/*
 * Layout System: CSS Grid containers, responsive breakpoints
 * Mobile-first approach: base styles for mobile, then scale up
 */

/* === Reset & Base === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height);
    color: var(--color-text);
    background-color: var(--color-bg);
    min-height: 100vh;
    /* Prevent layout shift when scrollbar appears/disappears */
    overflow-y: scroll;
}

/* === Links === */
a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-fast);
}
a:hover {
    color: var(--color-accent-hover);
}

/* === Images === */
img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* === Lists === */
ul, ol {
    list-style: none;
}

/* === Container === */
/* Centered content wrapper with responsive padding */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.container--narrow {
    max-width: var(--container-narrow);
}

/* === Site Layout === */
/* Fixed header + scrollable content + footer */
.site-header {
    position: sticky;
    top: 0;
    z-index: var(--z-header);
    height: var(--header-height);
    background: var(--color-bg-elevated);
    border-bottom: 1px solid var(--color-border);
}

.site-main {
    min-height: calc(100vh - var(--header-height) - 200px); /* Ensure footer stays low */
    min-height: calc(100svh - var(--header-height) - 200px); /* iOS Safari: small viewport height excludes address bar, preventing content from being hidden under it */
    padding: var(--space-xl) 0;
}

.site-footer {
    background: var(--color-bg-elevated);
    border-top: 1px solid var(--color-border);
    padding: var(--space-2xl) 0 var(--space-lg);
}

/* === Header Internal Layout === */
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: var(--space-md);
    min-width: 0;
}

.site-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 22px;
    font-weight: var(--weight-bold);
    color: var(--color-text);
    flex: 1 1 auto;
    min-width: 0;
    max-width: min(52vw, 360px);
    white-space: nowrap;
    overflow: hidden;
}
.site-logo:hover {
    color: var(--color-accent);
}
.site-logo__mark {
    width: 12px;
    height: 12px;
    border-radius: var(--radius-full);
    background: var(--accent);
    box-shadow: 0 0 12px rgba(255, 77, 77, 0.55);
    flex: 0 0 auto;
}
.site-logo__text {
    display: block;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
}
.site-logo__img {
    width: auto;
    max-width: 100%;
    max-height: 40px;
    object-fit: contain;
}

/* Main navigation - hamburger on phones, visible navigation on tablet/desktop */
.main-nav {
    display: none; /* Hidden on mobile, shown via JS toggle */
}
.main-nav.is-open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-bg-elevated);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md);
    z-index: var(--z-dropdown);
    /* Requirement: phone menus must remain inside the visible viewport when navigation is long.
       Approach: keep the existing full-width accordion below the sticky header and scroll its contents independently. */
    max-height: calc(100vh - var(--header-height));
    max-height: calc(100svh - var(--header-height));
    overflow-y: auto;
    overscroll-behavior: contain;
}
.main-nav a {
    color: var(--color-text-secondary);
    padding: var(--space-sm) 0;
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
}
.main-nav a:hover,
.main-nav a.active {
    color: var(--color-accent);
}

/* === Navigation Dropdown Menus === */
/* Dropdown container — holds trigger link + expandable panel */
.nav-dropdown {
    position: relative;
}
/* Trigger: top-level link or label-only button with inline chevron arrow */
.nav-dropdown__trigger {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    background: none;
    border: 0;
    color: var(--color-text-secondary);
    font: inherit;
    padding: var(--space-sm) 0;
    cursor: pointer;
}
.nav-dropdown__trigger:hover,
.nav-dropdown__trigger.active {
    color: var(--color-accent);
}
/* Chevron arrow — rotates 180° when dropdown opens */
.nav-dropdown__chevron {
    opacity: 0.5;
    flex-shrink: 0;
    transition: transform var(--transition-fast), opacity var(--transition-fast);
}
/* Panel: absolutely positioned below trigger, hidden by default */
.nav-dropdown__panel {
    position: absolute;
    top: calc(100% + 8px);
    left: 0;
    min-width: 160px;
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--card-radius);
    box-shadow: var(--shadow-lg);
    padding: var(--space-xs) 0;
    z-index: var(--z-dropdown);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-4px);
    transition: opacity var(--transition-fast), transform var(--transition-fast), visibility var(--transition-fast);
}
/* Invisible hover bridge between trigger and panel */
.nav-dropdown__panel::before {
    content: '';
    position: absolute;
    top: -8px;
    left: 0;
    right: 0;
    height: 8px;
}
/* Show panel on hover (desktop) or .is-open (mobile/touch) */
.nav-dropdown:hover .nav-dropdown__panel,
.nav-dropdown:focus-within .nav-dropdown__panel,
.nav-dropdown.is-open .nav-dropdown__panel {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.nav-dropdown:hover .nav-dropdown__chevron,
.nav-dropdown:focus-within .nav-dropdown__chevron,
.nav-dropdown.is-open .nav-dropdown__chevron {
    transform: rotate(180deg);
    opacity: 0.8;
}
/* Dropdown items — higher specificity to override .main-nav a padding */
.nav-dropdown__panel .nav-dropdown__item {
    display: block;
    padding: var(--space-sm) var(--space-md);
    white-space: nowrap;
}
.nav-dropdown__panel .nav-dropdown__item:hover {
    background: var(--color-bg-hover);
    color: var(--color-text);
}
.nav-dropdown__panel .nav-dropdown__item.active {
    color: var(--color-accent);
}

