@import"https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap";:root{--background: 0 0% 100%;--foreground: 222.2 84% 4.9%;--card: 0 0% 100%;--card-foreground: 222.2 84% 4.9%;--popover: 0 0% 100%;--popover-foreground: 222.2 84% 4.9%;--primary: 221.2 83.2% 53.3%;--primary-foreground: 210 40% 98%;--secondary: 210 40% 96%;--secondary-foreground: 222.2 84% 4.9%;--muted: 210 40% 96%;--muted-foreground: 215.4 16.3% 46.9%;--accent: 210 40% 96%;--accent-foreground: 222.2 84% 4.9%;--destructive: 0 84.2% 60.2%;--destructive-foreground: 210 40% 98%;--border: 214.3 31.8% 91.4%;--input: 214.3 31.8% 91.4%;--ring: 221.2 83.2% 53.3%}.dark{--background: 222.2 84% 4.9%;--foreground: 210 40% 98%;--card: 222.2 84% 4.9%;--card-foreground: 210 40% 98%;--popover: 222.2 84% 4.9%;--popover-foreground: 210 40% 98%;--primary: 217.2 91.2% 59.8%;--primary-foreground: 222.2 84% 4.9%;--secondary: 217.2 32.6% 17.5%;--secondary-foreground: 210 40% 98%;--muted: 217.2 32.6% 17.5%;--muted-foreground: 215 20.2% 65.1%;--accent: 217.2 32.6% 17.5%;--accent-foreground: 210 40% 98%;--destructive: 0 62.8% 30.6%;--destructive-foreground: 210 40% 98%;--border: 217.2 32.6% 17.5%;--input: 217.2 32.6% 17.5%;--ring: 224.3 76.3% 94.1%}*{border-color:hsl(var(--border))}body{background-color:hsl(var(--background));color:hsl(var(--foreground));font-family:Inter,sans-serif;margin:0;padding:0;min-height:100vh}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:hsl(var(--secondary))}::-webkit-scrollbar-thumb{background:hsl(var(--muted-foreground));border-radius:3px}::-webkit-scrollbar-thumb:hover{background:hsl(var(--foreground))}.progress-bar{transition:width .3s ease-in-out}.difficulty-easy{background-color:#10b981;color:#fff}.difficulty-medium{background-color:#f59e0b;color:#fff}.difficulty-hard{background-color:#ef4444;color:#fff}@keyframes gradient-x{0%,to{background-size:200% 200%;background-position:left center}50%{background-size:200% 200%;background-position:right center}}.animate-gradient-x{animation:gradient-x 3s ease infinite}.transition-all{transition:all .3s cubic-bezier(.4,0,.2,1)}.hover-lift:hover{transform:translateY(-4px)}.glass{background:#ffffff1a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.2)}@keyframes shimmer{0%{background-position:-200% 0}to{background-position:200% 0}}.animate-shimmer{animation:shimmer 2s infinite linear}.scrollbar-thin{scrollbar-width:thin;scrollbar-color:#3f3f46 #18181b}.scrollbar-thin::-webkit-scrollbar{width:6px}.scrollbar-thin::-webkit-scrollbar-track{background:#18181b;border-radius:3px}.scrollbar-thin::-webkit-scrollbar-thumb{background:#3f3f46;border-radius:3px;transition:background-color .2s ease}.scrollbar-thin::-webkit-scrollbar-thumb:hover{background:#52525b}.sticky-sidebar{position:sticky;top:0;height:100vh;overflow:hidden}.focus-visible:focus-visible{outline:2px solid #3b82f6;outline-offset:2px}.topic-content{transition:max-height .5s ease-in-out}.topic-content.expanded{max-height:none!important}.topic-content.collapsed{max-height:0!important;overflow:hidden}