/* === CSS Variables === */
:root {
    --md-border-color: #e5e7eb;
    --md-border-hover: #d1d5db;
    --md-border-radius: 0.75rem;
    --md-border-radius-sm: 0.5rem;
    --md-spacing: 1.5rem;
    --md-spacing-sm: 1rem;
    --md-text-primary: #111827;
    --md-text-secondary: #374151;
    --md-text-muted: #6b7280;
    --md-text-light: #9ca3af;
    --md-bg-primary: white;
    --md-bg-secondary: #f9fafb;
    --md-green: #059669;
    --md-green-dark: #047857;
    --md-cyan: #06b6d4;
    --md-font-size-base: 0.9375rem;
    --md-font-size-sm: 0.875rem;
    --md-font-size-lg: 1.2rem;
    --md-font-size-xl: 1.5rem;
    --md-font-size-2xl: 2.0rem;
    --md-font-size-3xl: 2.5rem;
}

/* === Container === */
.md-donation-wrapper {
    min-height: 100vh;
}

.md-donation-container {
    margin: 0 auto;
    background: var(--md-bg-primary);
    border-radius: var(--md-border-radius-sm);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    border: 1px solid var(--md-border-color);
}

/* === Header === */
.md-header {
    border-bottom: 1px solid var(--md-border-color);
    padding: var(--md-spacing) var(--md-spacing) 1.25rem;
}

.md-header h1 {
    font-size: var(--md-font-size-3xl);
    font-weight: 600;
    color: var(--md-text-primary);
    margin: 0 0 0.25rem 0;
}

.md-header p {
    font-size: var(--md-font-size-sm);
    color: var(--md-text-muted);
    margin: 0;
}

/* === Items Grid === */
.md-items-grid {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.md-item-card {
    border: 1px solid var(--md-border-color);
    border-radius: var(--md-border-radius-sm);
    padding: var(--md-spacing-sm);
    transition: border-color 0.2s;
}

.md-item-card:hover {
    border-color: var(--md-border-hover);
}

.md-item-header {
    margin-bottom: 0.75rem;
}

.md-item-info {
    width: 100%;
}

.md-item-info h3 {
    font-size: var(--md-font-size-xl);
    font-weight: 500;
    color: var(--md-text-primary);
    margin: 0 0 0.125rem 0;
}

.md-item-info p {
    font-size: var(--md-font-size-lg);
    color: var(--md-text-muted);
    margin: 0;
}

.md-item-price {
    font-size: var(--md-font-size-2xl);
    font-weight: 700;
    color: var(--md-green);
    white-space: nowrap;
    margin-left: auto;
}

/* === Controls === */
.md-item-controls {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.md-qty-btn {
    width: 40px;
    height: 40px;
    border: 2px solid #1A1A1A;
    border-radius: 30%;
    background-color: transparent;
    color: #3B3B3B;
    font-size: 20px;
    font-weight: 600;
    cursor: pointer;
    transition: all 300ms cubic-bezier(.23, 1, 0.32, 1);
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    padding: 0 !important;
    margin: 0 !important;
}

.md-qty-btn:hover:not(:disabled) {
    color: white;
    background-color: #1A1A1A;
    box-shadow: rgba(0, 0, 0, 0.25) 0 8px 15px;
    transform: translateY(-2px);
}

.md-qty-btn:active:not(:disabled) {
    box-shadow: none;
    transform: translateY(0);
}

.md-qty-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    border-color: #ccc;
}

.md-qty-display {
    min-width: 40px;
    text-align: center;
    font-weight: 600;
    font-size: 22px;
}

/* === Summary === */
.md-summary-section {
    border-top: 1px solid var(--md-border-color);
    padding: var(--md-spacing);
    background: var(--md-bg-secondary);
}

.md-receipt {
    background: var(--md-bg-primary);
    border-radius: var(--md-border-radius-sm);
    border: 1px solid var(--md-border-color);
    padding: 1.25rem;
    margin-bottom: 1.25rem;
}

.md-receipt-item {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    font-size: var(--md-font-size-lg);
}

.md-receipt-item .label {
    color: var(--md-text-secondary);
}

.md-receipt-item .amount {
    font-weight: 500;
    color: var(--md-text-primary);
}

.md-receipt-item.total {
    border-top: 2px solid var(--md-border-color);
    padding-top: var(--md-spacing-sm);
    margin-top: 0.5rem;
}

.md-receipt-item.total .label {
    font-weight: 600;
    color: var(--md-text-primary);
}

.md-receipt-item.total .amount {
    font-size: 1.375rem;
    font-weight: 700;
    color: var(--md-green);
}

.md-empty {
    text-align: center;
    color: var(--md-text-light);
    font-size: var(--md-font-size-sm);
    padding: 2rem 1.25rem;
    margin-bottom: 1.25rem;
}

/* === Form === */
.md-form {
    display: flex;
    flex-direction: column;
    gap: var(--md-spacing-sm);
}

.md-form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-weight: 500;
    color: var(--md-text-secondary);
    font-size: var(--md-font-size-base);
}

.md-form-group input,
.md-form-group textarea,
.md-open-amount {
    width: 100%;
    padding: 0.625rem 0.75rem !important;
    margin: 0 !important;
    border: 2px solid var(--md-border-color);
    border-radius: var(--md-border-radius) !important;
    font-size: var(--md-font-size-base);
    transition: all 0.2s;
}

.md-form-group input:focus,
.md-form-group textarea:focus {
    outline: none;
    border-color: var(--md-cyan);
    box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.1);
}

.md-form-group input.invalid,
.md-form-group textarea.invalid {
    border-color: #ef4444;
}

.md-form-group input.invalid:focus,
.md-form-group textarea.invalid:focus {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.md-open-amount {
    text-align: center;
    font-size: var(--md-font-size-2xl);
    font-weight: 600;
}

.md-open-amount:focus {
    outline: none;
    border-color: var(--md-green);
}

.md-open-amount::-webkit-inner-spin-button,
.md-open-amount::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.md-form-group textarea {
    font-family: inherit;
    resize: vertical;
}

.md-submit-btn {
    width: 100%;
    padding: 0.75rem;
    background: var(--md-green);
    color: white;
    border: none;
    border-radius: var(--md-border-radius);
    font-size: var(--md-font-size-2xl);
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
    margin-top: 0.25rem;
}

.md-submit-btn:hover:not(:disabled) {
    background: var(--md-green-dark);
}

.md-submit-btn:disabled,
.md-submit-btn.loading {
    opacity: 0.5;
    cursor: not-allowed;
}

/* === Responsive === */
@media (max-width: 640px) {
    .md-form-group input {
        font-size: 16px;
    }
}

@media (min-width: 768px) {
    .md-item-card {
        display: flex;
        align-items: center;
        gap: var(--md-spacing);
    }
    
    .md-item-header {
        flex: 1;
        margin-bottom: 0;
    }
    
    .md-item-controls {
        flex-shrink: 0;
        width: 320px;
    }
    
    .md-open-amount {
        width: 320px;
        padding: 0 !important;
        margin: 0 !important;
        border-radius: 8px !important;
    }
}