/* =============================================================================
   themes.css — the luxe theme picker + glassmorphism polish.

   Loaded globally (right after tokens.css) so the theme menu is available on
   every page, public and app alike. The picker is wired by theme.js using
   classes/data-attributes only — no IDs — so the fragment can be included
   several times per page (header + footer) without collisions.

   Glassmorphism is applied as a progressive enhancement inside
   @supports(backdrop-filter) so browsers without it keep the solid fallbacks.
   ========================================================================== */

/* ---------------------------------------------------------------------------
   1. Theme menu trigger
   --------------------------------------------------------------------------- */
.theme-menu {
    position: relative;
    display: inline-flex;
}

.theme-menu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--glass-bg-strong);
    color: var(--text);
    cursor: pointer;
    box-shadow: var(--shadow-sm);
    transition:
        transform 0.25s ease,
        box-shadow 0.25s ease,
        border-color 0.25s ease;
}

.theme-menu-toggle .swatch-icon {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-gradient);
    box-shadow: 0 0 0 2px var(--glass-border), 0 2px 8px var(--glow);
    transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.theme-menu-toggle:hover {
    transform: translateY(-1px);
    border-color: var(--border-strong);
    box-shadow: var(--shadow-md), 0 0 0 4px var(--primary-soft);
}

.theme-menu-toggle:hover .swatch-icon {
    transform: scale(1.12) rotate(25deg);
}

.theme-menu-toggle[aria-expanded="true"] {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px var(--primary-soft);
}

.theme-menu-toggle:focus-visible {
    outline: 2px solid var(--ring);
    outline-offset: 3px;
}

/* ---------------------------------------------------------------------------
   2. Theme menu panel (glass card)
   --------------------------------------------------------------------------- */
.theme-menu-panel {
    position: absolute;
    top: calc(100% + 0.6rem);
    inset-inline-end: 0;
    z-index: 1200;
    width: 264px;
    padding: 1rem;
    border-radius: var(--radius-xl);
    border: 1px solid var(--glass-border);
    background: var(--glass-bg-strong);
    box-shadow: var(--glass-shadow);
    backdrop-filter: saturate(160%) blur(var(--glass-blur));
    -webkit-backdrop-filter: saturate(160%) blur(var(--glass-blur));
    transform-origin: top right;
    animation: theme-menu-in 0.18s ease;
}

@keyframes theme-menu-in {
    from { opacity: 0; transform: translateY(-6px) scale(0.97); }
    to   { opacity: 1; transform: translateY(0) scale(1); }
}

.theme-menu-panel[hidden] {
    display: none;
}

/* The footer sits at the viewport bottom, so its picker opens upward. */
.footer .theme-menu-panel {
    top: auto;
    bottom: calc(100% + 0.6rem);
    transform-origin: bottom right;
}

.theme-menu-title {
    margin: 0 0 0.6rem;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
}

/* ---------------------------------------------------------------------------
   3. Light / dark segmented control
   --------------------------------------------------------------------------- */
.theme-mode {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.25rem;
    padding: 0.25rem;
    border-radius: var(--radius);
    background: var(--surface-2);
    margin-bottom: 1rem;
}

.theme-mode-btn {
    border: none;
    background: transparent;
    color: var(--text-muted);
    padding: 0.45rem 0.5rem;
    border-radius: calc(var(--radius) - 3px);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    transition: background-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
}

.theme-mode-btn i {
    font-size: 0.85rem;
}

.theme-mode-btn[aria-pressed="true"] {
    background: var(--surface);
    color: var(--text);
    box-shadow: var(--shadow-sm);
}

.theme-mode-btn:hover {
    color: var(--text);
}

.theme-mode-btn:focus-visible {
    outline: 2px solid var(--ring);
    outline-offset: 2px;
}

/* ---------------------------------------------------------------------------
   4. Palette swatch grid
   --------------------------------------------------------------------------- */
.theme-palettes {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}

.palette-swatch {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    padding: 0.55rem 0.6rem;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    font-size: 0.82rem;
    font-weight: 600;
    cursor: pointer;
    transition:
        border-color 0.2s ease,
        box-shadow 0.2s ease,
        transform 0.2s ease,
        background-color 0.2s ease;
}

.palette-swatch:hover {
    transform: translateY(-1px);
    border-color: var(--border-strong);
    box-shadow: var(--shadow-sm);
}

.palette-swatch[aria-pressed="true"] {
    border-color: var(--primary);
    background: var(--primary-soft);
    box-shadow: 0 0 0 1px var(--primary) inset;
}

.palette-swatch:focus-visible {
    outline: 2px solid var(--ring);
    outline-offset: 2px;
}

.palette-swatch .swatch-dot {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
    border-radius: 50%;
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.35), 0 1px 4px rgba(15, 23, 28, 0.25);
}

.palette-swatch[data-swatch="emerald"] .swatch-dot {
    background: linear-gradient(135deg, #2a6a63 0%, #17463d 100%);
}
.palette-swatch[data-swatch="ocean"] .swatch-dot {
    background: linear-gradient(135deg, #2a7bb0 0%, #16496b 100%);
}
.palette-swatch[data-swatch="rose"] .swatch-dot {
    background: linear-gradient(135deg, #c65a85 0%, #8c3456 100%);
}
.palette-swatch[data-swatch="gold"] .swatch-dot {
    background: linear-gradient(135deg, #c8902f 0%, #8a5515 100%);
}

/* ---------------------------------------------------------------------------
   5. Glassmorphism polish (progressive enhancement)
   --------------------------------------------------------------------------- */
@supports (backdrop-filter: blur(1px)) {
    .header {
        background-color: var(--glass-bg-strong);
        backdrop-filter: saturate(160%) blur(var(--glass-blur));
        -webkit-backdrop-filter: saturate(160%) blur(var(--glass-blur));
    }

    .sidebar {
        background-color: var(--glass-bg-strong);
        backdrop-filter: saturate(160%) blur(var(--glass-blur));
        -webkit-backdrop-filter: saturate(160%) blur(var(--glass-blur));
    }

    .footer {
        background-color: var(--glass-bg);
        backdrop-filter: saturate(140%) blur(var(--glass-blur));
        -webkit-backdrop-filter: saturate(140%) blur(var(--glass-blur));
    }
}

/* Rich gradient on primary actions — the "luxe" signature. */
.btn-primary {
    background-image: var(--primary-gradient);
    background-size: 160% 160%;
    box-shadow: 0 4px 14px var(--glow);
}

.btn-primary:hover {
    background-position: 100% 50%;
    box-shadow: 0 8px 22px var(--glow);
}

/* Soft glow lift on interactive cards. */
.article-card,
.book-card,
.ebook-card,
.class-card {
    transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.article-card:hover,
.book-card:hover,
.ebook-card:hover,
.class-card:hover {
    box-shadow: 0 14px 40px var(--glow);
    border-color: var(--primary);
}

/* ---------------------------------------------------------------------------
   6. Theme-change cross-fade
   --------------------------------------------------------------------------- */
.theme-changing,
.theme-changing * {
    transition:
        background-color 0.3s ease,
        color 0.3s ease,
        border-color 0.3s ease,
        box-shadow 0.3s ease,
        fill 0.3s ease !important;
}

/* ---------------------------------------------------------------------------
   7. Reduced motion
   --------------------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
    .theme-menu-toggle .swatch-icon,
    .theme-menu-panel,
    .theme-mode-btn,
    .palette-swatch {
        animation: none !important;
        transition: none !important;
    }
}