/* Requirement: auto-populated header dropdowns should resemble the supplied full-width hover bar.
   Approach: keep existing dropdown semantics but render live category/tag/playlist values as compact chips below the sticky header.
   Side effect: the panel is fixed on desktop so it is not clipped by the horizontal nav row. */
.nav-dropdown--header-auto .nav-dropdown__panel {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    width: 100vw;
    min-width: 0;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-md) max(var(--space-md), calc((100vw - var(--container-max)) / 2 + var(--space-md)));
    background: rgba(5, 5, 5, 0.96);
    border-width: 1px 0;
    border-radius: 0;
}
.nav-dropdown--header-auto .nav-dropdown__panel::before {
    top: calc(-1 * var(--space-md));
    height: var(--space-md);
}
.nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item {
    display: inline-flex;
    align-items: center;
    min-height: 30px;
    padding: 5px 14px;
    border: 1px solid var(--color-border);
    background: rgba(0, 0, 0, 0.88);
    color: var(--color-text);
    font-weight: var(--weight-semibold);
    line-height: 1.2;
}
.nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item:hover,
.nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item.active {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: #fff;
}

/* Mobile nav: dropdown panels become inline expandable accordion sections */
.main-nav.is-open .nav-dropdown__panel {
    position: static;
    min-width: 0;
    background: transparent;
    border: none;
    border-radius: 0;
    box-shadow: none;
    padding: 0 0 0 var(--space-md);
    transform: none;
    max-height: 0;
    overflow: hidden;
    opacity: 1;
    transition: max-height var(--transition-base), visibility 0s var(--transition-base);
}
.main-nav.is-open .nav-dropdown__panel::before {
    display: none;
}
.main-nav.is-open .nav-dropdown.is-open .nav-dropdown__panel {
    visibility: visible;
    max-height: 500px;
    transition: max-height var(--transition-base), visibility 0s;
}
.main-nav.is-open .nav-dropdown__panel .nav-dropdown__item {
    white-space: normal;
    padding: var(--space-xs) 0;
}
.main-nav.is-open .nav-dropdown--header-auto .nav-dropdown__panel {
    width: auto;
    display: block;
}
.main-nav.is-open .nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item {
    min-height: 0;
    border: 0;
    background: transparent;
    color: var(--color-text-secondary);
    font-weight: var(--weight-medium);
}
.main-nav.is-open .nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item:hover,
.main-nav.is-open .nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item.active {
    background: transparent;
    color: var(--color-accent);
}

/* Mobile menu toggle button */
.menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: none;
    border: none;
    color: var(--color-text);
    cursor: pointer;
    font-size: var(--font-size-xl);
}

/* Header right section: search + user nav */
.header-actions {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: var(--space-sm);
    min-width: 0;
    flex-shrink: 0;
}

/* Requirement: show membership CTA next to user controls on desktop only to keep phone/tablet headers compact.
   Logic: include the action container so the later generic `.btn` component rule cannot override this visibility contract. */
.header-actions .header-pricing-cta {
    display: none;
}

/* === Video Grid === */
/* Requirement: phone post-list pages should show two columns while still avoiding horizontal overflow.
   Approach: make the shared listing grid two columns by default and use minmax(0, 1fr) so long card content cannot widen the viewport.
   Side effect: homepage/latest, archive/search, and related grids all become denser on phones because they share .video-grid. */
.video-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-md);
}

/* === Page Header (category/tag/search titles) === */
.page-header {
    margin-bottom: var(--space-xl);
}
.page-header__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    line-height: var(--line-height-tight);
}
.page-header__desc {
    color: var(--color-text-secondary);
    margin-top: var(--space-sm);
}

