:root{--paper: #f6f7fb;--ink: #282e3e;--muted: #646f90;--card: #ffffff;--line: #edeff4;--accent: #4255ff;--accent-dark: #3b4bde;--pine: #18ae79;--gold: #ffcd1f;--wrong: #ff725b;--learn: #7c5cff;--test: #0a9c7d;--shadow: 0 16px 40px rgba(40, 46, 62, .08)}*{box-sizing:border-box}html,body,#root{min-height:100%}body{margin:0;color:var(--ink);background:radial-gradient(900px 420px at 8% -10%,#e8ebff 0%,transparent 55%),radial-gradient(700px 360px at 100% 0%,#e7f8f2 0%,transparent 50%),var(--paper);font-family:DM Sans,system-ui,sans-serif}h1,h2,h3{font-family:DM Sans,system-ui,sans-serif;font-weight:700;letter-spacing:-.03em;margin:0}button,input,textarea,select{font:inherit}a{color:inherit;text-decoration:none}.shell{max-width:1080px;margin:0 auto;padding:28px 20px 80px}.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:28px}.brand{display:flex;align-items:baseline;gap:10px}.brand strong{font-size:28px;color:var(--accent)}.brand 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