body {
    background: #eef2f7;
    min-height: 100vh;
}

.app-shell {
    display: flex;
    min-height: 100vh;
}

.app-sidebar {
    width: 260px;
    background: #fff;
    border-right: 1px solid #e9ecef;
    padding: 12px;
}

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 4px 10px 4px;
    border-bottom: 1px solid #f1f3f5;
    margin-bottom: 10px;
}

.sidebar-title {
    font-weight: 700;
    font-size: 0.85rem;
    color: #6c757d;
    letter-spacing: 0.02em;
}

.sidebar-toggle {
    border: 1px solid #e9ecef;
    background: #fff;
    border-radius: 6px;
    width: 36px;
    height: 32px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.sidebar-link {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 10px;
    border-radius: 10px;
    color: #343a40;
    text-decoration: none;
    font-weight: 600;
}

.sidebar-link:hover {
    background: #f1f5ff;
    color: #0000FF;
}

.sidebar-link.active {
    background: #e8f0ff;
    color: #0000FF;
}

.app-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.app-topbar {
    background: #fff;
    border-bottom: 1px solid #e9ecef;
}

.app-content {
    padding: 24px;
}

body.sidebar-collapsed .app-sidebar {
    width: 72px;
    padding: 12px 8px;
}

body.sidebar-collapsed .sidebar-title,
body.sidebar-collapsed .sidebar-text {
    display: none;
}

/* Sidebar UX improvements: clearer active, smaller footprint */
.app-sidebar { width: 250px; padding: 10px; }
.sidebar-header { margin-bottom: 8px; }
.sidebar-title { font-size: 0.75rem; text-transform: uppercase; }
.sidebar-link { font-size: 0.95rem; padding: 9px 10px; border-radius: 10px; line-height: 1.2; position: relative; }
.sidebar-link i { width: 18px; text-align: center; opacity: 0.9; }
.sidebar-text { min-width: 0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.sidebar-link:hover { background: #f1f5ff; }
.sidebar-link.active { background: #e8f0ff; }
.sidebar-link.active::before { content: ""; position: absolute; left: 0; top: 8px; bottom: 8px; width: 3px; background: #0000FF; border-radius: 4px; }
.sidebar-link:focus-visible { outline: 2px solid rgba(0, 0, 255, 0.35); outline-offset: 2px; }
body.sidebar-collapsed .app-sidebar { width: 64px; padding: 10px 8px; }
body.sidebar-collapsed .sidebar-link { justify-content: center; padding: 10px 8px; }
body.sidebar-collapsed .sidebar-link i { width: auto; }
body.sidebar-collapsed .sidebar-link.active::before { top: 10px; bottom: 10px; }

.profile-box { background: #fff; padding: 32px; margin: 24px auto; max-width: 420px; border-radius: 12px; box-shadow: 0 2px 12px #ccc; }
.profile-avatar { width: 80px; height: 80px; border-radius: 50%; margin-bottom: 16px; cursor: pointer; }
.profile-name { font-size: 1.4rem; font-weight: bold; color: #3a3a3a; }
.profile-mssv { color: #888; }

.sr-only-input {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}