/* === Section Layout === */
/* Requirement: public sections should follow the YiseKan Design System title rhythm.
   Approach: use a compact 42px accent rule instead of a full text-width underline. */
.section {
    margin-bottom: var(--space-2xl);
}
.section__title {
    position: relative;
    font-size: var(--font-size-xl);
    font-weight: var(--weight-bold);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-sm);
    border-bottom: 0;
    display: inline-block;
}
.section__title::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 42px;
    height: 3px;
    background: var(--accent);
    border-radius: 2px;
}

/* === Archive/Search Main + Sidebar Layout === */
/* Requirement: archive/search pages should keep mobile stacking and switch to two columns only when a sidebar renders.
   Approach: define a shared grid wrapper that both archive.php and search.php can reuse.
   Assumption: only archive/search templates mount this wrapper, so other pages keep existing layout.
   Side effect: sidebar-hidden pages no longer reserve an empty desktop column. */
.archive-with-sidebar {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-xl);
    align-items: start;
}

.archive-with-sidebar__main,
.archive-with-sidebar__side {
    min-width: 0;
}

/* === Footer Layout === */
.footer-inner {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-xl);
    margin-bottom: var(--space-xl);
}
.footer-bottom {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    text-align: center;
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

/* ============================================
 * Responsive Breakpoints (mobile-first)
 * sm: 640px, md: 768px, lg: 1024px, xl: 1280px
 * ============================================ */

/* Tablet: 640px+ */
@media (min-width: 640px) {
    .video-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: var(--space-lg);
    }
    .footer-inner {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
        text-align: left;
    }
}

/* Requirement: preserve the two-column phone layout even on very narrow devices.
   Approach: reduce only the inter-card gap below 380px; card internals are compacted in components.css. */
@media (max-width: 380px) {
    .video-grid {
        gap: var(--space-sm);
    }
}

/* Requirement: mobile header should avoid overflow when logo text + search/user actions compete for width.
   Approach: tighten logo width and spacing on narrow screens while preserving existing controls. */
@media (max-width: 640px) {
    .header-inner {
        gap: var(--space-sm);
    }

    .site-logo {
        font-size: var(--font-size-lg);
        max-width: 45vw;
    }

    .header-actions {
        gap: var(--space-xs);
    }
}

/* Tablet landscape: 768px+ */
@media (min-width: 768px) {
    .container {
        padding: 0 var(--space-xl);
    }
    .site-main {
        padding: var(--space-2xl) 0;
    }
}

/* Requirement: tablets need direct header navigation instead of a phone-style hamburger.
   Approach: keep the 64px brand/search row and add a 48px, touch-sized horizontal navigation rail below it.
   Side effect: long admin-configured menus scroll horizontally, while dropdowns open as full-width bounded panels. */
@media (min-width: 768px) and (max-width: 1199px) {
    .site-header {
        height: calc(var(--header-height) + 48px);
    }

    .header-inner {
        height: var(--header-height);
        gap: var(--space-sm);
    }

    .site-logo {
        flex: 1 1 180px;
        max-width: clamp(140px, 24vw, 220px);
    }

    .menu-toggle {
        display: none;
    }

    .main-nav,
    .main-nav.is-open {
        display: flex;
        position: absolute;
        top: var(--header-height);
        left: 0;
        right: 0;
        height: 48px;
        max-height: none;
        flex-direction: row;
        align-items: stretch;
        gap: 4px;
        padding: 0 max(var(--space-md), env(safe-area-inset-left));
        overflow-x: auto;
        overflow-y: hidden;
        overscroll-behavior-x: contain;
        scrollbar-width: thin;
        background: var(--color-bg-elevated);
        border-top: 1px solid var(--color-border);
        border-bottom: 1px solid var(--color-border);
        z-index: var(--z-dropdown);
    }

    .main-nav > a,
    .main-nav > .menu-item,
    .main-nav > .nav-dropdown {
        flex: 0 0 auto;
    }

    .main-nav > .menu-item {
        display: flex;
        align-items: stretch;
        margin: 0;
        list-style: none;
    }

    .main-nav > a,
    .main-nav > .menu-item > a,
    .main-nav > .nav-dropdown > .nav-dropdown__trigger {
        display: inline-flex;
        align-items: center;
        min-height: 44px;
        padding: 0 14px;
        white-space: nowrap;
        border-bottom: 2px solid transparent;
    }

    .main-nav > a:hover,
    .main-nav > a.active,
    .main-nav > .menu-item > a:hover,
    .main-nav > .menu-item > a[aria-current="page"],
    .main-nav > .nav-dropdown > .nav-dropdown__trigger:hover,
    .main-nav > .nav-dropdown > .nav-dropdown__trigger.active {
        border-bottom-color: var(--color-accent);
    }

