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0 .5rem}.explore-card-description{font-size:.9rem;line-height:1.6;color:var(--secondary-text-color);margin:0}.explore-card-button{display:flex;align-items:center;justify-content:space-between;width:100%;padding:1rem 1.5rem;background-color:#fafafa;border:none;border-top:1px solid var(--border-color);border-bottom-left-radius:16px;border-bottom-right-radius:16px;font-size:.9rem;font-weight:600;color:var(--primary-text-color);cursor:pointer;transition:background-color .2s,color .2s}.explore-card-button:hover{background-color:var(--accent-color);color:var(--surface-color)}.skeleton-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:1.5rem;padding:1rem}.skeleton-card{background:#fff;border-radius:12px;padding:1.5rem;box-shadow:0 3px 8px #00000014;display:flex;flex-direction:column;gap:1rem;overflow:hidden;position:relative}.skeleton-shimmer{position:relative;overflow:hidden;background:linear-gradient(90deg,#ececec 25%,#f6f6f6 37%,#ececec 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li{margin-left:1.5rem;list-style:disc;color:#444}.ask-ai-fab{position:fixed;bottom:20px;right:20px;background-color:var(--accent-color);color:var(--surface-color);border:none;border-radius:30px;padding:.8rem 1.5rem;display:flex;align-items:center;gap:.5rem;font-size:1rem;font-weight:600;cursor:pointer;box-shadow:0 8px 16px #0003;transition:background-color .2s ease,transform .2s ease,box-shadow .2s ease;z-index:999}.ask-ai-fab:hover{background-color:#333;transform:translateY(-3px);box-shadow:0 12px 20px #00000040}.ask-ai-fab svg{font-size:1.2rem}.mcq-page{font-family:Inter,sans-serif;background-color:var(--bg-color);min-height:calc(100vh - 130px);display:flex;align-items:center;justify-content:center;padding:1.5rem}.mcq-card{background-color:var(--surface-color);border:1px solid var(--border-color);border-radius:16px;padding:2.5rem;box-shadow:0 8px 32px 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ease}.mcq-option-button:hover{border-color:var(--accent-color);background-color:#fafafa}.mcq-option-button.selected{background-color:var(--accent-color);color:var(--surface-color);border-color:var(--accent-color)}.mcq-footer{margin-top:2.5rem;text-align:right}.mcq-nav-button{padding:.8rem 2rem;font-size:1rem;font-weight:600;background-color:var(--accent-color);color:var(--surface-color);border:none;border-radius:8px;cursor:pointer;transition:background-color .2s}.mcq-nav-button:disabled{background-color:#ccc;cursor:not-allowed}.results-page{text-align:center}.results-title{font-size:2rem;color:var(--primary-text-color);margin-bottom:.5rem}.results-score{font-size:1.2rem;color:var(--secondary-text-color);margin-bottom:2.5rem}.results-summary{text-align:left;margin-bottom:2.5rem}.summary-item{display:flex;align-items:center;gap:1rem;padding:.75rem 0;border-bottom:1px solid var(--border-color)}.summary-item:last-child{border-bottom:none}.summary-icon{font-size:1.5rem}.summary-icon.correct{color:#28a745}.summary-icon.incorrect{color:#dc3545}.manage-class-page{font-family:Inter,sans-serif;background-color:var(--bg-color);min-height:100vh;padding:1.5rem}.page-header{display:flex;justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto 1.5rem}.back-button,.add-student-button{display:inline-flex;align-items:center;gap:.5rem;background:none;border:1px solid var(--border-color);padding:.6rem 1.2rem;border-radius:8px;font-size:.9rem;font-weight:500;cursor:pointer;transition:all .2s ease}.add-student-button{background-color:var(--accent-color);color:var(--surface-color);border-color:var(--accent-color)}.back-button:hover{background-color:var(--surface-color)}.add-student-button:hover{background-color:#333}.class-title-header{text-align:center;max-width:800px;margin:2rem auto}.class-title-header h1{font-size:2.5rem;margin:0 0 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label{font-size:.8rem;font-weight:600;color:var(--secondary-text-color);text-transform:uppercase;margin-bottom:.5rem}.input-wrapper{position:relative}.input-icon{position:absolute;left:1rem;top:50%;transform:translateY(-50%);color:var(--secondary-text-color)}.input-wrapper input{width:100%;padding:.9rem 1rem .9rem 3rem;border:1px solid var(--border-color);border-radius:8px;font-size:1rem;font-family:Inter,sans-serif;background-color:#fcfcfc;color:var(--primary-text-color);transition:all .2s ease-in-out;box-sizing:border-box}.input-wrapper input:focus{outline:none;border-color:var(--primary-text-color);box-shadow:0 0 0 4px #0000000d}.error-message{color:#ef4444;font-size:.9rem;font-weight:500;text-align:center;margin:-.5rem 0 .5rem}.save-button{display:flex;align-items:center;justify-content:center;gap:.75rem;width:100%;padding:1rem;font-size:1rem;font-weight:600;border-radius:8px;cursor:pointer;background-color:var(--accent-color);color:var(--surface-color);border:none;transition:background-color .2s ease;margin-top:1rem}.save-button:disabled{background-color:#ccc;cursor:not-allowed}.loading-spinner{animation:spin 1.5s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}