:root {
        --bg-color: #f8fafc;
        --card-bg: #ffffff;
        --border-color: #e2e8f0;
        --text-primary: #0f172a;
        --text-secondary: #475569;
        --accent-blue: #2563eb;
        --accent-glow: rgba(37,99,235,0.14);
        --success-color: #10b981;
        --danger-color: #ef4444;
        --radius: 18px;
    }
    body { background: var(--bg-color); color: var(--text-primary); font-family: 'Plus Jakarta Sans', sans-serif; min-height: 100vh; margin: 0; }
    .stack-container { max-width: 490px; margin: 0 auto; padding: 1.5rem 1rem 4rem; display: flex; flex-direction: column; gap: 1.25rem; }
    .stack-card { background: var(--card-bg); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 1.6rem; box-shadow: 0 4px 20px rgba(0,0,0,0.03); }
    .stock-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1.25rem; }
    .stock-label { font-weight: 800; font-size: 1.05rem; }
    .stock-num { background: #dcfce7; color: #15803d; padding: .4rem .85rem; border-radius: 9999px; font-weight: 900; font-size: .85rem; }
    .stock-zero { background: #fee2e2; color: #b91c1c; }
    .qty-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: .75rem; margin-bottom: 1rem; }
    .qty-btn { background: #f8fafc; border: 1.5px solid #e2e8f0; border-radius: 14px; padding: 1rem .5rem; text-align: center; cursor: pointer; transition: all .2s ease; color: var(--text-primary); }
    .qty-btn:hover { border-color: var(--accent-blue); background: #eff6ff; }
    .qty-btn.active { background: linear-gradient(135deg, #2563eb, #1d4ed8); border-color: #2563eb; color: white; transform: translateY(-2px); box-shadow: 0 8px 18px rgba(37,99,235,0.28); }
    .qty-btn h5 { font-size: 1.15rem; font-weight: 900; margin: 0; }
    .qty-btn small { font-size: .85rem; font-weight: 800; opacity: .88; }
    .custom-input { width: 100%; border: 1.5px solid #e2e8f0; background: #f8fafc; border-radius: 14px; padding: .85rem 1rem; font-weight: 800; color: var(--text-primary); text-align: center; font-size: 1rem; transition: .2s; }
    .custom-input:focus { outline: none; border-color: var(--accent-blue); background: #fff; box-shadow: 0 0 0 3px rgba(37,99,235,0.15); }
    .btn-main { width: 100%; background: linear-gradient(135deg, #2563eb, #1e40af); color: white; border: none; padding: 1.05rem; border-radius: 14px; font-size: 1.1rem; font-weight: 800; transition: all .2s; margin-top: 1.1rem; box-shadow: 0 10px 24px rgba(37,99,235,0.25); cursor: pointer; display: flex; align-items: center; justify-content: center; gap: 8px; }
    .btn-main:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(37,99,235,0.35); }
    .feature-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: .75rem; text-align: center; }
    .f-item { padding: 1rem .5rem; background: var(--card-bg); border: 1px solid var(--border-color); border-radius: 14px; }
    .f-icon { color: var(--accent-blue); font-size: 1.3rem; margin-bottom: .3rem; }
    .f-title { font-weight: 800; font-size: .85rem; }
    .f-sub { font-size: .75rem; color: var(--text-secondary); }

    /* REAL FINTECH PAYMENT GATEWAY MODAL */
    .pg-modal-overlay {
        position: fixed; inset: 0; background: rgba(15, 23, 42, 0.78); backdrop-filter: blur(8px);
        z-index: 99999; display: flex; align-items: center; justify-content: center; padding: 14px; overflow-y: auto;
    }
    .pg-modal-shell {
        width: 100%; max-width: 440px; background: #ffffff; border-radius: 22px;
        box-shadow: 0 25px 60px rgba(0,0,0,0.35); border: 1px solid #e2e8f0; overflow: hidden;
        animation: pgSlideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    }
    @keyframes pgSlideUp { from { opacity: 0; transform: translateY(20px) scale(0.96); } to { opacity: 1; transform: translateY(0) scale(1); } }
    
