:root{--bg-dark: #0f172a;--bg-card: #1e293b;--text-primary: #f8fafc;--text-secondary: #94a3b8;--accent-primary: #8b5cf6;--accent-hover: #7c3aed;--accent-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);--success: #22c55e;--error: #ef4444;--border: #334155;--font-family: "Inter", system-ui, sans-serif}body{margin:0;padding:0;background-color:var(--bg-dark);color:var(--text-primary);font-family:var(--font-family);-webkit-font-smoothing:antialiased;min-height:100vh}#root{max-width:1200px;margin:0 auto;padding:2rem;text-align:center}button{cursor:pointer;border:none;font-family:inherit;transition:all .2s ease}.btn-primary{background:var(--accent-gradient);color:#fff;padding:.75rem 1.5rem;border-radius:.5rem;font-weight:600;box-shadow:0 4px 6px -1px #0000001a}.btn-primary:hover{opacity:.9;transform:translateY(-1px)}.btn-secondary{background:var(--bg-card);color:var(--text-primary);border:1px solid var(--border);padding:.75rem 1.5rem;border-radius:.5rem;font-weight:500}.btn-secondary:hover{background:#334155}.mobile-only{display:none!important}.desktop-only{display:flex!important}@media(max-width:640px){.mobile-only{display:flex!important}.desktop-only{display:none!important}}.no-scrollbar::-webkit-scrollbar{display:none!important}.no-scrollbar{-ms-overflow-style:none!important;scrollbar-width:none!important}.input-area{width:100%;min-height:300px;background:var(--bg-card);border:1px solid var(--border);border-radius:.75rem;color:var(--text-primary);padding:1rem;font-family:monospace;font-size:.9rem;resize:vertical}.input-area:focus{outline:2px solid var(--accent-primary);border-color:transparent}.flashcard-container{perspective:1000px;width:100%;max-width:600px;height:350px;margin:2rem auto;cursor:pointer}.flashcard-inner{position:relative;width:100%;height:100%;text-align:center;transition:transform .6s;transform-style:preserve-3d}.flashcard-container.flipped .flashcard-inner{transform:rotateY(180deg)}.flashcard-front,.flashcard-back{position:absolute;width:100%;height:100%;-webkit-backface-visibility:hidden;backface-visibility:hidden;border-radius:1rem;background:var(--bg-card);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;padding:2rem;box-sizing:border-box;box-shadow:0 10px 15px -3px #0000001a}.flashcard-front{font-size:2rem;font-weight:700;color:var(--text-primary)}.flashcard-back{transform:rotateY(180deg);background:linear-gradient(135deg,#1e293b,#0f172a);font-size:1.25rem;line-height:1.6}.match-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:1rem;margin-top:2rem}.match-card{background:var(--bg-card);border:1px solid var(--border);border-radius:.5rem;padding:1rem;min-height:100px;display:flex;align-items:center;justify-content:center;font-size:.9rem;cursor:pointer;transition:all .2s;-webkit-user-select:none;user-select:none}.match-card:hover{background:#334155;transform:scale(1.02)}.match-card.selected{border-color:var(--accent-primary);background:#8b5cf61a;box-shadow:0 0 0 2px var(--accent-primary)}.match-card.matched{opacity:0;pointer-events:none;transform:scale(.8)}@media(max-width:640px){.match-card.matched{display:none!important}}.match-card.errors{border-color:var(--error);background:#ef44441a;animation:shake .5s}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}.tabs{display:flex;justify-content:center;gap:1rem;margin-bottom:2rem;border-bottom:1px solid var(--border);padding-bottom:1rem}.tab{display:flex;align-items:center;gap:.5rem;background:transparent;color:var(--text-secondary);font-size:1rem;padding:.5rem 1rem;border-radius:.5rem}@media(max-width:640px){.app-main{padding-bottom:80px!important}.tabs{position:fixed;bottom:0;left:0;right:0;margin-bottom:0;padding:.5rem 0;background:var(--bg-card);border-top:1px solid var(--border);border-bottom:none;z-index:100;justify-content:space-evenly;gap:0}.tab{flex-direction:column;padding:.25rem .5rem;font-size:.7rem;border:none;border-radius:0;gap:.25rem}.tab.active{color:var(--accent-primary);background:transparent}}.tab.active{background:var(--bg-card);color:var(--text-primary);font-weight:600}.mobile-only-tab{display:none!important}.quiz-options-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}.quiz-option{display:block;width:100%;text-align:left;padding:1rem;background:var(--bg-card);border:1px solid var(--border);border-radius:.5rem;color:var(--text-primary);word-break:break-word;overflow-wrap:break-word;height:100%}.quiz-option:hover{background:#334155}.quiz-option.correct{border-color:var(--success);background:#22c55e1a}.quiz-option.wrong{border-color:var(--error);background:#ef44441a}.markdown-content{text-align:left}.markdown-content h1,.markdown-content h2,.markdown-content h3{margin-top:1rem;margin-bottom:.5rem;color:var(--accent-primary)}.markdown-content