:root {
    --sidebar-width: 250px;
    --primary-color: #0d6efd;
    --bg-dark: #212529;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f7fa;
}

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: var(--bg-dark);
    z-index: 1000;
    overflow-y: auto;
}

.sidebar-brand {
    padding: 1rem;
    color: #fff;
    font-size: 1.25rem;
    font-weight: 700;
    border-bottom: 1px solid rgba(255,255,255,.1);
}

.sidebar .nav-link {
    color: rgba(255,255,255,.7);
    padding: .75rem 1rem;
    border-radius: 0;
    transition: all .2s;
}

.sidebar .nav-link:hover,
.sidebar .nav-link.active {
    color: #fff;
    background: rgba(255,255,255,.1);
}

.sidebar .nav-link i {
    margin-right: .75rem;
    width: 20px;
    text-align: center;
}

.main-content {
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

.page-header {
    padding: 1.5rem 0;
    border-bottom: 1px solid #dee2e6;
    margin-bottom: 1.5rem;
}

.email-list .email-item {
    cursor: pointer;
    transition: background .15s;
    border-left: 3px solid transparent;
}

.email-list .email-item:hover {
    background: #f0f4ff;
}

.email-list .email-item.unread {
    border-left-color: var(--primary-color);
    font-weight: 600;
}

.email-list .email-item .email-subject {
    font-weight: 500;
}

.email-preview .email-header {
    border-bottom: 1px solid #dee2e6;
    padding-bottom: 1rem;
    margin-bottom: 1rem;
}

.search-filters .card {
    margin-bottom: 1rem;
}

.stat-card {
    transition: transform .2s;
}

.stat-card:hover {
    transform: translateY(-3px);
}

.avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    color: #fff;
}

@media (max-width: 768px) {
    .sidebar {
        width: 100%;
        height: auto;
        position: relative;
    }
    .main-content {
        margin-left: 0;
    }
}

.pagination .page-link {
    cursor: pointer;
}

.toast-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 9999;
}