html,
        body {
            margin: 0;
        }

        /* Fundo com gradiente diagonal FMBadminton */
        .page-bg {
            background: linear-gradient(135deg, #8B0000 0%, #C8102E 35%, #1A5C4A 100%);
            position: relative;
            overflow: hidden;
        }

        /* Círculos decorativos de fundo */
        .deco-circle {
            position: absolute;
            border-radius: 50%;
            opacity: 0.08;
            background: #F5C400;
        }

        /* Volante SVG animado */
        .shuttle-wrap {
            animation: floatY 3s ease-in-out infinite;
            filter: drop-shadow(0 8px 24px rgba(0, 0, 0, 0.35));
        }

        /* Linha decorativa amarela */
        .yellow-line {
            width: 60px;
            height: 4px;
            background: #F5C400;
            border-radius: 2px;
            margin: 0 auto 1.5rem;
        }

        /* Card central */
        .error-card {
            animation: fadeIn 0.7s ease forwards;
            backdrop-filter: blur(12px);
            background: rgba(255, 255, 255, 0.07);
            border: 1px solid rgba(255, 255, 255, 0.15);
        }

        /* Botão primário */
        .btn-primary {
            background: #F5C400;
            color: #111;
            font-weight: 700;
            border-radius: 9999px;
            padding: 0.75rem 2rem;
            transition: filter 0.2s, transform 0.15s;
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
        }

        .btn-primary:hover {
            filter: brightness(1.1);
            transform: translateY(-2px);
        }

        /* Botão secundário */
        .btn-secondary {
            border: 2px solid rgba(255, 255, 255, 0.5);
            color: #fff;
            font-weight: 600;
            border-radius: 9999px;
            padding: 0.7rem 1.8rem;
            transition: background 0.2s, transform 0.15s;
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
        }

        .btn-secondary:hover {
            background: rgba(255, 255, 255, 0.12);
            transform: translateY(-2px);
        }