/* Floating island site header — blends over hero, solid pill on scroll */

:root {
    --site-header-height: 4rem;
    --site-header-offset: calc(var(--site-header-height) + var(--site-header-pad, 0.85rem) * 2);
    --site-header-ease: cubic-bezier(0.22, 1, 0.36, 1);
    --site-header-max-width: 74rem;
    --site-header-gutter: 1rem;
    --site-header-inset-x: 0.625rem;
    --site-header-engine-trim: 0rem;
    --site-header-logo-height: 2.125rem;
    --site-header-logo-height-scrolled: 1.875rem;
    --site-header-nav-size: 1rem;
    --site-header-glass-bg: linear-gradient(
        145deg,
        rgba(255, 255, 255, 0.58) 0%,
        rgba(255, 255, 255, 0.34) 52%,
        rgba(248, 250, 252, 0.28) 100%
    );
    --site-header-glass-border: rgba(255, 255, 255, 0.68);
    --site-header-glass-blur: blur(22px) saturate(185%);
    --site-header-glass-shadow:
        inset 0 1px 1px rgba(255, 255, 255, 0.92),
        inset 0 -1px 0 rgba(255, 255, 255, 0.28),
        0 10px 36px -10px rgba(15, 23, 42, 0.16),
        0 4px 14px -4px rgba(15, 23, 42, 0.07);
}

@media (min-width: 1200px) {
    :root {
        --site-header-max-width: min(92rem, calc(100vw - 5.5rem));
        --site-header-gutter: 1.25rem;
        /* Match sidebar rail right edge (engine col is 26rem, sidebar uses 80%) */
        --site-header-engine-trim: 5.2rem;
    }
}

@media (min-width: 1400px) {
    :root {
        --site-header-max-width: min(96rem, calc(100vw - 5rem));
        --site-header-engine-trim: 5.6rem;
    }
}

body {
    --site-header-pad: 0.85rem;
}

body.blog-has-featured-hero:not(.is-scrolled),
body.blog-home-page:not(.is-scrolled) {
    --site-header-pad: 1.1rem;
}

body:not(.blog-has-featured-hero):not(.blog-home-page) {
    padding-top: var(--site-header-offset);
}

.blog-site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1100;
    padding: var(--site-header-pad) 0;
    pointer-events: none;
    transition: padding 0.45s var(--site-header-ease);
}

.blog-site-header__shell {
    width: 100%;
    max-width: var(--site-header-max-width);
    margin: 0 auto;
    padding: 0 var(--site-header-gutter);
    box-sizing: border-box;
    pointer-events: none;
}

/* Dark top vignette over hero — highlights logo/nav (theme: slate ink) */
body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 10.5rem;
    background: linear-gradient(
        180deg,
        rgba(15, 23, 42, 0.88) 0%,
        rgba(15, 23, 42, 0.58) 38%,
        rgba(15, 23, 42, 0.22) 62%,
        rgba(15, 23, 42, 0) 100%
    );
    pointer-events: none;
    z-index: -1;
    transition: opacity 0.5s var(--site-header-ease);
}

body.blog-has-featured-hero.is-scrolled .blog-site-header::before {
    opacity: 0;
}

body.is-scrolled .blog-site-header {
    padding-top: 0.55rem;
    padding-bottom: 0.55rem;
}

.blog-site-header__island {
    position: relative;
    isolation: isolate;
    pointer-events: auto;
    width: calc(100% - var(--site-header-engine-trim));
    max-width: 100%;
    margin: 0;
    box-sizing: border-box;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.85rem 1.5rem;
    min-height: var(--site-header-height);
    padding: 0.45rem var(--site-header-inset-x);
    border-radius: 999px;
    border: 1px solid transparent;
    background: transparent;
    box-shadow: none;
    transform: translateY(0);
    overflow: hidden;
    transition:
        background 0.45s var(--site-header-ease),
        border-color 0.45s var(--site-header-ease),
        box-shadow 0.45s var(--site-header-ease),
        transform 0.45s var(--site-header-ease),
        padding 0.45s var(--site-header-ease),
        backdrop-filter 0.45s var(--site-header-ease);
}

