:root{--font-main: "Inter", system-ui, -apple-system, sans-serif;--color-bg: #0f172a;--color-surface: #1e293b;--color-text-primary: #f8fafc;--color-text-secondary: #94a3b8;--color-accent: #38bdf8;--color-accent-glow: rgba(56, 189, 248, .5);--color-success: #4ade80;--color-danger: #f87171;--radius-lg: 1rem;--radius-md: .5rem;--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .5), 0 4px 6px -2px rgba(0, 0, 0, .3);--shadow-glow: 0 0 20px var(--color-accent-glow)}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-main);background-color:var(--color-bg);color:var(--color-text-primary);line-height:1.6;min-height:100vh;display:flex;justify-content:center;align-items:center}#root{width:100%;max-width:600px;padding:2rem}h1,h2,h3{line-height:1.2;font-weight:700;letter-spacing:-.025em}h1{font-size:2.5rem;background:linear-gradient(to right,var(--color-text-primary),var(--color-accent));background-clip:text;-webkit-background-clip:text;-webkit-text-fill-color:transparent;margin-bottom:1rem}p{color:var(--color-text-secondary);margin-bottom:1.5rem}.intro-text{line-height:1.5;margin-bottom:1.25rem;text-align:left;max-width:460px;margin-left:auto;margin-right:auto}.card{background-color:var(--color-surface);border-radius:var(--radius-lg);padding:2rem;box-shadow:var(--shadow-lg);border:1px solid rgba(255,255,255,.05);text-align:center;transition:transform .2s ease}.btn{display:inline-flex;align-items:center;justify-content:center;padding:.75rem 1.5rem;border-radius:var(--radius-md);font-weight:600;font-size:1rem;cursor:pointer;transition:all .2s ease;border:none;outline:none;width:100%;margin-top:1rem}.btn-primary{background-color:var(--color-accent);color:var(--color-bg);box-shadow:0 4px 12px var(--color-accent-glow)}.btn-primary:hover{transform:translateY(-2px);box-shadow:0 6px 16px var(--color-accent-glow);filter:brightness(1.1)}.btn-secondary{background-color:transparent;border:1px solid var(--color-text-secondary);color:var(--color-text-primary)}.btn-secondary:hover{background-color:#ffffff0d}.btn-success{background-color:var(--color-success);color:var(--color-bg)}.btn-danger{background-color:var(--color-danger);color:var(--color-bg)}.word-display{font-size:3rem;font-weight:800;margin:3rem 0;color:var(--color-text-primary);text-transform:lowercase}.progress-bar{width:100%;height:6px;background-color:#ffffff1a;border-radius:3px;margin-bottom:2rem;overflow:hidden}.progress-fill{height:100%;background-color:var(--color-accent);transition:width .3s ease}.stats{display:flex;justify-content:space-between;font-size:.875rem;color:var(--color-text-secondary);margin-bottom:.5rem}.actions{display:grid;grid-template-columns:1fr 1fr;gap:1rem}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.animate-fade-in{animation:fadeIn .5s ease-out forwards}.practice-header{display:flex;align-items:center;gap:1rem;margin-bottom:1.5rem}.btn-text{background:none;border:none;color:var(--color-text-secondary);cursor:pointer;font-size:1rem;padding:.5rem}.btn-text:hover{color:var(--color-text-primary)}.word-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(100px,1fr));gap:.75rem;margin-top:2rem}.word-chip{background-color:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);padding:.75rem;color:var(--color-text-primary);cursor:pointer;transition:all .2s;font-size:.9rem}.word-chip:hover{background-color:var(--color-accent);color:var(--color-bg);transform:translateY(-2px)}.modal-overlay{position:fixed;inset:0;background-color:#000c;display:flex;justify-content:center;align-items:center;z-index:1000;padding:1rem;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px)}.modal-content{background-color:var(--color-surface);border-radius:var(--radius-lg);padding:2rem;width:100%;max-width:500px;max-height:80vh;overflow-y:auto;position:relative;border:1px solid rgba(255,255,255,.1);text-align:left}.close-btn{position:absolute;top:1rem;right:1rem;background:none;border:none;color:var(--color-text-secondary);font-size:1.5rem;cursor:pointer}.word-details{margin-top:1.5rem}.phonetic{color:var(--color-accent);font-family:monospace;margin-bottom:1rem}.meaning-block{margin-bottom:1.5rem}.meaning-block h3{font-size:1.1rem;color:var(--color-text-secondary);margin-bottom:.5rem;border-bottom:1px solid rgba(255,255,255,.1);padding-bottom:.25rem}.meaning-block ul{list-style-type:none;padding:0}.meaning-block li{margin-bottom:1rem}.definition{color:var(--color-text-primary);margin-bottom:.25rem}.example{color:var(--color-text-secondary);font-style:italic;font-size:.9rem;border-left:2px solid var(--color-accent);padding-left:.5rem}.modal-actions{margin-top:2rem;padding-top:1rem;border-top:1px solid rgba(255,255,255,.1)}