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var(--border);border-radius:var(--radius-md);color:var(--text-primary);font-family:var(--font-body);font-size:var(--text-sm);transition:all var(--transition-base);outline:none}.input:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-glow);background:var(--bg-glass)}.input::placeholder{color:var(--text-tertiary)}.textarea{resize:vertical;min-height:100px;line-height:1.6}.select{-webkit-appearance:none;-moz-appearance:none;appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center;padding-right:36px}.label{display:block;font-size:var(--text-sm);font-weight:500;color:var(--text-secondary);margin-bottom:var(--space-2)}.badge{display:inline-flex;align-items:center;gap:var(--space-1);padding:var(--space-1) var(--space-3);font-size:var(--text-xs);font-weight:600;border-radius:var(--radius-full);background:var(--bg-glass);color:var(--text-secondary);border:1px solid var(--border)}.badge-primary{background:#7c3aed26;color:var(--primary-light);border-color:#7c3aed4d}.badge-secondary{background:#06b6d426;color:var(--secondary-light);border-color:#06b6d44d}.badge-accent{background:#10b98126;color:var(--accent-light);border-color:#10b9814d}.badge-warning{background:#f59e0b26;color:var(--warning-light);border-color:#f59e0b4d}.badge-danger{background:#ef444426;color:var(--danger-light);border-color:#ef44444d}.stat-card{background:var(--bg-card);-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border:1px solid var(--border);border-radius:var(--radius-xl);padding:var(--space-6);position:relative;overflow:hidden;transition:all var(--transition-base)}.stat-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:var(--border-light)}.stat-card .stat-icon{width:48px;height:48px;border-radius:var(--radius-lg);display:flex;align-items:center;justify-content:center;margin-bottom:var(--space-4);font-size:1.5rem}.stat-card .stat-value{font-family:var(--font-heading);font-size:var(--text-3xl);font-weight:700;color:var(--text-primary);line-height:1;margin-bottom:var(--space-1)}.stat-card .stat-label{font-size:var(--text-sm);color:var(--text-secondary)}.stat-card .stat-change{font-size:var(--text-xs);font-weight:600;display:flex;align-items:center;gap:var(--space-1);margin-top:var(--space-2)}.stat-change.positive{color:var(--accent)}.stat-change.negative{color:var(--danger)}.sidebar{position:fixed;top:0;left:0;width:var(--sidebar-width);height:100vh;background:var(--gradient-sidebar);border-right:1px solid var(--border);-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);z-index:var(--z-sidebar);display:flex;flex-direction:column;transition:width var(--transition-base);overflow-y:auto;overflow-x:hidden}.sidebar-logo{padding:var(--space-6);display:flex;align-items:center;gap:var(--space-3);border-bottom:1px solid var(--border)}.sidebar-logo .logo-icon{width:40px;height:40px;border-radius:var(--radius-lg);background:var(--gradient-primary);display:flex;align-items:center;justify-content:center;color:#fff;font-size:1.25rem;flex-shrink:0;box-shadow:var(--shadow-glow-primary)}.sidebar-logo 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.header{background:#f8fafccc}.header-search{flex:1;max-width:400px;position:relative}.header-search .search-icon{position:absolute;left:var(--space-3);top:50%;transform:translateY(-50%);color:var(--text-tertiary);width:16px;height:16px}.header-search input{width:100%;padding:var(--space-2) var(--space-4) var(--space-2) 36px;background:var(--bg-input);border:1px solid var(--border);border-radius:var(--radius-full);color:var(--text-primary);font-size:var(--text-sm);outline:none;transition:all var(--transition-base)}.header-search input:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-glow)}.header-search .search-shortcut{position:absolute;right:var(--space-3);top:50%;transform:translateY(-50%);font-size:var(--text-xs);color:var(--text-tertiary);background:var(--bg-glass);padding:2px 6px;border-radius:var(--radius-sm);border:1px solid 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h3{font-size:var(--text-xl)}.modal-body{padding:var(--space-6)}.modal-footer{display:flex;justify-content:flex-end;gap:var(--space-3);padding:var(--space-4) var(--space-6);border-top:1px solid var(--border)}.toast-container{position:fixed;bottom:var(--space-6);right:var(--space-6);z-index:var(--z-toast);display:flex;flex-direction:column;gap:var(--space-3)}.toast{display:flex;align-items:center;gap:var(--space-3);padding:var(--space-4) var(--space-5);background:var(--bg-secondary);border:1px solid var(--border);border-radius:var(--radius-lg);box-shadow:var(--shadow-xl);min-width:300px;animation:slideInRight .4s var(--transition-spring)}.toast.toast-success{border-left:3px solid var(--accent)}.toast.toast-error{border-left:3px solid var(--danger)}.toast.toast-warning{border-left:3px solid var(--warning)}.toast.toast-info{border-left:3px solid var(--secondary)}.tabs{display:flex;gap:var(--space-1);padding:var(--space-1);background:var(--bg-glass);border-radius:var(--radius-lg);border:1px solid var(--border);width:fit-content}.tab{padding:var(--space-2) var(--space-5);font-size:var(--text-sm);font-weight:500;color:var(--text-secondary);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);border:none;background:none;font-family:var(--font-body)}.tab:hover{color:var(--text-primary)}.tab.active{background:var(--primary);color:#fff;box-shadow:var(--shadow-sm)}.flashcard-container{perspective:1000px;width:100%;max-width:500px;height:320px;margin:0 auto}.flashcard{width:100%;height:100%;position:relative;transform-style:preserve-3d;transition:transform .6s cubic-bezier(.4,0,.2,1);cursor:pointer}.flashcard.flipped{transform:rotateY(180deg)}.flashcard-front,.flashcard-back{position:absolute;top:0;right:0;bottom:0;left:0;backface-visibility:hidden;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--space-8);border-radius:var(--radius-2xl);text-align:center;border:1px solid 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