/* Frosted glass shine — visible when island is active */
.blog-site-header__island::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(
        165deg,
        rgba(255, 255, 255, 0.55) 0%,
        rgba(255, 255, 255, 0.08) 42%,
        transparent 62%
    );
    opacity: 0;
    pointer-events: none;
    z-index: 0;
    transition: opacity 0.45s var(--site-header-ease);
}

.blog-site-header__island > * {
    position: relative;
    z-index: 1;
}

/* Scrolled / default — frosted glass neomorphism */
body.is-scrolled .blog-site-header__island,
body:not(.blog-has-featured-hero):not(.blog-home-page) .blog-site-header__island,
body.blog-home-page.is-scrolled .blog-site-header__island {
    background: var(--site-header-glass-bg);
    border-color: var(--site-header-glass-border);
    box-shadow: var(--site-header-glass-shadow);
    backdrop-filter: var(--site-header-glass-blur);
    -webkit-backdrop-filter: var(--site-header-glass-blur);
    padding: 0.4rem var(--site-header-inset-x);
}

body.is-scrolled .blog-site-header__island::before,
body:not(.blog-has-featured-hero):not(.blog-home-page) .blog-site-header__island::before,
body.blog-home-page.is-scrolled .blog-site-header__island::before {
    opacity: 1;
}

body.is-scrolled .blog-site-header__island {
    transform: translateY(0);
    box-shadow:
        inset 0 1px 1px rgba(255, 255, 255, 0.95),
        inset 0 -1px 0 rgba(255, 255, 255, 0.32),
        0 14px 44px -12px rgba(15, 23, 42, 0.2),
        0 6px 18px -6px rgba(15, 23, 42, 0.09);
}

/* At top — fully blended, no island until scroll */
body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__island,
body.blog-home-page:not(.is-scrolled) .blog-site-header__island {
    background: transparent;
    border-color: transparent;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    box-shadow: none;
    padding: 0.45rem var(--site-header-inset-x);
    min-height: calc(var(--site-header-height) + 0.25rem);
}

body.blog-home-page:not(.is-scrolled) .blog-site-header__island::before {
    opacity: 0;
}

body.blog-has-featured-hero.is-scrolled .blog-site-header__island,
body.blog-home-page.is-scrolled .blog-site-header__island {
    animation: site-header-island-in 0.5s var(--site-header-ease) both;
}

@keyframes site-header-island-in {
    from {
        opacity: 0.85;
        transform: translateY(-6px) scale(0.985);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.blog-site-header__logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    text-decoration: none;
    line-height: 0;
}

.blog-site-header__logo img {
    display: block;
    height: var(--site-header-logo-height);
    width: auto;
    transition:
        filter 0.45s var(--site-header-ease),
        transform 0.45s var(--site-header-ease),
        height 0.45s var(--site-header-ease);
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__logo img {
    filter:
        brightness(0) invert(1)
        drop-shadow(0 2px 10px rgba(0, 0, 0, 0.55))
        drop-shadow(0 1px 4px rgba(0, 0, 0, 0.4));
}

body.is-scrolled .blog-site-header__logo img,
body:not(.blog-has-featured-hero):not(.blog-home-page) .blog-site-header__logo img,
body.blog-home-page.is-scrolled .blog-site-header__logo img {
    height: var(--site-header-logo-height-scrolled);
    filter: drop-shadow(0 1px 2px rgba(15, 23, 42, 0.12));
}

body.blog-home-page:not(.is-scrolled) .blog-site-header__logo img {
    height: var(--site-header-logo-height);
    filter: none;
}

.blog-site-header__nav {
    display: none;
    align-items: center;
    justify-content: flex-end;
    gap: 0.2rem;
    margin-left: auto;
    min-width: 0;
    padding: 0 0 0 0.75rem;
}

@media (min-width: 768px) {
    .blog-site-header__nav {
        display: flex;
    }
}

