:root {
    --bg-color: #F8FAFC;
    --card-bg: #FFFFFF;
    --text-primary: #0F172A;
    --text-secondary: #64748B;
    --border-color: #E2E8F0;
    --primary-color: #0F172A;
    --primary-hover: #334155;
    
    /* Networks */
    --mpesa-color: #10B981;
    --orange-color: #F97316;
    --airtel-color: #EF4444;
    --africell-color: #8B5CF6;
    
    --radius-sm: 12px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
    --shadow-md: 0 10px 25px rgba(0,0,0,0.05);
    --shadow-lg: 0 20px 40px rgba(0,0,0,0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.checkout-container {
    width: 100%;
    max-width: 440px;
}

/* Header */
.checkout-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.merchant-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.merchant-logo-placeholder {
    width: 40px;
    height: 40px;
    background-color: var(--card-bg);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-sm);
    color: var(--text-primary);
}

.merchant-info h1 {
    font-family: 'Inter Tight', sans-serif;
    font-size: 18px;
    font-weight: 600;
}

.wikhapay-badge {
    font-size: 12px;
    color: var(--text-secondary);
}

.wikhapay-badge strong {
    color: var(--primary-color);
    font-weight: 700;
}

/* Card */
.payment-card {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    padding: 32px;
    box-shadow: var(--shadow-lg);
}

/* Amount Section */
.amount-section {
    text-align: center;
    margin-bottom: 32px;
}

.label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--text-secondary);
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.amount-display {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 8px;
    margin-bottom: 8px;
}

.amount {
    font-family: 'Inter Tight', sans-serif;
    font-size: 42px;
    font-weight: 700;
    color: var(--text-primary);
}

.currency {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-secondary);
}

.order-ref {
    font-size: 13px;
    color: var(--text-secondary);
}

/* Form Groups */
.form-group {
    margin-bottom: 24px;
}

/* Network Selector */
.network-selector {
    display: flex;
    justify-content: space-between;
    gap: 10px;
}

.network-option {
    cursor: pointer;
    flex: 1;
}

.network-option input {
    display: none;
}

.network-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 16px 8px;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    background-color: var(--bg-color);
    transition: all 0.2s ease;
}

.network-logo {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 16px;
    margin-bottom: 12px;
    border: 1.5px solid currentColor;
}

.network-card span {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
}

/* Network Colors & States */
.network-option.mpesa .network-logo { color: var(--mpesa-color); background: rgba(16, 185, 129, 0.1); }
.network-option.orange .network-logo { color: var(--orange-color); background: rgba(249, 115, 22, 0.1); }
.network-option.airtel .network-logo { color: var(--airtel-color); background: rgba(239, 68, 68, 0.1); }
.network-option.africell .network-logo { color: var(--africell-color); background: rgba(139, 92, 246, 0.1); }

.network-option.mpesa input:checked + .network-card {
    border-color: var(--mpesa-color);
    background: rgba(16, 185, 129, 0.05);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.15);
}
.network-option.orange input:checked + .network-card {
    border-color: var(--orange-color);
    background: rgba(249, 115, 22, 0.05);
    box-shadow: 0 4px 12px rgba(249, 115, 22, 0.15);
}
.network-option.airtel input:checked + .network-card {
    border-color: var(--airtel-color);
    background: rgba(239, 68, 68, 0.05);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.15);
}
.network-option.africell input:checked + .network-card {
    border-color: var(--africell-color);
    background: rgba(139, 92, 246, 0.05);
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.15);
}

.network-option input:checked + .network-card span {
    font-weight: 700;
    color: var(--text-primary);
}

/* Inputs */
.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.input-icon {
    position: absolute;
    left: 16px;
    color: var(--text-secondary);
}

.input-wrapper input {
    width: 100%;
    padding: 16px 16px 16px 48px;
    font-family: 'Inter', sans-serif;
    font-size: 16px;
    font-weight: 500;
    color: var(--text-primary);
    background-color: var(--bg-color);
    border: 1.5px solid var(--border-color);
    border-radius: var(--radius-md);
    outline: none;
    transition: all 0.2s ease;
}

.input-wrapper input::placeholder {
    color: #94A3B8;
}

.input-wrapper input:focus {
    border-color: var(--primary-color);
    background-color: var(--card-bg);
}

/* Submit Button */
.submit-btn {
    width: 100%;
    padding: 18px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 30px;
    font-family: 'Inter', sans-serif;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 10px;
    box-shadow: 0 4px 12px rgba(15, 23, 42, 0.2);
}

.submit-btn:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

.submit-btn:active {
    transform: translateY(1px);
}

.submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    background-color: var(--text-secondary);
}

.submit-btn.loading .btn-text {
    display: none;
}

.submit-btn.loading .spinner {
    display: block;
}

.spinner {
    display: none;
    animation: rotate 2s linear infinite;
    width: 24px;
    height: 24px;
}

.spinner .path {
    stroke: white;
    stroke-linecap: round;
    animation: dash 1.5s ease-in-out infinite;
}

@keyframes rotate {
    100% { transform: rotate(360deg); }
}

@keyframes dash {
    0% { stroke-dasharray: 1, 150; stroke-dashoffset: 0; }
    50% { stroke-dasharray: 90, 150; stroke-dashoffset: -35; }
    100% { stroke-dasharray: 90, 150; stroke-dashoffset: -124; }
}

/* Security Badge */
.security-badge {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-top: 24px;
    color: var(--text-secondary);
    font-size: 13px;
    font-weight: 500;
}

/* Overlay & Status */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(4px);
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    z-index: 100;
}

.overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.status-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    text-align: center;
    width: 90%;
    max-width: 360px;
    transform: translateY(20px);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.overlay.active .status-card {
    transform: translateY(0);
}

.status-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}

.status-icon.success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--mpesa-color);
}

.status-icon.error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--airtel-color);
}

.status-card h2 {
    font-family: 'Inter Tight', sans-serif;
    margin-bottom: 12px;
    font-size: 24px;
}

.status-card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.5;
}

.action-btn {
    width: 100%;
    padding: 14px;
    background-color: var(--bg-color);
    color: var(--text-primary);
    border: 1.5px solid var(--border-color);
    border-radius: 24px;
    font-family: 'Inter', sans-serif;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

    .action-btn:hover {
        background-color: #E2E8F0;
    }

    .status-icon.pending {
        background: rgba(15, 23, 42, 0.1);
        color: var(--primary-color);
    }
    
    .spin-animation {
        animation: spin 2s linear infinite;
    }
    
    @keyframes spin {
        0% { transform: rotate(0deg); }
        100% { transform: rotate(360deg); }
    }
    
    /* Mobile Adjustments */
    @media (max-width: 480px) {
        body {
            padding: 0;
            background-color: var(--card-bg);
            align-items: flex-start;
        }
    
    .checkout-container {
        max-width: 100%;
    }
    
    .payment-card {
        border-radius: 0;
        box-shadow: none;
        padding: 24px 20px;
    }
    
    .checkout-header {
        padding: 20px 20px 0;
        margin-bottom: 16px;
    }
}