/* ============================================================
   SHARED PAGE NAV COMPONENT
   Canonical floating menu skin for all project pages
   ============================================================ */

:root {
    --floating-control-side: calc(80px + var(--safe-left, 0px));
    --floating-control-side-mobile: calc(16px + var(--safe-left, 0px));
    --floating-control-bottom: calc(32px + var(--safe-bottom, 0px));
    --floating-control-bottom-mobile: calc(88px + var(--safe-bottom, 0px));
    --floating-menu-side: calc(80px + var(--safe-right, 0px));
    --floating-menu-top-mobile: calc(16px + var(--safe-top, 0px));
    --floating-control-size-mobile: 48px;
    --floating-control-accent: var(--page-accent, var(--c-accent));
}

.back-btn {
    position: fixed !important;
    bottom: var(--floating-control-bottom) !important;
    left: var(--floating-control-side) !important;
    top: auto !important;
    right: auto !important;
    z-index: 1000;
    --btn-accent: var(--floating-control-accent);
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    gap: 10px !important;
    min-height: 48px;
    padding: 12px 20px !important;
    margin: 0 !important;
    border-radius: var(--radius-pill) !important;
    color: var(--c-text) !important;
    font-size: 14px !important;
    font-weight: 700 !important;
    line-height: 1 !important;
    text-decoration: none !important;
    white-space: nowrap !important;
    background: rgba(20, 20, 20, 0.68) !important;
    -webkit-backdrop-filter: blur(22px) saturate(1.35) !important;
    backdrop-filter: blur(22px) saturate(1.35) !important;
    border: 1px solid color-mix(in srgb, var(--btn-accent) 30%, rgba(255,255,255,0.1)) !important;
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.28),
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.08),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.04) !important;
    overflow: hidden !important;
    isolation: isolate;
    transition:
        background 0.3s var(--ease-out),
        border-color 0.3s var(--ease-out),
        box-shadow 0.3s var(--ease-out),
        transform 0.3s var(--ease-out) !important;
}

.back-btn::before {
    content: "" !important;
    position: absolute !important;
    inset: 0 !important;
    border-radius: inherit !important;
    background: var(--btn-accent) !important;
    opacity: 0.16 !important;
    pointer-events: none !important;
    z-index: 0 !important;
    transition: opacity 0.3s var(--ease-out) !important;
}

.back-btn::after {
    content: "" !important;
    position: absolute !important;
    inset: 0 !important;
    border-radius: inherit !important;
    background: rgba(0, 0, 0, 0.1) !important;
    box-shadow:
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.1),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.04) !important;
    opacity: 1 !important;
    pointer-events: none !important;
    z-index: 1 !important;
    transition: background 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out) !important;
}

.back-btn:hover {
    background: rgba(20, 20, 20, 0.84) !important;
    border-color: color-mix(in srgb, var(--btn-accent) 72%, rgba(255,255,255,0.18)) !important;
    transform: translateY(-2px);
    box-shadow:
        0 12px 30px rgba(0, 0, 0, 0.34),
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.12),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.06) !important;
}

.back-btn:hover::before {
    opacity: 0.38 !important;
}

.back-btn:hover::after {
    background: rgba(0, 0, 0, 0.16) !important;
}

.back-btn:active {
    transform: translateY(0);
}

.back-btn i,
.back-btn span {
    position: relative !important;
    z-index: 2 !important;
}

