/* 主卡片 – 阳光黄调 */
        .card {
            max-width: 800px;
            width: 100%;
            background: #ffffff;
            border-radius: 40px;
            box-shadow: 0 20px 40px -12px rgba(202, 150, 20, 0.25),
                        0 8px 24px -6px rgba(250, 204, 21, 0.15);
            padding: 32px 24px 28px;
            transition: transform 0.2s ease;
            border: 1px solid rgba(253, 224, 71, 0.3);
        }

        /* 头部 */
        .header {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-bottom: 28px;
        }

        .header h1 {
            font-size: 26px;
            font-weight: 700;
            letter-spacing: -0.3px;
            background: linear-gradient(135deg, #b45309, #d97706);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .header h1::before {
            content: "⚡";
            background: none;
            -webkit-text-fill-color: #f59e0b;
            font-size: 28px;
        }

        .badge {
            background: #fef9c3;
            padding: 6px 14px;
            border-radius: 40px;
            font-size: 13px;
            font-weight: 600;
            color: #92400e;
            border: 1px solid #fde68a;
            box-shadow: 0 2px 4px rgba(251, 191, 36, 0.1);
            white-space: nowrap;
        }

        /* 金额选择区 */
        .amount-section {
            margin-bottom: 28px;
        }

        .amount-label {
            font-size: 15px;
            font-weight: 500;
            color: #78350f;
            margin-bottom: 12px;
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .amount-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 10px;
            margin-bottom: 14px;
        }

        .amount-btn {
            background: #fffbeb;
            border: 1.5px solid #fde68a;
            border-radius: 20px;
            padding: 12px 0;
            font-size: 18px;
            font-weight: 600;
            color: #92400e;
            cursor: pointer;
            transition: all 0.15s ease;
            box-shadow: 0 2px 4px rgba(251, 191, 36, 0.05);
            text-align: center;
        }

        .amount-btn:active {
            transform: scale(0.94);
            background: #fef3c7;
            border-color: #fbbf24;
        }

        .amount-btn.selected {
            background: #fbbf24;
            border-color: #d97706;
            color: #7c2d12;
            box-shadow: 0 4px 10px rgba(251, 191, 36, 0.35);
            font-weight: 700;
        }

        .custom-amount {
            display: flex;
            align-items: center;
            background: #fffbeb;
            border: 1.5px solid #fde68a;
            border-radius: 30px;
            padding: 4px 4px 4px 18px;
            margin-top: 4px;
        }

        .custom-amount span {
            color: #a16207;
            font-weight: 500;
            font-size: 16px;
            margin-right: 4px;
        }

        .custom-amount input {
            flex: 1;
            border: none;
            background: transparent;
            padding: 12px 4px 12px 0;
            font-size: 18px;
            font-weight: 500;
            color: #78350f;
            outline: none;
            min-width: 0;
        }

        .custom-amount input::placeholder {
            color: #d4a373;
            font-weight: 400;
            font-size: 15px;
        }

        .custom-amount button {
            background: #fbbf24;
            border: none;
            border-radius: 30px;
            padding: 10px 20px;
            font-weight: 600;
            font-size: 15px;
            color: #7c2d12;
            cursor: pointer;
            transition: 0.1s ease;
            white-space: nowrap;
            box-shadow: 0 2px 6px rgba(251, 191, 36, 0.3);
        }

        .custom-amount button:active {
            background: #f59e0b;
            transform: scale(0.96);
        }

        /* 二维码区域 – 黄色光晕 */
        .qr-wrapper {
            background: #fef9c3;
            border-radius: 32px;
            padding: 20px;
            margin: 20px 0 18px;
            border: 1px solid #fde68a;
            box-shadow: inset 0 2px 8px rgba(251, 191, 36, 0.08), 0 8px 20px -8px rgba(202, 138, 4, 0.2);
            display: flex;
            flex-direction: column;
            align-items: center;
        }

        .qr-container {
            background: white;
            border-radius: 24px;
            padding: 16px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.02);
            width: 100%;
            margin: 0 auto;
        }

        .qr-container svg {
            display: block;
            width: 100%;
            height: auto;
            aspect-ratio: 1/1;
        }

        .qr-hint {
            margin-top: 14px;
            font-size: 14px;
            color: #92400e;
            background: rgba(255,255,240,0.6);
            padding: 6px 18px;
            border-radius: 40px;
            border: 1px solid #fde68a;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            font-weight: 500;
            backdrop-filter: blur(2px);
        }

        .qr-hint::before {
            content: "📱";
            font-size: 16px;
        }

        /* 确认充值按钮 */
        .confirm-btn {
            width: 100%;
            background: linear-gradient(135deg, #f59e0b, #d97706);
            border: none;
            border-radius: 40px;
            padding: 18px 0;
            font-size: 20px;
            font-weight: 700;
            color: #fff7ed;
            letter-spacing: 0.5px;
            cursor: pointer;
            transition: all 0.15s ease;
            box-shadow: 0 8px 18px -6px #d97706, 0 2px 6px rgba(245, 158, 11, 0.2);
            margin-top: 6px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
        }

        .confirm-btn:active {
            transform: scale(0.97);
            box-shadow: 0 4px 10px -4px #b45309;
            background: linear-gradient(135deg, #d97706, #b45309);
        }

        .confirm-btn::before {
            content: "✨";
            font-size: 22px;
        }

        /* 底部小字 */
        .footer-note {
            display: flex;
            justify-content: space-between;
            margin-top: 20px;
            font-size: 13px;
            color: #a16207;
            padding: 0 4px;
            opacity: 0.8;
        }

        .footer-note span:first-child::before {
            content: "🛡️ ";
        }

        .footer-note span:last-child {
            font-weight: 500;
        }

        /* 金额显示 */
        .selected-display {
            text-align: center;
            margin: 4px 0 10px;
            font-size: 15px;
            color: #78350f;
            background: #fffbeb;
            padding: 6px 12px;
            border-radius: 40px;
            display: inline-block;
            border: 1px solid #fde68a;
        }

        .flex-center {
            display: flex;
            justify-content: center;
        }

        /* 响应式 */
        @media (max-width: 400px) {
            .card { padding: 24px 16px; }
            .amount-grid { gap: 8px; }
            .amount-btn { font-size: 16px; padding: 10px 0; }
            .header h1 { font-size: 22px; }
        }