    /* Requirement: tablet dropdowns must remain usable even when the top-level rail overflows.
       Approach: fixed full-width panels escape horizontal clipping and keep every child within the viewport. */
    .main-nav .nav-dropdown__panel {
        position: fixed;
        top: calc(var(--header-height) + 48px);
        left: 0;
        right: 0;
        width: auto;
        min-width: 0;
        max-height: calc(100svh - var(--header-height) - 48px);
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(148px, 220px));
        justify-content: center;
        gap: var(--space-xs);
        padding: var(--space-md) max(var(--space-md), env(safe-area-inset-left));
        overflow-y: auto;
        overscroll-behavior: contain;
        background: rgba(5, 5, 5, 0.98);
        border-width: 1px 0;
        border-radius: 0;
    }

    .main-nav .nav-dropdown__panel::before {
        display: none;
    }

    .main-nav .nav-dropdown__panel .nav-dropdown__item,
    .main-nav .nav-dropdown--header-auto .nav-dropdown__panel .nav-dropdown__item {
        display: flex;
        align-items: center;
        justify-content: center;
        min-height: 44px;
        padding: var(--space-sm) var(--space-md);
        white-space: normal;
        text-align: center;
        border: 1px solid var(--color-border);
        background: rgba(0, 0, 0, 0.88);
        color: var(--color-text);
        font-weight: var(--weight-semibold);
    }

    .header-actions {
        flex: 0 1 auto;
        max-width: min(52vw, 360px);
    }
}

/* Content desktop: 1024px+ */
@media (min-width: 1024px) {
    .video-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .footer-inner {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1200px) {
    /* Requirement: the complete horizontal header is a desktop-only layout.
       Approach: keep the original single-row presentation at 1200px while tablet uses its dedicated navigation rail. */
    .main-nav,
    .main-nav.is-open {
        display: flex;
        flex-direction: row;
        position: static;
        align-items: center;
        gap: var(--space-lg);
        min-width: 0;
        max-height: none;
        overflow-x: auto;
        overflow-y: visible;
        padding: 0;
        border-bottom: 0;
        background: transparent;
        scrollbar-width: thin;
    }
    .menu-toggle {
        display: none;
    }
    .header-actions .header-pricing-cta {
        display: inline-flex;
    }
    .site-logo {
        flex: 0 1 auto;
        max-width: none;
    }

    .archive-with-sidebar:not(.archive-with-sidebar--no-sidebar) {
        grid-template-columns: minmax(0, 1fr) minmax(260px, 320px);
    }

    .archive-with-sidebar:not(.archive-with-sidebar--no-sidebar) .archive-with-sidebar__side {
        position: sticky;
        top: calc(var(--header-height) + var(--space-lg));
    }
}

/* Large desktop: 1280px+ */
@media (min-width: 1280px) {
    .video-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

/* === Utility Classes === */
.sr-only {
    /* Screen reader only - visually hidden but accessible */
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.text-center { text-align: center; }
.text-muted  { color: var(--color-text-secondary); }
.mt-sm  { margin-top: var(--space-sm); }
.mt-md  { margin-top: var(--space-md); }
.mt-lg  { margin-top: var(--space-lg); }
.mt-xl  { margin-top: var(--space-xl); }
.mb-md  { margin-bottom: var(--space-md); }
.mb-lg  { margin-bottom: var(--space-lg); }
.mb-xl  { margin-bottom: var(--space-xl); }

/* Requirement: support notched/island devices (iPhone X+) in fullscreen/PWA mode.
   Approach: pad header and footer with safe-area-insets so content avoids the notch/home indicator.
   Side effect: only activates when viewport-fit=cover is set in the viewport meta tag. */
@supports (padding: env(safe-area-inset-top)) {
    .site-header {
        padding-left: max(var(--space-md), env(safe-area-inset-left));
        padding-right: max(var(--space-md), env(safe-area-inset-right));
    }
    .site-footer {
        padding-bottom: max(var(--space-lg), env(safe-area-inset-bottom));
    }
}

/* Requirement: print output should omit navigation, player, modals, and interactive elements.
   Approach: hide non-content elements and adjust background/colors for printing. */
@media print {
    .site-header,
    .site-footer,
    .player-wrapper,
    .modal-overlay,
    .toast,
    .menu-toggle,
    .user-nav,
    .header-pricing-cta,
    .pagination {
        display: none !important;
    }

    body {
        background: #fff;
        color: #000;
    }

    .site-main {
        min-height: auto;
    }

    a {
        color: #000;
        text-decoration: underline;
    }
}