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

:root {
    --primary: #667eea;
    --primary-dark: #5a67d8;
    --secondary: #764ba2;
    --success: #48bb78;
    --danger: #f56565;
    --warning: #ed8936;
    --info: #4299e1;
    --dark: #2d3748;
    --light: #f7fafc;
    --border: #e2e8f0;
    --text: #2d3748;
    --text-light: #718096;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: var(--text);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

/* Header */
.header {
    background: white;
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.logo h1 {
    color: var(--primary);
    font-size: 2em;
    margin-bottom: 5px;
}

.logo p {
    color: var(--text-light);
    font-size: 0.9em;
}

.header-actions {
    display: flex;
    gap: 15px;
    align-items: center;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 15px;
    background: var(--light);
    border-radius: 8px;
}

.status-indicator .dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--danger);
    animation: pulse 2s infinite;
}

.status-indicator.connected .dot {
    background: var(--success);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.status-indicator .label {
    font-size: 0.9em;
    color: var(--text-light);
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 25px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 20px;
    transition: transform 0.3s, box-shadow 0.3s;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.stat-icon {
    font-size: 3em;
    opacity: 0.8;
}

.stat-content h3 {
    font-size: 2em;
    color: var(--primary);
    margin-bottom: 5px;
}

.stat-content p {
    color: var(--text-light);
    font-size: 0.9em;
}

/* Section */
.section {
    background: white;
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 30px;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 2px solid var(--border);
}

.section-header h2 {
    color: var(--dark);
    font-size: 1.5em;
}

/* Sessions Container */
.sessions-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 20px;
}

.session-card {
    background: var(--light);
    padding: 20px;
    border-radius: 12px;
    border: 2px solid var(--border);
    transition: all 0.3s;
}

.session-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow);
}

.session-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.session-id {
    font-weight: bold;
    color: var(--dark);
    font-size: 1.1em;
}

.session-status {
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.8em;
    font-weight: 600;
    text-transform: uppercase;
}

.session-status.connected {
    background: var(--success);
    color: white;
}

.session-status.connecting {
    background: var(--warning);
    color: white;
}

.session-status.disconnected {
    background: var(--danger);
    color: white;
}

.session-info {
    margin: 15px 0;
}

.session-info-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
    font-size: 0.9em;
}

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

.session-info-label {
    color: var(--text-light);
}

.session-info-value {
    color: var(--dark);
    font-weight: 500;
}

.session-actions {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

.session-actions .btn {
    flex: 1;
    padding: 8px;
    font-size: 0.85em;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-secondary {
    background: var(--light);
    color: var(--dark);
    border: 2px solid var(--border);
}

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

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

.btn-danger:hover {
    background: #e53e3e;
}

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

.btn-info:hover {
    background: #3182ce;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s;
}

.modal.show {
    display: flex;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal-content {
    background: white;
    border-radius: 20px;
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.3s;
}

.modal-large {
    max-width: 900px;
}

@keyframes slideUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-header {
    padding: 25px;
    border-bottom: 2px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    color: var(--dark);
}

.close-btn {
    background: none;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    color: var(--text-light);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.3s;
}

.close-btn:hover {
    background: var(--light);
    color: var(--dark);
}

.modal-body {
    padding: 25px;
}

.modal-footer {
    padding: 20px 25px;
    border-top: 2px solid var(--border);
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

/* Form */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--dark);
    font-weight: 600;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 1em;
    transition: border-color 0.3s;
}

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

.form-group small {
    display: block;
    margin-top: 5px;
    color: var(--text-light);
    font-size: 0.85em;
}

/* QR Code */
.qr-code {
    background: white;
    padding: 20px;
    border-radius: 12px;
    display: inline-block;
    margin: 20px auto;
    box-shadow: var(--shadow);
}

.pairing-code {
    font-size: 3em;
    font-weight: bold;
    color: var(--primary);
    background: var(--light);
    padding: 30px;
    border-radius: 15px;
    margin: 20px 0;
    letter-spacing: 5px;
}

.instructions {
    text-align: left;
    background: var(--light);
    padding: 20px;
    border-radius: 10px;
    margin-top: 20px;
    line-height: 1.8;
}

/* Loading */
.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-light);
}

.spinner {
    border: 4px solid var(--border);
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Utilities */
.text-center {
    text-align: center;
}

.mt-20 {
    margin-top: 20px;
}

.mb-20 {
    margin-bottom: 20px;
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        flex-direction: column;
        align-items: flex-start;
    }

    .stats-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }

    .sessions-container {
        grid-template-columns: 1fr;
    }

    .modal-content {
        width: 95%;
    }
}