.shared-site-nav-active .svc-nav {
    display: none !important;
}

.page-nav {
    position: fixed !important;
    bottom: var(--floating-control-bottom) !important;
    right: var(--floating-menu-side) !important;
    top: auto !important;
    left: auto !important;
    z-index: 1000;
    width: fit-content !important;
    min-width: 0 !important;
    max-width: min(calc(100vw - 32px), var(--page-nav-closed-max, 360px)) !important;
    --btn-accent: var(--c-accent);
    background: rgba(20, 20, 20, 0.6);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border: 1px solid color-mix(in srgb, var(--btn-accent) 25%, rgba(255,255,255,0.08));
    box-shadow:
        0 4px 12px rgba(0, 0, 0, 0.15),
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.06),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.03);
    max-height: 48px;
    border-radius: var(--radius-pill);
    overflow: hidden;
    opacity: 0;
    filter: blur(8px);
    pointer-events: none;
    display: flex;
    flex-direction: column-reverse;
    transition:
        max-height 0.45s cubic-bezier(0.4, 0, 0.2, 1),
        min-width 0.4s cubic-bezier(0.4, 0, 0.2, 1),
        border-radius 0.35s cubic-bezier(0.4, 0, 0.2, 1),
        background 0.3s var(--ease-out),
        box-shadow 0.3s var(--ease-out),
        border-color 0.3s var(--ease-out),
        opacity 0.6s var(--ease-out),
        filter 0.6s var(--ease-out),
        transform 0.4s var(--ease-out);
    will-change: max-height, min-width, border-radius;
}

.page-nav.visible {
    opacity: 1;
    filter: blur(0);
    pointer-events: all;
}

.page-nav::before {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--btn-accent);
    opacity: 0.15;
    pointer-events: none;
    transition: opacity 0.4s var(--ease-out);
    z-index: 0;
    border-radius: inherit;
}

.page-nav::after {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.1);
    pointer-events: none;
    z-index: 1;
    border-radius: inherit;
    box-shadow:
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.08),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.04);
}

.page-nav:not(.open):hover {
    background: rgba(20, 20, 20, 0.8);
    border-color: var(--btn-accent);
    transform: translateY(-2px);
    box-shadow:
        0 8px 24px rgba(0, 0, 0, 0.25),
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.1),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.05);
}

.page-nav:not(.open):hover::before {
    opacity: 0.4;
}

.page-nav.open {
    max-height: var(--expanded-height, 400px);
    min-width: min(var(--page-nav-open-width, 304px), calc(100vw - 32px)) !important;
    max-width: calc(100vw - 32px) !important;
    border-radius: var(--radius);
    background: rgba(20, 20, 20, 0.95);
    -webkit-backdrop-filter: blur(30px);
    backdrop-filter: blur(30px);
    box-shadow:
        0 8px 32px rgba(0, 0, 0, 0.4),
        inset 2px 2px 1px 0 rgba(255, 255, 255, 0.06),
        inset -1px -1px 1px 1px rgba(255, 255, 255, 0.03);
    transition:
        max-height 0.5s cubic-bezier(0.34, 1.56, 0.64, 1),
        min-width 0.45s cubic-bezier(0.34, 1.56, 0.64, 1),
        border-radius 0.35s cubic-bezier(0.34, 1.56, 0.64, 1),
        background 0.3s var(--ease-out),
        box-shadow 0.3s var(--ease-out),
        border-color 0.3s var(--ease-out),
        opacity 0.6s var(--ease-out),
        filter 0.6s var(--ease-out),
        transform 0.4s var(--ease-out);
}

.page-nav.open::before {
    opacity: 0.1;
}

.page-nav.closing {
    pointer-events: none;
}

.page-nav.closing .page-nav-body::before,
.page-nav.closing .page-menu-item,
.page-nav.closing .page-menu-section-header,
.page-nav.closing .page-menu-divider {
    opacity: 0 !important;
    transform: translateY(6px) !important;
    transition: opacity 0.15s var(--ease-out), transform 0.15s var(--ease-out) !important;
    transition-delay: 0ms !important;
}

.page-nav-header {
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    gap: 10px !important;
    width: 100% !important;
    min-height: 48px;
    padding: 10px 18px !important;
    position: relative;
    z-index: 2;
    cursor: pointer;
    white-space: nowrap;
    user-select: none;
    -webkit-user-select: none;
    box-sizing: border-box;
    text-align: center;
}

.page-nav-header i,
.page-nav-header img,
.page-nav-header span {
    position: relative;
    z-index: 2;
}

.page-nav-header > span {
    flex: 0 1 auto;
    line-height: 1.05;
    min-width: 0;
}

.page-title-icon,
.page-nav-header > i:not(.page-title-chevron) {
    width: 18px !important;
    height: 18px !important;
    flex: 0 0 18px;
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    object-fit: contain;
    opacity: 0.95;
}

.page-title-icon.invert-logo,
.page-menu-item-icon.invert-logo,
.page-menu-item-icon img.invert-logo {
    filter: invert(1) brightness(1.2);
}