.blog-site-header__link {
    position: relative;
    padding: 0.5rem 1rem;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: var(--site-header-nav-size);
    font-weight: 600;
    letter-spacing: -0.01em;
    color: #334155;
    text-decoration: none;
    border-radius: 999px;
    white-space: nowrap;
    transition: color 0.25s ease, background 0.25s ease;
}

.blog-site-header__link:hover {
    color: #1d4ed8;
    background: rgba(37, 99, 235, 0.08);
}

.blog-site-header__link.is-active {
    color: #1d4ed8;
}

.blog-site-header__link.is-active::after {
    content: '';
    position: absolute;
    left: 50%;
    bottom: 0.28rem;
    width: 1.35rem;
    height: 2px;
    margin-left: -0.675rem;
    border-radius: 999px;
    background: #2563eb;
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__link {
    color: rgba(255, 255, 255, 0.94);
    text-shadow: 0 1px 6px rgba(0, 0, 0, 0.35);
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__link:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.12);
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__link.is-active::after {
    background: #fff;
    box-shadow: 0 0 8px rgba(255, 255, 255, 0.35);
}

.blog-site-header__actions {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    flex-shrink: 0;
}

.blog-site-header__menu-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
    border: 1px solid rgba(226, 232, 240, 0.9);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.9);
    cursor: pointer;
    transition: background 0.25s ease, border-color 0.25s ease, transform 0.2s ease, box-shadow 0.25s ease;
}

@media (min-width: 768px) {
    .blog-site-header__menu-btn {
        display: none;
    }
}

.blog-site-header__menu-icon {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 0.2rem;
    width: 1.125rem;
}

.blog-site-header__menu-icon span {
    display: block;
    height: 2px;
    width: 100%;
    border-radius: 999px;
    background: #334155;
    transition: background 0.25s ease;
}

.blog-site-header__menu-btn:hover {
    background: #fff;
    border-color: #bfdbfe;
    transform: scale(1.04);
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__menu-btn {
    background: rgba(255, 255, 255, 0.14);
    border-color: rgba(255, 255, 255, 0.28);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.25);
}

body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__menu-icon span {
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
}

body.is-scrolled .blog-site-header__menu-btn,
body:not(.blog-has-featured-hero):not(.blog-home-page) .blog-site-header__menu-btn,
body.blog-home-page.is-scrolled .blog-site-header__menu-btn {
    width: 2.375rem;
    height: 2.375rem;
    background: rgba(255, 255, 255, 0.42);
    border-color: rgba(255, 255, 255, 0.62);
    backdrop-filter: blur(14px) saturate(160%);
    -webkit-backdrop-filter: blur(14px) saturate(160%);
    box-shadow:
        inset 0 1px 0 rgba(255, 255, 255, 0.75),
        0 4px 12px -4px rgba(15, 23, 42, 0.12);
}

/* Hero extends under fixed header */
.blog-has-featured-hero .blog-post-hero--featured {
    margin-top: 0;
}

.blog-has-featured-hero .blog-post-hero-media {
    position: relative;
}

/* Image vignette — blends with header gradient on featured posts */
body.blog-has-featured-hero:not(.is-scrolled) .blog-post-hero-media::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(
        180deg,
        rgba(15, 23, 42, 0.45) 0%,
        rgba(15, 23, 42, 0.12) 42%,
        transparent 68%
    );
    pointer-events: none;
    z-index: 1;
    transition: opacity 0.5s var(--site-header-ease);
}

body.blog-has-featured-hero.is-scrolled .blog-post-hero-media::after {
    opacity: 0;
}

.blog-has-featured-hero .blog-post-hero-frame {
    max-height: min(62vh, 560px);
}

/* Category hero — stronger top vignette when header is transparent */
body.blog-has-featured-hero:not(.is-scrolled) .blog-cat-hero-overlay {
    background: linear-gradient(
        180deg,
        rgba(15, 23, 42, 0.92) 0%,
        rgba(15, 23, 42, 0.62) 28%,
        rgba(15, 23, 42, 0.72) 100%
    );
}

/* ===================================================================
   Mobile slide-out menu
   =================================================================== */

body.blog-menu-open {
    overflow: hidden;
}

.blog-mobile-menu {
    position: fixed;
    top: 0;
    right: 0;
    width: min(100%, 22.5rem);
    height: 100%;
    z-index: 1200;
    pointer-events: none;
    visibility: hidden;
}

