* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Segoe UI", Arial, sans-serif;
}

body {
    background: #f3f4f6;
    color: #333;
    padding-bottom: 30px;
    line-height: 1.5;
}

/* Header and Navigation */
header {
    background: #2c3e50;
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    padding: 15px max(20px, calc((100% - 1100px) / 2));
}

.logo {
    font-size: 22px;
    font-weight: 700;
    white-space: nowrap;
}

nav {
    display: flex;
    flex-wrap: wrap;
    gap: 18px;
}

nav a {
    color: #ddd;
    text-decoration: none;
    font-weight: 500;
}

nav a:hover,
nav a.active {
    color: #70c5ff;
}

/* Currency and Tax Settings */
.settings-panel,
.invoice-container,
.management-actions {
    max-width: 900px;
    margin: 24px auto 0;
}

.settings-panel {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 14px;
    background: white;
    border: 1px solid #e1e5e9;
    border-radius: 8px;
    padding: 18px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
}

.setting-field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.setting-field label {
    font-size: 14px;
    font-weight: 700;
}

.setting-field select,
.setting-field input {
    width: 100%;
    min-height: 42px;
    padding: 9px 10px;
    border: 1px solid #cbd2d9;
    border-radius: 5px;
    background: #fff;
    color: #222;
    font-size: 15px;
}

.settings-note {
    grid-column: 1 / -1;
    font-size: 12px;
    color: #666;
}

/* Invoice Sheet */
.invoice-container {
    background: white;
    padding: 38px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    overflow-wrap: anywhere;
}

.invoice-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 24px;
    margin-bottom: 22px;
}

.shop-details {
    min-width: 0;
}

.shop-details h1 {
    font-size: 25px;
    margin-bottom: 8px;
    color: #243447;
}

.shop-details p,
.bill-details p {
    margin: 5px 0;
}

.bill-details {
    text-align: right;
    min-width: 150px;
}

.bill-details h2 {
    font-size: 25px;
    letter-spacing: 1px;
    margin-bottom: 8px;
    color: #2c3e50;
}

/* Editable Text */
[contenteditable="true"] {
    border-bottom: 1px dashed #c9cdd1;
    padding: 2px 4px;
    outline: none;
    overflow-wrap: anywhere;
}

[contenteditable="true"]:focus {
    background: #f5faff;
    border-bottom: 1px solid #3498db;
}

/* Customer Details */
.customer-section {
    margin: 20px 0;
    line-height: 1.8;
}

.customer-section h3 {
    margin-bottom: 5px;
}

.invoice-container hr {
    border: 0;
    border-top: 1px solid #ddd;
    margin: 18px 0;
}

/* Invoice Items Table */
.table-wrap {
    width: 100%;
    overflow-x: auto;
}

.invoice-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 18px;
}

.invoice-table th,
.invoice-table td {
    border: 1px solid #d8dde2;
    padding: 10px;
    text-align: left;
    vertical-align: top;
}

.invoice-table th {
    background: #f1f4f7;
    font-weight: 700;
}

.invoice-table td[contenteditable="true"] {
    min-width: 55px;
}

.invoice-table td.item-name {
    min-width: 160px;
}

.item-total-cell {
    white-space: nowrap;
}

/* Buttons */
.btn {
    border: 0;
    border-radius: 5px;
    padding: 10px 16px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 700;
    transition: filter 0.15s ease;
}

.btn:hover {
    filter: brightness(0.94);
}

.invoice-actions {
    margin-top: 14px;
}

.btn-add {
    background: #219653;
    color: white;
}

.btn-delete {
    background: #c0392b;
    color: white;
    padding: 5px 10px;
}

.btn-print {
    background: #287fbd;
    color: white;
    width: 100%;
    font-size: 16px;
    padding: 13px 16px;
}

/* Subtotal, Tax and Grand Total */
.calculation-box {
    width: min(100%, 370px);
    margin: 26px 0 0 auto;
    border: 1px solid #e1e5e9;
    padding: 16px;
    background: #fafbfc;
    border-radius: 6px;
}

.calc-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    margin-bottom: 10px;
    font-size: 15px;
}

.calc-row > span:last-child {
    white-space: nowrap;
}

.grand-total-row {
    margin: 12px 0 0;
    color: #23384d;
}

.grand-total-row h3 {
    font-size: 17px;
}

.save-status {
    margin-top: 16px;
    color: #287647;
    font-size: 12px;
}

.print-actions {
    margin-top: 24px;
}

/* New Invoice and Clear Invoice */
.management-actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
    padding: 0 2px;
}

.btn-secondary {
    background: #5d6d7e;
    color: white;
}

.btn-danger {
    background: #b83227;
    color: white;
}

.storage-note {
    flex-basis: 100%;
    color: #666;
    font-size: 12px;
}

/* Footer */
.site-footer {
    margin-top: 36px;
    padding: 22px 16px;
    background: #f8f9fa;
    text-align: center;
    border-top: 1px solid #ddd;
    color: #444;
}

.site-footer a {
    color: #0d6efd;
    text-decoration: none;
    font-weight: 600;
}

.site-footer a:hover {
    text-decoration: underline;
}

.footer-links {
    margin-top: 10px;
}

.powered-by {
    margin-top: 10px;
}

/* Mobile Responsive */
@media (max-width: 700px) {
    header {
        padding: 14px 16px;
        flex-direction: column;
        align-items: flex-start;
    }

    nav {
        gap: 14px;
    }

    .settings-panel,
    .invoice-container,
    .management-actions {
        margin-left: 12px;
        margin-right: 12px;
    }

    .settings-panel {
        grid-template-columns: 1fr;
        padding: 14px;
    }

    .settings-note {
        grid-column: auto;
    }

    .invoice-container {
        padding: 20px 14px;
    }

    .invoice-header {
        flex-direction: column;
        gap: 18px;
    }

    .bill-details {
        text-align: left;
    }

    .shop-details h1 {
        font-size: 21px;
    }

    .invoice-table th,
    .invoice-table td {
        padding: 8px;
        font-size: 13px;
    }

    .invoice-table td.item-name {
        min-width: 140px;
    }
}