:root {
    --primary-color: #0f4c81;
    --primary-hover: #0c3b65;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --bg-light: #f8fafc;
    --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
}

body {
    background-color: var(--bg-light);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: #334155;
}

.navbar-brand-star {
    font-weight: 700;
    letter-spacing: -0.5px;
}

.card {
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
}

.card-header {
    background-color: #ffffff;
    border-bottom: 1px solid #f1f5f9;
    font-weight: 600;
}

.nav-pills .nav-link {
    color: #64748b;
    font-weight: 500;
    border-radius: 8px;
    padding: 10px 18px;
    transition: all 0.2s ease;
}

.nav-pills .nav-link.active {
    background-color: var(--primary-color);
    color: #ffffff;
    box-shadow: 0 4px 12px rgba(15, 76, 129, 0.25);
}

.nav-pills .nav-link:hover:not(.active) {
    background-color: #e2e8f0;
    color: #1e293b;
}

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

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

.badge-due {
    background-color: #fef3c7;
    color: #b45309;
    border: 1px solid #fde68a;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.7; }
    100% { opacity: 1; }
}

.log-console {
    background-color: #1e293b;
    color: #f8fafc;
    font-family: "Courier New", Courier, monospace;
    font-size: 0.85rem;
    max-height: 250px;
    overflow-y: auto;
    border-radius: 8px;
    padding: 12px;
}

.log-entry {
    line-height: 1.5;
    word-break: break-all;
}

.log-entry.success {
    color: #34d399;
}

.log-entry.failed {
    color: #f87171;
}

.log-entry.info {
    color: #60a5fa;
}

.recipient-counter-badge {
    font-size: 0.9rem;
    font-weight: 600;
}

.stats-card {
    border-radius: 10px;
    padding: 16px;
    text-align: center;
}

.stats-card .stats-num {
    font-size: 1.8rem;
    font-weight: 700;
}

.stats-card .stats-label {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}