:root{color-scheme:light;--brand:#f97316;--brand-dark:#ea580c;--text:#111827;--muted:#6b7280;--border:#e5e7eb;--bg:#f9fafb;--error:#b91c1c;--success:#047857}*{box-sizing:border-box}body,html{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;font-size:16px;line-height:1.5}main{max-width:480px;margin:0 auto;padding:48px 20px}.card{background:#fff;border:1px solid var(--border);border-radius:12px;padding:28px}h1{font-size:24px;font-weight:700;margin:0 0 6px}p.subtitle{color:var(--muted);margin:0 0 24px;font-size:14px}label{display:block;font-size:13px;font-weight:600;margin:16px 0 6px}input{width:100%;padding:12px 14px;font-size:15px;border:1px solid var(--border);border-radius:8px;background:#fff;font-family:ui-monospace,SFMono-Regular,Menlo,monospace}input:focus{outline:2px solid var(--brand);outline-offset:-1px;border-color:var(--brand)}button[type=submit]{width:100%;margin-top:20px;padding:12px 16px;background:var(--brand);color:#fff;font-size:15px;font-weight:600;border:0;border-radius:8px;cursor:pointer}button[type=submit]:hover:not(:disabled){background:var(--brand-dark)}button[type=submit]:disabled{opacity:.6;cursor:not-allowed}.help-wrap{position:relative;display:inline-block;margin-left:6px;vertical-align:middle}.help-btn{width:16px;height:16px;padding:0;border:0;border-radius:50%;background:var(--border);color:#4b5563;font-size:11px;font-weight:700;line-height:1;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;font-family:inherit}.help-btn:hover{background:#d1d5db}.help-tip{position:absolute;top:100%;left:50%;transform:translateX(-50%);margin-top:8px;background:#111827;color:#fff;font-size:12px;font-weight:400;padding:8px 10px;border-radius:6px;width:240px;z-index:10;line-height:1.4;pointer-events:none}.msg{margin-top:16px;padding:10px 12px;border-radius:8px;font-size:14px}.msg.error{background:#fef2f2;color:var(--error);border:1px solid #fecaca}.msg.success{background:#ecfdf5;color:var(--success);border:1px solid #a7f3d0}