.lnb-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 15px;
    margin-top: 20px;
}
.lnb-item {
    border: 1px solid #ddd;
    padding: 10px;
    text-align: center;
    cursor: pointer;
    position: relative;
    background: #fff;
    transition: 0.3s;
}
.lnb-item.selected {
    border-color: #ffcc00;
    box-shadow: 0 0 10px rgba(255, 204, 0, 0.5);
}
.lnb-item img {
    max-width: 100%;
    height: auto;
}
.lnb-item-name {
    font-size: 12px;
    height: 36px;
    overflow: hidden;
    margin-top: 5px;
}
.lnb-item-price {
    font-weight: bold;
    color: #2ecc71;
}
.lnb-item-checkbox {
    position: absolute;
    top: 5px;
    left: 5px;
}

/* Header & Menu Buttons */
.lnb-sell-btn-nav, .lnb-sell-btn-header {
    background: #ffcc00 !important;
    color: #000 !important;
    font-weight: bold !important;
    border-radius: 4px !important;
    padding: 5px 15px !important;
    text-transform: uppercase;
    font-size: 13px;
    display: inline-block;
    transition: background 0.3s;
}
.lnb-sell-btn-nav:hover, .lnb-sell-btn-header:hover {
    background: #e6b800 !important;
}
.nasa-header-sell-wrap {
    display: inline-block;
    vertical-align: middle;
    margin: 0 10px;
}

/* Error messages */
.lnb-error {
    background: #fff3cd;
    border: 1px solid #ffc107;
    border-radius: 4px;
    padding: 20px;
    margin: 20px 0;
}

.lnb-inventory-error {
    background: #f8d7da;
    border: 1px solid #dc3545;
    border-radius: 4px;
    padding: 20px;
    margin: 20px 0;
}

.lnb-inventory-error h3 {
    color: #721c24;
    margin-top: 0;
}

.lnb-inventory-error h4 {
    color: #721c24;
    margin-top: 15px;
}

.lnb-inventory-error ol {
    margin: 10px 0;
    padding-left: 25px;
}

.lnb-inventory-error li {
    margin: 8px 0;
}

.lnb-inventory-error a {
    color: #0056b3;
    text-decoration: underline;
}

.lnb-login-box {
    text-align: center;
    padding: 30px;
    background: #f8f9fa;
    border-radius: 8px;
    margin: 20px 0;
}

.lnb-login-box p {
    margin-bottom: 15px;
    font-size: 16px;
}

.lnb-trade-url-wrapper {
    position: relative;
}

.lnb-trade-url-wrapper small {
    display: block;
    margin-top: 5px;
}

.lnb-trade-url-wrapper small a {
    color: #0073aa;
    text-decoration: none;
}

.lnb-trade-url-wrapper small a:hover {
    text-decoration: underline;
}