body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: #f8f9fa;
    color: #212529;
}
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1rem;
}
main {
    padding: 2rem 0;
}
.card {
    border-radius: 0.75rem;
}
.inbox-feed,
.chat-log {
    list-style: none;
    margin: 0;
    padding: 0;
}
.inbox-feed li,
.chat-log li {
    padding: 1rem;
    border-bottom: 1px solid #e9ecef;
    background: #fff;
    margin-bottom: 0.5rem;
}
.tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}
.tab-button {
    background: #fff;
    border: 1px solid #dee2e6;
    border-radius: 0.5rem;
    padding: 0.75rem 1rem;
    cursor: pointer;
    color: #212529;
}
.tab-button.active {
    background: #0d6efd;
    color: #fff;
    border-color: #0d6efd;
}
.tab-panel {
    display: none;
}
.tab-panel.active {
    display: block;
}
footer {
    background: #fff;
    padding: 1rem 0;
    border-top: 1px solid #dee2e6;
    text-align: center;
}