* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Montserrat', sans-serif;
        }

        body {
            background-color: #1a1a2e;
            color: #fff;
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh;
        }

        .container {
            background-color: #2a2a4e;
            border-radius: 10px;
            padding: 40px;
            text-align: center;
            max-width: 600px;
            width: 90%;
            box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
            border: 2px solid #f8c537;
            position: relative;
            overflow: hidden;
        }

        .header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 30px;
        }

        .back-button {
            color: #f8c537;
            font-size: 1.5rem;
            cursor: pointer;
            transition: transform 0.3s;
        }

        .back-button:hover {
            transform: translateX(-5px);
        }

        .logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: #f8c537;
            text-shadow: 0 0 10px rgba(248, 197, 55, 0.5);
            flex-grow: 1;
            text-align: center;
        }

        h1 {
            color: #f8c537;
            margin-bottom: 20px;
            font-size: 1.8rem;
            text-shadow: 0 0 10px rgba(248, 197, 55, 0.5);
        }

        .payment-methods {
            margin: 30px 0;
        }

        .method {
            background-color: #3a3a5e;
            padding: 15px;
            border-radius: 8px;
            margin-bottom: 15px;
            display: flex;
            align-items: center;
            cursor: pointer;
            transition: all 0.3s;
            border-left: 4px solid #444466;
        }

        .method:hover {
            transform: translateX(5px);
            border-left-color: #f8c537;
        }

        .method.selected {
            border-left-color: #f8c537;
            background: linear-gradient(to right, #3a3a5e, #4a3a4e);
        }

        .method-icon {
            font-size: 1.8rem;
            margin-right: 15px;
            color: #f8c537;
            width: 40px;
            text-align: center;
        }

        .method-info {
            flex-grow: 1;
            text-align: left;
        }

        .method-name {
            font-weight: bold;
            margin-bottom: 5px;
        }

        .method-desc {
            font-size: 0.9rem;
            color: #aaa;
        }

        .custom-amount {
            margin: 25px 0;
        }

        .custom-amount input {
            width: 100%;
            padding: 15px;
            border-radius: 8px;
            border: 2px solid #f8c537;
            background-color: #3a3a5e;
            color: white;
            font-size: 1.2rem;
            text-align: center;
            margin-bottom: 15px;
        }

        .custom-amount input::placeholder {
            color: #aaa;
        }

        .amount-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 15px;
            margin: 30px 0;
        }

        .amount-option {
            background-color: #3a3a5e;
            padding: 15px;
            border-radius: 8px;
            border: 2px solid #444466;
            cursor: pointer;
            transition: all 0.3s;
            font-weight: bold;
        }

        .amount-option:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(248, 197, 55, 0.2);
            border-color: #f8c537;
        }

        .amount-option.selected {
            background-color: #f8c537;
            color: #1a1a2e;
            border-color: #f8c537;
        }

        .confirm-button {
            background: linear-gradient(135deg, #f8c537, #f8a537);
            color: #1a1a2e;
            border: none;
            padding: 15px 30px;
            border-radius: 8px;
            font-size: 1.2rem;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s;
            width: 100%;
            margin-top: 20px;
        }

        .confirm-button:hover {
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(248, 197, 55, 0.4);
        }

        .info-text {
            margin-top: 30px;
            font-size: 0.9rem;
            color: #aaa;
        }

        @media (max-width: 768px) {
            .container {
                padding: 30px 20px;
            }
            
            .amount-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            
            .logo {
                font-size: 1.5rem;
            }
        }