.blog-mobile-menu.open {
    pointer-events: auto;
    visibility: visible;
}

.blog-mobile-menu__panel {
    height: 100%;
    background: #fff;
    box-shadow: -12px 0 40px rgba(15, 23, 42, 0.12);
    display: flex;
    flex-direction: column;
    transform: translateX(105%);
    transition: transform 0.38s var(--site-header-ease);
    overflow: hidden;
}

.blog-mobile-menu.open .blog-mobile-menu__panel {
    transform: translateX(0);
}

.blog-mobile-menu__head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--blog-border, #e2e8f0);
}

.blog-mobile-menu__brand img {
    display: block;
    height: 1.75rem;
    width: auto;
}

.blog-mobile-menu__close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    border: 1px solid var(--blog-border, #e2e8f0);
    border-radius: 999px;
    background: #f8fafc;
    color: #475569;
    cursor: pointer;
    transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

#closeSidebar.blog-mobile-menu__close {
    display: inline-flex;
    background: #f8fafc;
    border-radius: 999px;
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
}

.blog-mobile-menu__close:hover {
    background: #eff6ff;
    border-color: #bfdbfe;
    color: #1d4ed8;
}

.blog-mobile-menu__categories {
    padding: 1.25rem 1.25rem 0.5rem;
}

.blog-mobile-menu__label {
    margin: 0 0 0.75rem;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: #94a3b8;
}

.blog-mobile-menu__category-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.blog-mobile-menu__category {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 0.85rem 1rem;
    border-radius: 0.875rem;
    background: linear-gradient(135deg, #eff6ff 0%, #f8fafc 100%);
    border: 1px solid #dbeafe;
    color: #0f172a;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.blog-mobile-menu__category-main {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 0;
}

.blog-mobile-menu__category-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.125rem;
    height: 2.125rem;
    border-radius: 0.625rem;
    background: rgba(37, 99, 235, 0.12);
    color: #2563eb;
    flex-shrink: 0;
}

.blog-mobile-menu__category-arrow {
    flex-shrink: 0;
    stroke: #64748b;
}

.blog-mobile-menu__category:hover {
    background: #eff6ff;
    border-color: #93c5fd;
    transform: translateX(-2px);
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.12);
}

.blog-mobile-menu__category.is-active {
    background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
    border-color: #1d4ed8;
    color: #fff;
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.28);
}

.blog-mobile-menu__category.is-active .blog-mobile-menu__category-icon {
    background: rgba(255, 255, 255, 0.18);
    color: #fff;
}

.blog-mobile-menu__category.is-active .blog-mobile-menu__category-arrow {
    stroke: #fff;
}

.blog-mobile-menu__divider {
    height: 1px;
    margin: 0.75rem 1.25rem;
    background: var(--blog-border, #e2e8f0);
}

.blog-mobile-menu__links {
    flex: 1;
    overflow-y: auto;
    padding: 0.25rem 1.25rem 1rem;
}

.blog-mobile-menu__list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.blog-mobile-menu__list li + li {
    margin-top: 0.15rem;
}

.blog-mobile-menu__link {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    padding: 0.75rem 0.5rem;
    border-radius: 0.75rem;
    color: #334155;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    transition: background 0.2s ease, color 0.2s ease;
}

.blog-mobile-menu__icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.125rem;
    height: 2.125rem;
    border-radius: 0.625rem;
    background: #eff6ff;
    color: #2563eb;
    flex-shrink: 0;
    transition: background 0.2s ease, color 0.2s ease;
}

.blog-mobile-menu__link:hover {
    background: #f8fafc;
    color: #1d4ed8;
}

.blog-mobile-menu__link:hover .blog-mobile-menu__icon {
    background: #dbeafe;
    color: #1d4ed8;
}

.blog-mobile-menu__footer {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem 0.75rem;
    padding: 1rem 1.25rem 1.35rem;
    border-top: 1px solid var(--blog-border, #e2e8f0);
    background: #f8fafc;
}

