:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --success-color: #2ecc71;
    --error-color: #e74c3c;
    --bg-color: #f4f7f9;
    --card-bg-color: #ffffff;
    --text-color: #333;
    --text-light-color: #777;
    --border-color: #e0e0e0;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    --border-radius: 8px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background-color: var(--secondary-color);
    color: white;
    padding: 15px 20px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    font-size: 1.5rem;
    margin: 0;
}

.api-status {
    display: flex;
    align-items: center;
    font-size: 0.9rem;
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: #e74c3c; /* Default to offline */
    margin-right: 8px;
    transition: background-color 0.5s;
}

.status-dot.online {
    background-color: var(--success-color);
}

.search-box {
    background-color: var(--card-bg-color);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 30px;
}

.search-box h2 {
    margin-bottom: 15px;
    font-size: 1.2rem;
    color: var(--secondary-color);
}

.input-group {
    display: flex;
    gap: 10px;
}

#card-number-input {
    flex-grow: 1;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
}

#card-number-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

#search-btn {
    padding: 12px 25px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

#search-btn:hover {
    background-color: #2980b9;
}

.loading-indicator, .error-message {
    text-align: center;
    padding: 40px;
    font-size: 1.1rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.error-message {
    color: var(--error-color);
    background-color: rgba(231, 76, 60, 0.1);
    border: 1px solid rgba(231, 76, 60, 0.2);
    border-radius: var(--border-radius);
}

.results-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
}

.card-info-section, .transactions-section {
    background-color: var(--card-bg-color);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

h3 {
    font-size: 1.2rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
}

.card-visual {
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
    color: white;
    border-radius: 15px;
    padding: 15px;
    margin-bottom: 20px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    font-weight: bold;
}

.status-badge {
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}
.status-badge.active { background-color: rgba(46, 204, 113, 0.8); }
.status-badge.frozen { background-color: rgba(241, 196, 15, 0.8); }
.status-badge.closed { background-color: rgba(231, 76, 60, 0.8); }

.card-number {
    font-family: 'Courier New', monospace;
    font-size: 1.5rem;
    letter-spacing: 3px;
    text-align: center;
    margin-bottom: 25px;
    white-space: nowrap;
}

.card-footer {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
}

.card-footer .label {
    display: block;
    font-size: 0.7rem;
    opacity: 0.7;
    margin-bottom: 3px;
}

.value-with-copy {
    display: flex;
    align-items: center;
    gap: 8px;
}

.copy-icon {
    cursor: pointer;
    width: 16px;
    height: 16px;
    background-image: url('data:image/svg+xml;charset=UTF-8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="currentColor" opacity="0.6"><path d="M16 1H4c-1.1 0-2 .9-2 2v14h2V3h12V1zm3 4H8c-1.1 0-2 .9-2 2v14c0 1.1.9 2 2 2h11c1.1 0 2-.9 2-2V7c0-1.1-.9-2-2-2zm0 16H8V7h11v14z"/></svg>');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
    transition: opacity 0.2s;
}

.copy-icon:hover {
    opacity: 1;
}

.info-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 15px;
}

.info-item.balance-item {
    grid-column: 1 / -1;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
}

.info-sub-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
    grid-column: 1 / -1;
}

.info-item {
    background-color: var(--bg-color);
    padding: 15px;
    border-radius: var(--border-radius);
}

.info-item .label {
    display: block;
    font-size: 0.9rem;
    color: var(--text-light-color);
    margin-bottom: 5px;
}

.info-item.balance-item .label {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--secondary-color);
}

.info-item .value {
    font-size: 1.1rem;
    font-weight: 500;
}

.info-item.balance-item .value {
    font-size: 2rem;
    font-weight: bold;
}

.info-item .amount {
    color: var(--success-color);
}
.info-item.address {
    grid-column: 1 / -1;
}

.transactions-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.transaction-item {
    padding: 15px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    transition: box-shadow 0.3s;
}
.transaction-item:hover {
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.transaction-main {
    display: grid;
    grid-template-columns: 1fr auto;
    grid-template-rows: auto auto;
    gap: 5px 15px;
}

.transaction-details {
    grid-column: 1;
    grid-row: 1;
}
.transaction-details .merchant {
    font-weight: 600;
}
.transaction-details .time {
    font-size: 0.8rem;
    color: var(--text-light-color);
}

.transaction-amount {
    grid-column: 2;
    grid-row: 1 / 3;
    text-align: right;
    align-self: center;
    font-size: 1.2rem;
    font-weight: 600;
}
.transaction-amount.credit { color: var(--success-color); }
.transaction-amount.debit { color: var(--error-color); }

.transaction-info {
    grid-column: 1;
    grid-row: 2;
    margin-top: 5px;
    font-size: 0.9rem;
    color: var(--text-light-color);
    display: flex;
    justify-content: space-between;
}

.transaction-info span {
    flex: 1;
    text-align: left;
    padding-right: 10px;
}
.transaction-info span:last-child {
    padding-right: 0;
}

.transaction-remark {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px dashed var(--border-color);
    font-size: 0.85rem;
    color: #555;
    line-height: 1.4;
    white-space: pre-wrap;
    word-break: break-word;
}


.fee-positive {
    color: var(--error-color);
    font-weight: 500;
}

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 20px;
    gap: 15px;
}

.pagination button {
    padding: 8px 16px;
    background-color: var(--card-bg-color);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: background-color 0.3s, color 0.3s;
}
.pagination button:hover:not(:disabled) {
    background-color: var(--primary-color);
    color: white;
}
.pagination button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Tablet and Desktop Styles */
@media (min-width: 768px) {
    .results-container {
        grid-template-columns: 400px 1fr;
        align-items: flex-start;
    }

    .transaction-main {
        grid-template-columns: 1fr 1fr 1fr auto;
        grid-template-rows: 1fr;
        align-items: center;
        gap: 0 15px;
    }
    .transaction-details {
        grid-column: auto;
        grid-row: auto;
    }
    .transaction-amount {
        grid-column: auto;
        grid-row: auto;
        text-align: left;
        align-self: center;
    }
    .transaction-info {
        grid-column: auto;
        grid-row: auto;
        margin-top: 0;
        padding-top: 0;
        border-top: none;
        justify-content: start;
    }
    .transaction-remark {
        padding-left: 10px;
    }
}

/* Mobile specific adjustments */
@media (max-width: 480px) {
    header {
        flex-direction: column;
        gap: 10px;
    }
    .input-group {
        flex-direction: column;
    }
    .card-number {
        font-size: 1.2rem;
        letter-spacing: 2px;
    }
}