/* ═══════════════════════════════════════════════════════════════════
 *  GEII TOOLBOX — Shared UI primitives
 *  • App header (back-to-home + theme cycler) injected by app-header.js
 *  • Generic card / panel styles usable by every app
 *  • All colors flow through theme.css variables
 * ═══════════════════════════════════════════════════════════════════ */

/* ─── APP HEADER (shared across all apps) ─────────────────────────────
 * Positioned ABSOLUTELY at the top of the viewport so it overlays any
 * pre-existing app layout (Signal Observatory uses a row-flex body with
 * sidebar+main). Apps that have a full-height sidebar should expose a
 * --app-header-h custom property so their internal layout can reserve
 * space below — see signal-observatory's components.css.
 * ───────────────────────────────────────────────────────────────────── */
:root { --app-header-h: 36px; }

#geii-app-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 9999;
    display: flex;
    align-items: center;
    height: var(--app-header-h);
    padding: 0 14px;
    gap: 10px;
    background: linear-gradient(180deg,
        rgba(8, 8, 28, 0.85) 0%,
        rgba(5, 5, 20, 0.75) 100%);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--rim);
    font-family: 'Space Mono', monospace;
    font-size: 0.82rem;
    color: var(--text-mid);
    letter-spacing: 0.04em;
    flex-shrink: 0;
}

body.theme-amber #geii-app-header {
    background: linear-gradient(180deg, rgba(20, 12, 0, 0.9), rgba(15, 8, 0, 0.75));
}
body.theme-solarized #geii-app-header {
    background: linear-gradient(180deg, rgba(0, 43, 54, 0.92), rgba(7, 54, 66, 0.75));
}

#geii-app-header .gh-back {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px 10px;
    color: var(--text-bright);
    text-decoration: none;
    border: 1px solid var(--rim);
    border-radius: 4px;
    transition: background 120ms, border-color 120ms, transform 120ms;
}
#geii-app-header .gh-back:hover {
    background: var(--rim);
    border-color: var(--accent-blue);
    transform: translateX(-2px);
}

/* Mobile Responsive */
@media (max-width: 768px) {
    #sidebar {
        width: 100%;
        max-width: 100%;
        position: relative;
        border-right: none;
        border-bottom: 1px solid var(--rim);
        height: auto;
    }
    body {
        flex-direction: column;
    }
    .math-panel {
        position: relative;
        width: 100%;
        max-width: 100%;
        border-left: none;
        border-top: 1px solid var(--rim);
    }
}
#geii-app-header .gh-arrow {
    color: var(--accent-blue);
    font-size: 0.95rem;
    line-height: 1;
}
#geii-app-header .gh-back-label {
    font-weight: 600;
    letter-spacing: 0.12em;
}

#geii-app-header .gh-sep {
    width: 1px;
    height: 18px;
    background: var(--rim);
}

#geii-app-header .gh-app {
    display: inline-flex;
    align-items: baseline;
    gap: 10px;
    min-width: 0;
}
#geii-app-header .gh-icon {
    font-size: 1rem;
    line-height: 1;
}
#geii-app-header .gh-name {
    color: var(--text-glow);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    font-size: 0.88rem;
}
#geii-app-header .gh-tagline {
    color: var(--text-dim);
    font-size: 0.78rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 50ch;
}

#geii-app-header .gh-spacer { flex: 1; }

#geii-app-header .gh-theme {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    background: transparent;
    border: 1px solid var(--rim);
    border-radius: 4px;
    color: var(--text-bright);
    font-family: inherit;
    font-size: 0.80rem;
    letter-spacing: 0.08em;
    cursor: pointer;
    transition: background 120ms, border-color 120ms;
}
#geii-app-header .gh-theme:hover {
    background: var(--rim);
    border-color: var(--accent-cyan);
}
#geii-app-header .gh-theme-icon { font-size: 0.9rem; }

