body { font-family: system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; background-color: #f5f7fb; }
.btn-lg, .form-control-lg { border-radius: 12px; padding: 14px 20px; }
.card { border-radius: 20px; overflow: hidden; }
.navbar-brand { font-size: 1.5rem; }
.option-btn:hover { background-color: #f8f9fa; transform: translateX(4px); }
@media (max-width: 576px) { .container { padding-left: 16px; padding-right: 16px; } .card-body { padding: 1.25rem; } h1, .h1 { font-size: 1.75rem; } .display-1 { font-size: 3rem; } }

/* ============ FIXED MOBILE HEADER ============ */
.navbar.fixed-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    min-height: 56px;
    position: sticky;
    top: 0;
    z-index: 1030;
}
.navbar.fixed-header .header-left {
    display: flex;
    align-items: center;
    flex: 0 0 auto;
    min-width: 44px;
}
.navbar.fixed-header .header-center {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    white-space: nowrap;
    font-weight: 700;
    font-size: 1.25rem;
    text-decoration: none;
    color: #fff;
}
.navbar.fixed-header .header-right {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex: 0 0 auto;
    min-width: 44px;
    justify-content: flex-end;
}
.navbar.fixed-header .hamburger-btn {
    background: none;
    border: none;
    color: #fff;
    font-size: 1.5rem;
    padding: 0.25rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
}
/* Side menu */
.side-menu {
    position: fixed;
    top: 0;
    left: -280px;
    width: 280px;
    height: 100vh;
    background: #fff;
    z-index: 1090;
    transition: left 0.3s ease;
    box-shadow: 2px 0 12px rgba(0,0,0,0.15);
    overflow-y: auto;
}
.side-menu.open { left: 0; }
.side-menu-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5);
    z-index: 1089;
    display: none;
}
.side-menu-overlay.open { display: block; }
.side-menu .menu-header {
    background: #0d6efd;
    color: #fff;
    padding: 1rem;
    font-weight: 700;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.side-menu .menu-section-title {
    padding: 0.75rem 1rem 0.25rem;
    font-size: 0.7rem;
    text-transform: uppercase;
    color: #6c757d;
    font-weight: 600;
    letter-spacing: 0.5px;
}
.side-menu .menu-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.6rem 1rem;
    color: #212529;
    text-decoration: none;
    font-size: 0.9rem;
    transition: background 0.15s;
}
.side-menu .menu-item:hover { background: #f0f4ff; }
.side-menu .menu-item i { width: 20px; text-align: center; font-size: 1rem; color: #6c757d; }
.side-menu .menu-divider { border-top: 1px solid #e9ecef; margin: 0.25rem 0; }

/* ============ PUBLIC HOMEPAGE MOBILE FIXES ============ */
@media (max-width: 576px) {
    .hero-section .display-6 { font-size: 1.5rem; }
    .hero-section .lead { font-size: 0.95rem; }
    .hero-search input { padding: 12px 16px; font-size: 0.95rem; }
    .hero-search button { padding: 0 16px; }
}

/* ============ READING PASSAGE STYLES (V3) ============ */
.reading-passage {
    font-size: 0.9rem;
    line-height: 1.7;
    max-height: 400px;
    overflow-y: auto;
}
.reading-passage .passage-text {
    white-space: pre-wrap;
}
.reading-passage .passage-full {
    white-space: pre-wrap;
}
.card-header.bg-primary.bg-opacity-10 {
    border-bottom: 2px solid rgba(13, 110, 253, 0.2);
}
.group-questions .card {
    border-left: 3px solid #0d6efd;
}
.group-questions .card:last-child {
    margin-bottom: 0 !important;
}