:root{
    --portal-bg-0:#0b1020;
    --portal-bg-1:#070a14;
    --portal-surface:rgba(255,255,255,.06);
    --portal-surface-2:rgba(255,255,255,.10);
    --portal-border:rgba(255,255,255,.12);
    --portal-text:rgba(255,255,255,.92);
    --portal-muted:rgba(255,255,255,.62);
    --portal-accent:#8b5cf6;
    --portal-accent-2:#22d3ee;
    --portal-shadow: 0 12px 40px rgba(0,0,0,.45);
    --portal-radius: 18px;
}

html, body{
    height: 100%;
    overflow: hidden;
    background: radial-gradient(1200px 800px at 12% 10%, rgba(139,92,246,.22), transparent 55%),
                radial-gradient(1000px 700px at 88% 18%, rgba(34,211,238,.18), transparent 52%),
                linear-gradient(180deg, var(--portal-bg-0), var(--portal-bg-1));
    color: var(--portal-text);
}

/* subtle animated grain */
body::before{
    content:"";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(circle at 20% 30%, rgba(255,255,255,.06), transparent 35%),
        radial-gradient(circle at 70% 60%, rgba(255,255,255,.05), transparent 40%),
        repeating-linear-gradient(0deg, rgba(255,255,255,.02), rgba(255,255,255,.02) 1px, transparent 1px, transparent 3px);
    mix-blend-mode: overlay;
    opacity: .22;
}

.portal-shell{
    height: 100vh;
    overflow: hidden;
    padding: 18px;
    gap: 16px;
}

.sidebar{
    width: 280px;
    height: calc(100vh - 36px);
    border-radius: var(--portal-radius);
    background: linear-gradient(180deg, rgba(255,255,255,.10), rgba(255,255,255,.06));
    border: 1px solid var(--portal-border);
    box-shadow: var(--portal-shadow);
    backdrop-filter: blur(14px);
}

.sidebar .portal-brand{
    letter-spacing: .2px;
    color: var(--portal-text);
}

.portal-section-title{
    font-size: .78rem;
    text-transform: uppercase;
    letter-spacing: .12em;
    color: var(--portal-muted);
}

.sidebar .list-group{
    --bs-list-group-bg: transparent;
    --bs-list-group-border-color: transparent;
}

.sidebar .list-group-item{
    border: 0;
    border-radius: 12px;
    margin: 2px 10px;
    padding: .6rem .75rem;
    background: transparent;
    color: var(--portal-text);
    display: flex;
    align-items: center;
    gap: .6rem;
    transition: transform .12s ease, background-color .12s ease, box-shadow .12s ease;
}
.sidebar .list-group-item:hover{
    background: rgba(255,255,255,.10);
    transform: translateY(-1px);
}
.sidebar .list-group-item.active,
.sidebar .list-group-item.active:focus{
    background: linear-gradient(135deg, rgba(139,92,246,.35), rgba(34,211,238,.22));
    box-shadow: 0 8px 24px rgba(139,92,246,.18);
}

.portal-main{
    height: calc(100vh - 36px);
    border-radius: var(--portal-radius);
    border: 1px solid var(--portal-border);
    background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,.05));
    box-shadow: var(--portal-shadow);
    backdrop-filter: blur(14px);
    overflow: hidden;
}

.portal-topbar{
    background: transparent !important;
    border-bottom: 1px solid var(--portal-border);
}
.portal-topbar .navbar-brand{
    color: var(--portal-text);
}
.portal-topbar .nav-muted{
    color: var(--portal-muted);
}

.main-content{
    flex-grow: 1;
    overflow: hidden;
    padding: 0;
}
.main-content iframe{
    display: block;
    width: 100%;
    height: calc(100vh - 36px - 62px);
    border: none;
    background: white;
}

/* Bootstrap overrides for dark glass theme */
.btn.btn-outline-secondary{
    --bs-btn-color: var(--portal-text);
    --bs-btn-border-color: rgba(255,255,255,.24);
    --bs-btn-hover-bg: rgba(255,255,255,.10);
    --bs-btn-hover-border-color: rgba(255,255,255,.28);
}

.btn-portal{
    background: linear-gradient(135deg, rgba(139,92,246,.95), rgba(34,211,238,.85));
    border: 0;
    color: #0b1020;
    font-weight: 700;
    box-shadow: 0 10px 26px rgba(139,92,246,.20);
}

.portal-pill{
    border: 1px solid rgba(255,255,255,.18);
    background: rgba(255,255,255,.08);
    border-radius: 999px;
    padding: .35rem .6rem;
}

@media (max-width: 991.98px){
    html, body{ overflow: auto; }
    .portal-shell{
        height: auto;
        padding: 12px;
    }
    .portal-main{
        height: auto;
        min-height: 70vh;
    }
    .main-content iframe{
        height: 70vh;
    }
}