/* ─── SHARE BUTTON (URL state sync) ───────────────────────────────── */
#geii-app-header .gh-share {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    margin-right: 8px;
    background: transparent;
    border: 1px solid var(--rim);
    border-radius: 4px;
    color: var(--text-bright);
    font-family: inherit;
    font-size: 0.80rem;
    letter-spacing: 0.08em;
    cursor: pointer;
    transition: background 120ms, border-color 120ms, color 120ms;
}
#geii-app-header .gh-share:hover {
    background: var(--rim);
    border-color: var(--accent-cyan);
}
#geii-app-header .gh-share-icon { font-size: 0.9rem; }
#geii-app-header .gh-share.gh-share-ok {
    border-color: #4ade80;
    color: #4ade80;
}
#geii-app-header .gh-share.gh-share-err {
    border-color: #f87171;
    color: #f87171;
}

/* ─── GENERIC CARD ────────────────────────────────────────────────── */
.toolbox-card {
    background: rgba(13, 13, 40, 0.55);
    border: 1px solid var(--rim);
    border-radius: 8px;
    padding: 18px;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    transition: border-color 200ms, transform 200ms;
}
.toolbox-card:hover {
    border-color: var(--accent-blue);
}

/* ─── STUB PAGE (used by placeholder apps) ────────────────────────── */
.stub-page {
    flex: 1;
    min-height: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    position: relative;
    z-index: 10;
}
.stub-card {
    max-width: 640px;
    background: rgba(8, 8, 28, 0.85);
    border: 1px solid var(--rim-bright);
    border-radius: 14px;
    padding: 36px 40px;
    color: var(--text-bright);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.4);
}
.stub-card .stub-icon {
    font-size: 3rem;
    line-height: 1;
    color: var(--accent-gold);
    margin-bottom: 14px;
}
.stub-card h1 {
    margin: 0 0 6px 0;
    font-family: 'Inter', sans-serif;
    font-size: 1.6rem;
    color: var(--text-glow);
    letter-spacing: 0.02em;
}
.stub-card .stub-tagline {
    color: var(--text-mid);
    font-family: 'Space Mono', monospace;
    font-size: 0.85rem;
    letter-spacing: 0.06em;
    margin-bottom: 22px;
}
.stub-card .stub-status {
    display: inline-block;
    padding: 4px 10px;
    border-radius: 999px;
    border: 1px solid var(--accent-gold);
    color: var(--accent-gold);
    font-family: 'Space Mono', monospace;
    font-size: 0.80rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    margin-bottom: 22px;
}
.stub-card .stub-desc {
    color: var(--text-bright);
    line-height: 1.6;
    margin-bottom: 22px;
}
.stub-card h2 {
    font-size: 0.88rem;
    color: var(--text-mid);
    letter-spacing: 0.18em;
    text-transform: uppercase;
    margin: 18px 0 10px;
    font-family: 'Space Mono', monospace;
    font-weight: 500;
}
.stub-card ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.stub-card ul li {
    padding: 6px 0 6px 22px;
    position: relative;
    color: var(--text-bright);
    font-size: 0.88rem;
    border-bottom: 1px dashed var(--rim);
}
.stub-card ul li:last-child { border-bottom: none; }
.stub-card ul li::before {
    content: '▸';
    position: absolute;
    left: 4px;
    color: var(--accent-blue);
}
.stub-card .stub-matieres {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 10px;
}
.stub-card .stub-matiere {
    padding: 3px 9px;
    border-radius: 4px;
    background: var(--rim);
    color: var(--text-bright);
    font-family: 'Space Mono', monospace;
    font-size: 0.80rem;
    letter-spacing: 0.05em;
}
.stub-card .stub-cta {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-top: 22px;
    padding: 10px 18px;
    background: var(--accent-blue);
    color: var(--void);
    text-decoration: none;
    border-radius: 6px;
    font-family: 'Space Mono', monospace;
    font-size: 0.88rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    transition: transform 120ms, box-shadow 120ms;
}
.stub-card .stub-cta:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(79, 140, 255, 0.4);
}