.blog-mobile-menu__footer-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 0.9375rem;
    font-weight: 600;
    color: #475569;
    text-decoration: none;
}

.blog-mobile-menu__footer-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: #2563eb;
}

.blog-mobile-menu__footer-link:hover {
    color: #1d4ed8;
}

.blog-mobile-menu__footer-dot {
    width: 4px;
    height: 4px;
    border-radius: 999px;
    background: #cbd5e1;
}

.blog-mobile-menu__badge {
    margin-left: auto;
    padding: 0.2rem 0.55rem;
    border-radius: 999px;
    background: #dbeafe;
    color: #1d4ed8;
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.04em;
}

@media (max-width: 480px) {
    .blog-mobile-menu {
        width: 100%;
    }
}

@media (min-width: 768px) {
    .blog-mobile-menu {
        display: none;
    }
}

@media (max-width: 767px) {
    :root {
        --site-header-logo-height: 1.875rem;
        --site-header-logo-height-scrolled: 1.65rem;
        --site-header-height: 3.5rem;
        --site-header-offset: calc(var(--site-header-height) + 0.95rem);
        --site-header-engine-trim: 0rem;
    }

    body.blog-has-featured-hero:not(.is-scrolled),
    body.blog-home-page:not(.is-scrolled) {
        --site-header-pad: 0.85rem;
    }

    .blog-site-header {
        padding-top: var(--site-header-pad);
        padding-bottom: var(--site-header-pad);
    }

    body.is-scrolled .blog-site-header {
        padding-top: 0.45rem;
        padding-bottom: 0.45rem;
    }

    .blog-site-header__shell {
        padding: 0 0.75rem;
    }

    .blog-site-header__island {
        width: 100%;
        padding-left: var(--site-header-inset-x);
        padding-right: var(--site-header-inset-x);
        gap: 0.5rem;
    }

    body.is-scrolled .blog-site-header__island,
    body:not(.blog-has-featured-hero) .blog-site-header__island,
    body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header__island {
        padding-left: var(--site-header-inset-x);
        padding-right: var(--site-header-inset-x);
    }

    body:not(.blog-has-featured-hero):not(.blog-home-page) {
        padding-top: var(--site-header-offset);
    }

    body.blog-has-featured-hero:not(.is-scrolled) .blog-site-header::before {
        height: 8.5rem;
    }

    /* Home: compact frosted bar on mobile — logo never overlaps hero copy */
    body.blog-home-page:not(.is-scrolled) .blog-site-header__island {
        background: var(--site-header-glass-bg);
        border-color: var(--site-header-glass-border);
        box-shadow: var(--site-header-glass-shadow);
        backdrop-filter: var(--site-header-glass-blur);
        -webkit-backdrop-filter: var(--site-header-glass-blur);
        min-height: var(--site-header-height);
        padding: 0.35rem var(--site-header-inset-x);
    }

    body.blog-home-page:not(.is-scrolled) .blog-site-header__island::before {
        opacity: 1;
    }

    body.blog-home-page:not(.is-scrolled) .blog-site-header__logo img {
        height: var(--site-header-logo-height-scrolled);
        filter: drop-shadow(0 1px 2px rgba(15, 23, 42, 0.12));
    }

    body.blog-home-page:not(.is-scrolled) .blog-site-header__menu-btn {
        background: rgba(255, 255, 255, 0.72);
        border-color: rgba(226, 232, 240, 0.95);
        color: #334155;
    }

    body.blog-home-page:not(.is-scrolled) .blog-site-header__menu-icon span {
        background: #334155;
        box-shadow: none;
    }
}

@media (prefers-reduced-motion: reduce) {
    .blog-site-header,
    .blog-site-header::before,
    .blog-site-header__island,
    .blog-site-header__logo img,
    .blog-site-header__link,
    .blog-site-header__island::before,
    .blog-site-header__menu-btn,
    .blog-post-hero-media::after,
    .blog-mobile-menu__panel,
    .blog-mobile-menu__category {
        transition: none;
        animation: none;
    }
}