:root{--bg:#0f1117;--bg-elevated:#1a1d28;--bg-hover:#232735;--border:#2d3142;--text:#e8eaed;--text-muted:#9aa0ab;--accent:#4285f4;--accent-hover:#5a95f5;--ok:#4caf7d;--error:#ef6a6a;color-scheme:dark}*{box-sizing:border-box}body,html{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Pretendard,Noto Sans KR,system-ui,sans-serif;font-size:15px;line-height:1.6}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}button{font-family:inherit}.container{max-width:960px;margin:0 auto;padding:0 20px}.btn-primary{background:var(--accent);color:#fff;border:none;border-radius:8px;padding:10px 18px;font-size:14px;font-weight:600;cursor:pointer;transition:background .15s}.btn-primary:hover:not(:disabled){background:var(--accent-hover)}.btn-primary:disabled{opacity:.5;cursor:not-allowed}.btn-ghost{background:transparent;border:1px solid var(--border);color:var(--text);border-radius:8px;padding:8px 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6px}