.page-nav-header > i:not(.page-title-chevron) {
    color: var(--c-accent);
}

.page-title-chevron {
    font-size: 12px !important;
    line-height: 1;
    margin-left: 2px !important;
    color: var(--c-text);
    flex: 0 0 auto;
    transition: transform 0.3s var(--ease-out);
}

.page-nav.open .page-title-chevron {
    transform: rotate(180deg);
}

.page-nav-body {
    position: relative;
    z-index: 2;
    padding: 6px 10px 10px !important;
    overflow-y: auto;
    max-height: calc(60vh - 48px);
}

.page-nav-body::before {
    content: "";
    position: sticky;
    top: 0;
    left: 0;
    display: block;
    width: 100%;
    height: 0;
    background: transparent;
    z-index: 3;
    pointer-events: none;
}

.page-menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 14px;
    border-radius: 14px;
    color: var(--c-text);
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    transition:
        background 0.25s var(--ease-out),
        transform 0.25s var(--ease-out),
        opacity 0.25s var(--ease-out);
    position: relative;
    opacity: 0;
    transform: translateY(8px);
    transition-delay: calc(var(--item-index, 0) * 30ms);
}

.page-nav.open .page-menu-item,
.page-nav.open .page-menu-section-header,
.page-nav.open .page-menu-divider {
    opacity: 1;
    transform: translateY(0);
    transition-delay: calc(120ms + var(--item-index, 0) * 30ms);
}

.page-menu-item:hover {
    background: rgba(255, 255, 255, 0.06);
}

.page-menu-item.active {
    background: color-mix(in srgb, var(--btn-accent) 16%, rgba(255,255,255,0.04));
}

.page-menu-item-icon {
    width: 20px;
    height: 20px;
    flex: 0 0 20px;
    object-fit: contain;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.page-menu-item-text {
    flex: 1;
    min-width: 0;
    line-height: 1.2;
}

.page-menu-item-arrow {
    flex: 0 0 auto;
    font-size: 12px;
    opacity: 0.7;
}

.page-menu-section-header {
    padding: 12px 14px 8px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--c-text-muted);
    opacity: 0;
    transform: translateY(8px);
    transition:
        opacity 0.25s var(--ease-out),
        transform 0.25s var(--ease-out);
}

.page-menu-divider {
    height: 1px;
    margin: 8px 0;
    background: linear-gradient(to right, transparent, rgba(255,255,255,0.1), transparent);
    opacity: 0;
    transform: translateY(8px);
    transition:
        opacity 0.25s var(--ease-out),
        transform 0.25s var(--ease-out);
}

@media (max-width: 768px) {
    .page-nav {
        top: var(--floating-menu-top-mobile) !important;
        bottom: auto !important;
        left: 50% !important;
        right: auto !important;
        transform: translateX(-50%);
        flex-direction: column;
        max-width: calc(100vw - 24px) !important;
    }

    .page-nav.visible {
        transform: translateX(-50%);
    }

    .page-nav:not(.open):hover {
        transform: translateX(-50%) translateY(-2px);
    }

    .page-nav.open {
        min-width: min(var(--page-nav-open-width, 320px), calc(100vw - 24px)) !important;
        max-width: calc(100vw - 24px) !important;
        transform: translateX(-50%);
    }

    .page-nav-header {
        min-height: 44px;
        padding: 10px 16px !important;
        font-size: 13px;
        gap: 8px !important;
    }

    .page-nav.open .page-nav-header {
        padding-left: 16px !important;
        padding-right: 16px !important;
    }

    .back-btn {
        bottom: var(--floating-control-bottom-mobile) !important;
        left: var(--floating-control-side-mobile) !important;
        width: var(--floating-control-size-mobile) !important;
        min-width: var(--floating-control-size-mobile) !important;
        height: var(--floating-control-size-mobile) !important;
        min-height: var(--floating-control-size-mobile) !important;
        padding: 0 !important;
        gap: 0 !important;
        font-size: 0 !important;
    }

    .back-btn i {
        font-size: 19px !important;
        line-height: 1 !important;
    }

    .back-btn span {
        display: none !important;
    }
}