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a:hover{background:#5a6fd6;transform:translateY(-1px)}@media(max-width:600px){.app-container{padding:24px 14px 40px}.app-container h1{font-size:1.8rem;margin-bottom:14px}.nav-bar a{padding:8px 12px;font-size:.85rem}.study-card-container{padding:20px}.card-flip-front p,.card-flip-back p{font-size:1.8rem}.card-flip-front,.card-flip-back{padding:30px 20px}.quality-buttons{flex-wrap:wrap}.quality-buttons button{flex:1 1 40%}.study-nav-buttons{flex-wrap:wrap}.study-nav-buttons button{flex:1}.card-list-container li{flex-direction:column;align-items:flex-start;gap:10px}.card-actions{margin-left:0;width:100%}.card-actions button{flex:1}.card-edit-inputs{flex-direction:column}.stats-grid{grid-template-columns:1fr 1fr}}