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var(--border);box-shadow:var(--shadow-sm)}.lesson-select{padding:.625rem 1rem;font-size:.9rem;border:2px solid var(--border);border-radius:var(--radius-md);background:var(--bg-card);min-width:300px;font-weight:500;transition:all var(--transition-fast)}.lesson-select:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #3b82f61a}.lesson-editor-actions{display:flex;gap:.5rem}.lesson-editor-container{height:500px;border-radius:var(--radius-lg);overflow:hidden;border:1px solid var(--border);box-shadow:var(--shadow-sm)}.editor-error{padding:.875rem 1rem;background:linear-gradient(135deg,#fef2f2,#fee2e2);border:1px solid #fecaca;border-radius:var(--radius-md);color:var(--error);margin-bottom:1rem;font-weight:500}.editor-success{padding:.875rem 1rem;background:linear-gradient(135deg,#f0fdf4,#dcfce7);border:1px solid #bbf7d0;border-radius:var(--radius-md);color:var(--success);margin-bottom:1rem;font-weight:500}.editor-json-error{padding:.875rem 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