p{margin-bottom:.8rem}.markdown-content ul,.markdown-content ol{margin-left:1.5rem;margin-bottom:1rem}.markdown-content li{margin-bottom:.25rem}.markdown-content strong{color:var(--success)}.app-header{margin-bottom:1.5rem;margin-top:1rem;position:relative;text-align:center}.header-github{position:absolute;top:0;right:0;display:flex;align-items:center;gap:.3rem;text-decoration:none;color:#fff;padding:.3rem .6rem;font-size:.6rem}.header-back{position:absolute;top:0;left:0;display:flex;align-items:center;gap:.3rem;color:#fff;padding:.3rem .6rem;font-size:.6rem}@media(max-width:640px){.line-numbers{display:none!important}.app-header{margin-bottom:.5rem;display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:.5rem;padding-top:2rem}.header-github,.header-back{display:none!important}.btn-primary{padding:.5rem 1rem;font-size:.9rem}.input-area{font-size:16px}.action-bar{justify-content:space-between;width:100%;flex-wrap:nowrap!important;gap:.25rem!important}.help-btn .btn-text{display:none}.action-btn{padding:.3rem .5rem!important}.action-btn .btn-text{font-size:.7rem}.ai-toggle{padding:.3rem .5rem!important;font-size:.7rem!important}.ai-label{font-size:.7rem!important}#root{padding:0!important}.app-main{padding:.25rem .5rem!important}.input-container{padding:0 .5rem!important}}.action-bar{display:flex;gap:.5rem;flex-wrap:wrap;justify-content:flex-end;width:100%}.action-btn{padding:.375rem .75rem;display:flex;align-items:center;gap:.375rem;color:var(--text-primary)}.action-btn svg{color:#fff}.btn-text{font-size:.75rem}.ai-toggle{display:flex;align-items:center;gap:.375rem;cursor:pointer;background:var(--bg-card);padding:.375rem .75rem;border-radius:.5rem;border:1px solid var(--border);transition:all .2s;white-space:nowrap}.ai-toggle.active{background:#8b5cf633;border-color:var(--accent-primary)}.ai-toggle input{accent-color:var(--accent-primary)}.ai-icon{color:var(--text-secondary)}.ai-toggle.active .ai-icon{color:var(--accent-primary)}.ai-label{color:var(--text-secondary);font-weight:500;font-size:.75rem}.ai-toggle.active .ai-label{color:var(--accent-primary)}.app-main{min-height:100vh;padding:1rem;max-width:1200px;margin:0 auto}.input-container{max-width:800px;margin:0 auto;padding:0 1rem}.help-btn{margin-right:auto}@media(max-width:640px){.app-main{padding-bottom:80px!important}.tabs{position:fixed;bottom:0;left:0;right:0;margin-bottom:0;padding:.5rem 0;background:var(--bg-card);border-top:1px solid var(--border);border-bottom:none;z-index:100;justify-content:space-evenly;gap:0}.tab{flex-direction:column;padding:.25rem .5rem;font-size:.7rem;border:none;border-radius:0;gap:.25rem}.tab.active{color:var(--accent-primary)!important;background:transparent!important}.mobile-only-tab{display:flex!important}}.quiz-score{display:flex;gap:1rem;font-size:.9rem;font-weight:600}.score-item.correct{color:var(--success)}.score-item.wrong{color:var(--error)}.score-separator{display:none;color:var(--text-secondary);font-weight:400}@media(max-width:640px){.quiz-score{gap:.5rem}.score-label{display:none}.score-separator{display:inline}}.recall-card{background:var(--bg-card);border:1px solid var(--border);border-radius:1rem;padding:2rem;margin-bottom:2rem;min-height:200px;display:flex;flex-direction:column;justify-content:center;box-shadow:0 4px 6px -1px #0000001a}@media(max-width:640px){.recall-card{min-height:150px;padding:1.5rem;margin-bottom:1.5rem}}.quiz-card{position:relative;width:100%;min-height:250px;margin-bottom:2rem;height:auto;font-size:1.5rem;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;white-space:pre-wrap;word-break:break-word;padding:2.5rem;box-sizing:border-box;overflow-y:auto;max-height:500px;background:var(--bg-card);border:1px solid var(--border);border-radius:1rem;box-shadow:0 10px 15px -3px #0000001a;color:var(--text-primary)}.quiz-option{font-size:1rem}@media(max-width:640px){.quiz-mode-def-to-term .quiz-option{font-size:1.1rem!important}.quiz-mode-term-to-def .quiz-card{font-size:1.6rem!important;min-height:120px!important;padding:1rem!important;font-weight:700}.quiz-mode-term-to-def .quiz-option{font-size:1rem!important;line-height:1.4}.quiz-options-grid{grid-template-columns:1fr}.header-tagline{display:none}.app-header{padding-top:.1rem!important;margin-bottom:.25rem!important}.footer-github{display:flex!important;margin:1rem auto 0;width:fit-content}}.footer{margin-top:4rem;padding:2rem 0;color:var(--text-secondary);font-size:.8rem;text-align:center;border-top:1px solid var(--border)}.footer-github{display:none;align-items:center;gap:.3rem;text-decoration:none;color:#fff!important;padding:.5rem 1rem;font-size:.8rem}@media(min-width:641px){.footer-github{display:none!important}}