.atoms-container-wrapper{background-color:#f0f4f8;padding:40px 20px;min-height:100vh;display:flex;justify-content:center;align-items:flex-start;background-image:url(/images/chemistry-background.png);background-size:cover;background-position:50%;background-repeat:no-repeat;box-sizing:border-box}.atoms-container{padding:0 20px 20px}.atoms-container,.atoms-container-2{width:100%;max-width:1500px;background-color:#fff;border-radius:12px;box-shadow:0 6px 18px rgba(0,0,0,.12);text-align:left;box-sizing:border-box}.atoms-container-2{margin:0 auto;padding:28px 32px 32px}.atoms-title{font-size:32px;display:flex;align-items:center;gap:15px;margin-bottom:10px;flex-wrap:wrap}.atoms-info-panel{margin:0 0 24px}.atoms-info-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.atoms-info-card{background:linear-gradient(180deg,#f8fcff,#eef6fb);border:1px solid #d8e6ef;border-radius:14px;padding:18px}.atoms-info-title{font-size:1rem;font-weight:700;margin:0 0 8px;color:#2c3e50}.atoms-info-card p{margin:0;color:#3a4757;line-height:1.6}.atoms-info-card a{color:#0f766e;font-weight:700;text-decoration:none}.atoms-info-card a:hover{text-decoration:underline}@media (max-width:768px){.atoms-title{flex-direction:column;align-items:flex-start;gap:8px}.atoms-info-grid{grid-template-columns:1fr}}.start-exercises-btn{font-size:.9rem;background:#0ea5e9;color:#fff;padding:6px 12px;border-radius:8px;text-decoration:none;transition:background .2s ease}.start-exercises-btn:hover{background:#0284c7}.atoms-category-wrapper{display:flex;flex-wrap:wrap;justify-content:center;gap:20px;padding:20px 0}.atoms-category-box{flex:1 1 calc(25% - 20px);max-width:300px;border:1px solid #e3edf3;border-radius:12px;background-color:#fff;box-shadow:0 5px 14px rgba(15,23,42,.08);overflow:hidden}.atoms-category-title{font-size:16px;font-weight:700;text-align:center;background:linear-gradient(180deg,#f8fcff,#eef6fb);color:#2c3e50;padding:12px 10px}.atoms-button,.test-basic-button{display:flex!important;justify-content:space-between;align-items:center;width:100%!important;padding:10px 14px;margin:8px auto;border-radius:8px;color:#fff;text-decoration:none;box-sizing:border-box;transition:background-color .2s ease,transform .2s ease}.atoms-button{background-color:#5d74b3!important}.atoms-button:hover{background-color:#005f99;color:#fff;transform:translateY(-1px)}.test-basic-button{background-color:#27ac6b!important}.test-basic-button:hover{background-color:#218838;color:#fff;transform:translateY(-1px)}.completion-star{width:20px;height:20px;margin-left:8px;flex-shrink:0}.atoms-heading-2{font-size:25px;font-weight:700;margin-bottom:15px;color:#0077b6}.atoms-subheading-2{font-size:21px;font-weight:600;margin:14px 0;color:#005f73}.atoms-text-2{font-size:18px;line-height:1.55;margin-bottom:18px;color:#333}.atoms-image-2{max-width:100%;height:auto;margin:14px 0}.atoms-list-2{font-size:18px;margin-left:22px;list-style-type:disc}.atoms-list-item-2{margin-bottom:12px}.atoms-list-item-2 strong{color:#007b83;margin-right:6px}.atom-model-container{max-width:1000px;margin:30px 0;padding:24px;background-color:#f0f0f0;border:2px solid #0077b6;border-radius:12px;text-align:left;box-shadow:0 6px 16px rgba(0,0,0,.15)}.test-text{margin-bottom:25px}.test-heading{font-size:32px;color:#0077b6;margin-bottom:18px}.test-paragraph{font-size:17px;line-height:1.55;margin-bottom:12px}.exercise-callout,.exercise-info-card{margin:28px 0;padding:24px;border-radius:14px}.exercise-info-card{background:linear-gradient(180deg,#f8fcff,#eef7fb);border:1px solid #d7e8f1}.exercise-callout{background:#f4fbf5;border:1px solid #d6eedc}.exercise-info-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:20px}.exercise-info-block{background-color:#fff;border-radius:12px;padding:18px 20px;border:1px solid #e3edf3}.exercise-info-title{font-size:19px;font-weight:600;color:#005f73;margin-bottom:12px}.exercise-sample-list{margin:0 0 18px 24px;padding:0}.exercise-sample-item{font-size:17px;line-height:1.6;color:#333;margin-bottom:12px}.test-navigation{display:flex;justify-content:center;margin-top:35px}.button-box,.button-box-inline{display:flex;gap:18px;align-items:center}.button-box a,.button-box-inline a{display:inline-flex;align-items:center;justify-content:center;white-space:nowrap;line-height:1.2;padding:12px 26px;border-radius:12px;font-size:1rem;text-decoration:none}.all-exercises-btn{background-color:#6c757d;color:#fff}.all-exercises-btn:hover{background-color:#5a6268}.go-to-next-topic-btn{background-color:#28a745;color:#fff}.go-to-next-topic-btn:hover{background-color:#218838}.button-box i,.button-box-inline i{margin-left:10px}@media (max-width:768px){.atoms-container-wrapper{padding:20px 12px;max-width:100vw;overflow-x:hidden}.atoms-container{max-width:100%;padding:24px 18px;border-radius:0}.atoms-container-2{width:100%;max-width:100%!important;padding:24px 18px;border-radius:0;box-sizing:border-box}.exercise-callout,.exercise-info-block,.exercise-info-card{padding:18px}.exercise-info-grid{grid-template-columns:1fr}.exercise-sample-list{margin-left:20px}.button-box,.button-box-inline{flex-direction:column;gap:12px}.atoms-category-box{flex:1 1 100%;max-width:100%}}