1.75rem; height: 1.75rem; } .cart-badge { display: inline-block; text-align: center; line-height: 1; background: #7899F2; color: white; font-weight: bold; border-radius: 20px; padding: 3px 6px; margin-left: 3px; } @media screen and (min-width: 65em) { #mobile-menu .controls__menu { display: inline; } } @media screen and (max-width: 65em) { #mobile-menu .controls__menu svg { display: inline; } } /*NAP mega menu dropdown*/ li.nap-mega-menu.mega-dropdown { position: static !important; width:100% !important; } .nap-mega-menu .mega-dropdown-menu { padding: 20px 0px; box-shadow: none; -webkit-box-shadow: none; margin-top: 10px !important; box-shadow: 0 5px 15px var(--box-shadow--charcoal); transform: none !important; top: 100% !important; } .nap-mega-menu .mega-dropdown-menu > li > ul.browse-col { padding: 0; margin: 0; width: 100%; } .nap-mega-menu .mega-dropdown-menu > li > ul > li { list-style: none; } .nap-mega-menu .mega-dropdown-menu > li > ul > li > a { display: block; padding: 3px 20px; clear: both; font-weight: normal; line-height: 1.428571429; color: #4148C2; white-space: normal; font-size: 14px; text-transform: none; } .nap-mega-menu .mega-dropdown-menu > li ul > li > a:hover, .nap-mega-menu .mega-dropdown-menu > li ul > li > a:focus { text-decoration: none; color: #444; background-color: #f5f5f5; } .nap-mega-menu .mega-dropdown-menu .dropdown-header a { color: #4148C2; font-size: 14px; font-weight: 900 !important; text-align: left; text-transform: uppercase !important; padding: 0px; margin-bottom: 7px; } .nap-mega-menu .mega-dropdown-menu form { margin:3px 20px; } .nap-mega-menu .mega-dropdown-menu .form-group { margin-bottom: 3px; } .nap-mega-menu .vertical-divider { border-left: 1px solid #ccc; } .nap-mega-menu .mega-dropdown-menu > li.d-flex { display: inline-flex !important; margin-right: 0 !important; justify-content: space-between; flex-wrap: nowrap !important; flex-direction: row !important; } #nap-mega-menu-inner { justify-content: space-between; align-content:start; } #nap-mega-menu-inner li.browse-col { width: 22%; } </style> <header class="global-nav global-nav--local menu-is-hidden search-is-hidden" id="lowerMenu"> <div class="container flex justify-between"> <!--Mega menu start --> <div aria-hidden="true" class="mega-menu" id="search"> <div data-lock=""> <div 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