    .pg-head {
        background: #ffffff; padding: 18px 20px; border-bottom: 1px solid #f1f5f9;
        display: flex; align-items: center; justify-content: space-between;
    }
    .pg-merchant { display: flex; align-items: center; gap: 12px; }
    .pg-merchant-logo { width: 42px; height: 42px; border-radius: 12px; object-fit: contain; background: #f8fafc; border: 1px solid #e2e8f0; padding: 3px; }
    .pg-merchant-name { font-size: 15px; font-weight: 900; color: #0f172a; margin: 0; line-height: 1.2; }
    .pg-merchant-badge { display: inline-flex; align-items: center; gap: 4px; font-size: 11px; font-weight: 800; color: #16a34a; }
    .pg-close { background: #f1f5f9; border: 0; width: 30px; height: 30px; border-radius: 50%; color: #64748b; font-size: 16px; cursor: pointer; display: grid; place-items: center; transition: .15s; }
    .pg-close:hover { background: #fee2e2; color: #ef4444; }

    .pg-amount-strip {
        background: #f8fafc; border-bottom: 1px solid #e2e8f0; padding: 12px 20px;
        display: flex; align-items: center; justify-content: space-between;
    }
    .pg-amount-strip span { font-size: 12px; font-weight: 700; color: #64748b; }
    .pg-amount-strip strong { font-size: 20px; font-weight: 900; color: #0f172a; }

    .pg-body { padding: 20px; text-align: center; }
    .pg-qr-wrapper {
        width: 190px; height: 190px; margin: 0 auto 12px; padding: 8px;
        background: #ffffff; border: 2px solid #e2e8f0; border-radius: 16px;
        box-shadow: 0 8px 20px rgba(0,0,0,0.04); position: relative;
    }
    .pg-qr-wrapper img { width: 100%; height: 100%; object-fit: contain; border-radius: 10px; }
    
    .pg-timer-row {
        display: inline-flex; align-items: center; gap: 6px; font-size: 12px; font-weight: 800;
        color: #d97706; background: #fffbeb; border: 1px solid #fde68a; padding: 4px 12px; border-radius: 999px; margin-bottom: 14px;
    }
    .pg-upi-apps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-bottom: 16px; }
    .pg-app-item {
        background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 11px; padding: 8px 4px;
        text-decoration: none; display: flex; flex-direction: column; align-items: center; gap: 3px;
        font-size: 10px; font-weight: 800; color: #334155; transition: .15s;
    }
    .pg-app-item:hover { background: #eff6ff; border-color: #93c5fd; color: #1d4ed8; }
    .pg-app-item img { width: 22px; height: 22px; border-radius: 4px; object-fit: contain; }

    .pg-utr-box {
        background: #f8fafc; border: 1.5px dashed #cbd5e1; border-radius: 14px; padding: 12px 14px; text-align: left;
    }
    .pg-utr-box label { font-size: 11px; font-weight: 800; color: #475569; display: block; margin-bottom: 6px; }
    .pg-utr-flex { display: flex; gap: 6px; }
    .pg-utr-input {
        flex: 1; border: 1px solid #cbd5e1; border-radius: 10px; padding: 8px 12px;
        font-family: 'JetBrains Mono', monospace; font-size: 12px; font-weight: 700; color: #0f172a;
    }
    .pg-utr-btn {
        background: #2563eb; color: #fff; border: 0; border-radius: 10px; padding: 0 14px;
        font-size: 12px; font-weight: 800; cursor: pointer; transition: .15s;
    }
    .pg-utr-btn:hover { background: #1d4ed8; }
    .pg-foot-secure { margin-top: 14px; font-size: 11px; font-weight: 700; color: #94a3b8; display: flex; align-items: center; justify-content: center; gap: 6px; }