:root {
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --primary-light: #eef2ff;
    --success-color: #059669;
    --success-light: #ecfdf5;
    --danger-color: #ef4444;
    --danger-light: #fef2f2;
    --bg-page: #f8fafc;
    --bg-card: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --border-focus: #818cf8;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
}

* {
    box-sizing: border-box;
}

body {
    background-color: var(--bg-page);
    color: var(--text-main);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0;
    padding: 0;
    -webkit-font-smoothing: antialiased;
}

/* App Container - Mobile First Max 620px */
.calculator-app {
    max-width: 620px;
    margin: 0 auto;
    padding: 1.25rem 0.85rem 3rem 0.85rem;
}

/* Header */
.app-header {
    text-align: center;
    margin-bottom: 1.5rem;
    padding: 0.5rem 0;
}

.app-title {
    font-size: 1.65rem;
    font-weight: 800;
    color: var(--text-main);
    letter-spacing: -0.5px;
    margin-bottom: 0.25rem;
}

.app-subtitle {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin: 0;
}

/* Items Container */
.items-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* Item Card */
.item-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.item-card:hover {
    box-shadow: var(--shadow-md);
    border-color: #cbd5e1;
}

.item-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1rem;
    background-color: #f8fafc;
    border-bottom: 1px solid var(--border-color);
}

.item-badge-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.item-index-badge {
    background-color: var(--primary-color);
    color: #ffffff;
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.2rem 0.55rem;
    border-radius: 6px;
    letter-spacing: 0.3px;
}

.item-type-label {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--text-main);
    text-transform: uppercase;
}

.btn-remove-item {
    background: none;
    border: none;
    color: var(--danger-color);
    font-size: 0.8125rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.15s ease;
}

.btn-remove-item:hover {
    background-color: var(--danger-light);
}

/* Card Body */
.item-card-body {
    padding: 1rem;
}

/* Form Group */
.form-field-group {
    margin-bottom: 0.85rem;
}

.field-label {
    display: block;
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.35rem;
}

.field-input, .field-select {
    width: 100%;
    padding: 0.6rem 0.75rem;
    font-size: 0.925rem;
    font-weight: 500;
    color: var(--text-main);
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    outline: none;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.field-input:focus, .field-select:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.field-input::placeholder {
    color: #94a3b8;
}

/* 2-Column Grid for Measurement Inputs */
.fields-grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

/* Line Result Bar */
.item-result-bar {
    margin-top: 0.75rem;
    padding: 0.75rem 0.85rem;
    background-color: #f1f5f9;
    border-radius: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem;
    border: 1px solid #e2e8f0;
}

.result-qty-block {
    display: flex;
    flex-direction: column;
}

.result-qty-label {
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
}

.result-qty-value {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--primary-color);
}

.result-amount-block {
    text-align: right;
}

.result-amount-label {
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
}

.result-amount-value {
    font-size: 1.05rem;
    font-weight: 800;
    color: var(--text-main);
}

.result-discount-detail {
    font-size: 0.725rem;
    color: var(--danger-color);
    font-weight: 600;
}

/* Add Item Button */
.add-item-section {
    margin: 1.25rem 0 1.5rem 0;
}

.btn-add-item {
    width: 100%;
    padding: 0.85rem 1rem;
    background-color: #ffffff;
    color: var(--primary-color);
    border: 2px dashed #c7d2fe;
    border-radius: 12px;
    font-size: 0.95rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-add-item:hover {
    background-color: var(--primary-light);
    border-color: var(--primary-color);
}

/* Summary Card */
.summary-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.25rem;
    box-shadow: var(--shadow-md);
    margin-top: 1rem;
}

.summary-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
}

.summary-header h2 {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--text-main);
    margin: 0;
}

.item-count-badge {
    background-color: #f1f5f9;
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
}

.summary-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.4rem 0;
    font-size: 0.925rem;
}

.summary-label {
    font-weight: 600;
    color: var(--text-muted);
}

.summary-value {
    font-weight: 700;
    color: var(--text-main);
}

.discount-row .summary-label {
    color: #ef4444;
}

.summary-divider {
    margin: 0.75rem 0;
    border: none;
    border-top: 1px solid var(--border-color);
}

/* Net Payable Box */
.net-payable-box {
    background: linear-gradient(135deg, #065f46 0%, #047857 100%);
    color: #ffffff;
    border-radius: 12px;
    padding: 1rem 1.25rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 0.5rem;
    box-shadow: 0 4px 10px rgba(5, 150, 105, 0.25);
}

.net-payable-text {
    display: flex;
    flex-direction: column;
}

.net-payable-title {
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.75px;
    text-transform: uppercase;
    color: #a7f3d0;
}

.net-payable-sub {
    font-size: 0.75rem;
    color: #e2e8f0;
    opacity: 0.9;
}

.net-payable-amount {
    font-size: 1.65rem;
    font-weight: 900;
    letter-spacing: -0.5px;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 2.5rem 1rem;
    background-color: #ffffff;
    border: 1px dashed var(--border-color);
    border-radius: 14px;
    color: var(--text-muted);
}

.empty-state-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    opacity: 0.7;
}

.empty-state p {
    margin: 0;
    font-size: 0.9rem;
}

/* Responsive Tweaks */
@media (max-width: 480px) {
    .calculator-app {
        padding: 0.75rem 0.5rem 2rem 0.5rem;
    }

    .app-title {
        font-size: 1.45rem;
    }

    .item-card-body {
        padding: 0.85rem;
    }

    .net-payable-amount {
        font-size: 1.4rem;
    }
}

/* Customer Card */
.customer-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 1rem;
    overflow: hidden;
}

.customer-card-header {
    padding: 0.65rem 1rem;
    background-color: #f8fafc;
    border-bottom: 1px solid var(--border-color);
}

.customer-card-title {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.customer-card-body {
    padding: 0.85rem 1rem;
}

/* Action Buttons Section */
.quotation-actions-section {
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
    margin-top: 1.25rem;
}

.btn-action {
    width: 100%;
    padding: 0.75rem 1rem;
    border-radius: 10px;
    font-size: 0.95rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-whatsapp {
    background-color: #25d366;
    color: #ffffff;
    box-shadow: 0 2px 8px rgba(37, 211, 102, 0.3);
}

.btn-whatsapp:hover {
    background-color: #20ba59;
    box-shadow: 0 4px 12px rgba(37, 211, 102, 0.4);
}

.btn-download-pdf {
    background-color: #ffffff;
    color: var(--text-main);
    border: 1px solid var(--border-color);
}

.btn-download-pdf:hover {
    background-color: #f1f5f9;
    border-color: #cbd5e1;
}