body { margin: 0; background: #f1f5f9; color: #172033; font-family: Arial, sans-serif; }
        .error-shell { min-height: 100vh; display: grid; place-items: center; padding: 24px; box-sizing: border-box; }
        .error-panel { width: min(100%, 560px); background: #fff; border: 1px solid #d7e1ed; border-radius: 8px; box-shadow: 0 12px 32px rgba(15, 23, 42, .12); padding: 32px; }
        .error-kicker { margin: 0 0 10px; color: #087f76; font-size: 13px; font-weight: 700; text-transform: uppercase; }
        h1 { margin: 0; font-size: 28px; }
        p { color: #455b7a; font-size: 16px; line-height: 1.55; }
        .error-code { display: inline-block; margin-top: 8px; padding: 5px 9px; border-radius: 4px; background: #e6f4ff; color: #075985; font-family: monospace; font-size: 13px; }
        .error-actions { display: flex; gap: 12px; margin-top: 26px; }
        button { border: 0; border-radius: 6px; background: #087f76; color: #fff; cursor: pointer; font-size: 16px; font-weight: 700; padding: 11px 18px; }
        button:hover { background: #06665f; }