:root {
    --primary-color: #4CAF50;
    --danger-color: #f44336;
    --warning-color: #ff9800;
    --bg-color: #f5f5f5;
    --card-bg: white;
    --text-color: #333;
    --border-color: #ddd;
    --success-bg: #d4edda;
    --danger-bg: #f8d7da;
    --warning-bg: #fff3cd;
}

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

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

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

/* Navigation */
.navbar {
    background: var(--card-bg);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 1rem 0;
    margin-bottom: 2rem;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background 0.3s;
}

.nav-links a:hover,
.nav-links a.active {
    background: var(--bg-color);
}

/* Main Content */
h1 {
    margin-bottom: 2rem;
    color: var(--text-color);
}

/* Monitors Grid */
.monitors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.monitor-card {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    border-left: 4px solid var(--border-color);
}

.monitor-card.status-up {
    border-left-color: var(--primary-color);
}

.monitor-card.status-down {
    border-left-color: var(--danger-color);
}

.monitor-card.status-unknown {
    border-left-color: var(--warning-color);
}

.monitor-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.monitor-header h3 {
    margin: 0;
}

.status-badge {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: bold;
}

.status-badge.up {
    background: var(--success-bg);
    color: var(--primary-color);
}

.status-badge.down {
    background: var(--danger-bg);
    color: var(--danger-color);
}

.status-badge.unknown {
    background: var(--warning-bg);
    color: var(--warning-color);
}

.monitor-details p {
    margin: 0.5rem 0;
    font-size: 0.9rem;
}

.monitor-details .url {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.monitor-actions {
    margin-top: 1rem;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem;
    background: var(--card-bg);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.empty-state p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    color: #666;
}

/* Forms */
.form {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 2rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    max-width: 600px;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-group input[type="text"],
.form-group input[type="url"],
.form-group input[type="email"],
.form-group input[type="number"] {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group small {
    display: block;
    margin-top: 0.25rem;
    color: #666;
    font-size: 0.875rem;
}

.form-group input[type="checkbox"] {
    margin-right: 0.5rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: background 0.3s;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: #45a049;
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background: #da190b;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* History Table */
.history-table {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    margin: 2rem 0;
    overflow-x: auto;
}

.history-table table {
    width: 100%;
    border-collapse: collapse;
}

.history-table th,
.history-table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.history-table th {
    background: var(--bg-color);
    font-weight: 600;
}

.history-table tr.status-up {
    background: rgba(76, 175, 80, 0.05);
}

.history-table tr.status-down {
    background: rgba(244, 67, 54, 0.05);
}

/* Monitor Info */
.monitor-info {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
}

.monitor-info p {
    margin: 0.5rem 0;
}

/* Settings */
.settings-section {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 2rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
}

.settings-section h2 {
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.config-display {
    background: var(--bg-color);
    border-radius: 4px;
    padding: 1rem;
    margin: 1.5rem 0;
}

.config-item {
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.config-item:last-child {
    border-bottom: none;
}

.config-item code {
    background: white;
    padding: 0.25rem 0.5rem;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
}

.help-section {
    margin-top: 2rem;
}

.help-section h3 {
    margin: 1.5rem 0 0.75rem;
    color: var(--text-color);
}

.help-section ul {
    margin-left: 2rem;
}

.help-section pre {
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 4px;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
}

.info {
    background: #e3f2fd;
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1.5rem;
    border-left: 4px solid #2196f3;
}

/* Responsive */
@media (max-width: 768px) {
    .monitors-grid {
        grid-template-columns: 1fr;
    }

    .nav-links {
        gap: 1rem;
    }

    .nav-links a {
        padding: 0.25rem 0.5rem;
    }

    .form-actions {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}

/* Statistics Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.stat-card {
    background: var(--card-bg);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-align: center;
}

.stat-card h3 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-card p {
    color: #666;
    font-size: 0.9rem;
}

/* Chart Container */
.chart-container {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin: 2rem 0;
}

.chart-container h2 {
    margin-bottom: 1.5rem;
    color: var(--text-color);
}