:root {
    --primary-color: #2D1B69; /* Deep purple for titles and key elements */
    --secondary-color: #6a11cb; /* A slightly lighter purple for buttons */
    --text-color: #333; /* Dark grey for body text */
    --text-light: #666; /* Lighter grey for subtitles and less important text */
    --background-color: #f4f5f7; /* A very light grey for the page background */
    --card-background: #ffffff; /* White for all card elements */
    --border-color: #e8ebf1; /* Light border color */
    --success-color: #28a745;
    --error-color: #dc3545;
}

body {
    background-color: var(--background-color);
    color: var(--text-color);
}

#checkout-page .section-title {
    font-family: 'Playfair Display', serif;
    color: var(--primary-color);
    text-align: left;
    font-size: 2.5rem;
    margin-bottom: 2rem;
}

/* --- Main Grid Layout --- */
.checkout-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr; /* Give more space to the details column */
    gap: 40px;
    align-items: flex-start;
    padding: 40px 0;
}

.checkout-details-column {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.order-summary-column {
    position: sticky;
    top: 100px; /* Adjust sticky position */
}

/* --- Reusable Card Component Style --- */
.card {
    background: var(--card-background);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border-color);
    width: 100%;
    margin: 0;
}

.card {
    font-family: 'Playfair Display', serif;
    font-size: 1.6rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

/* --- Profile Display Card --- */
.profile-card {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    background: var(--card-background);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border-color);
}

.profile-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
    color: var(--primary-color);
    font-weight: 600;
}

.profile-card p {
    font-size: 0.95rem;
    color: var(--text-light);
    margin: 0;
}

/* --- Address Section --- */
.saved-address p {
    margin: 4px 0;
    line-height: 1.6;
    color: var(--text-light);
}

.saved-address p:first-child {
    font-weight: 600;
    font-size: 1.05rem;
    color: var(--text-color);
}

#addressPrompt {
    color: var(--text-light);
    font-style: italic;
}

/* --- Payment Method Section --- */
.payment-options {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
}

.payment-button {
    padding: 1rem;
    border-radius: 8px;
    border: 2px solid var(--border-color);
    background: transparent;
    text-align: left;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.payment-button:hover,
.payment-button.active {
    border-color: var(--secondary-color);
    background-color: #f8f5ff; /* A very light purple */
    box-shadow: 0 2px 8px rgba(106, 17, 203, 0.1);
}

.payment-button strong {
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary-color);
}

.payment-button span {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-top: 4px;
}

/* --- Order Summary Card --- */
.cart-summary {
    background: var(--card-background);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border-color);
}

.summary-row {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    font-size: 0.95rem;
    color: var(--text-light);
}

.summary-row:not(:last-child) {
    border-bottom: 1px solid var(--border-color);
}

.summary-row.total {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary-color);
    padding-top: 1rem;
    border-top: 2px solid #ddd;
    margin-top: 1rem;
}

/* --- Forms & Buttons (General) --- */
.auth-button { /* General button style */
    display: inline-block;
    background: linear-gradient(90deg, var(--secondary-color), #4169E1);
    color: white;
    border: none;
    padding: 12px 28px;
    border-radius: 25px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(106, 17, 203, 0.2);
}

.auth-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(106, 17, 203, 0.3);
}

.form-input {
    width: 100%;
    padding: 0.8rem 1rem;
    border: 1px solid #dcdcdc;
    border-radius: 8px;
    font-size: 1rem;
    background: #f9f9f9;
}

.form-input:focus {
    outline: none;
    border-color: var(--secondary-color);
    background: white;
    box-shadow: 0 0 0 3px rgba(106, 17, 203, 0.15);
}

.form-group {
    margin-bottom: 1rem;
}


/* --- Responsive Adjustments --- */
@media (max-width: 900px) {
    .checkout-grid {
        grid-template-columns: 1fr; /* Stack columns on smaller screens */
    }

    .order-summary-column {
        position: static;
        top: auto;
    }
    
    #checkout-page .section-title {
        font-size: 2rem;
    }
}