/**
 * Card Carousel Component - Modern Campus CMS
 * Pure CSS scroll-snap carousel (no JavaScript library required)
 *
 * Performance Optimized for Lighthouse LCP/CLS:
 * - Native scroll-snap (no JS library)
 * - CSS containment for rendering performance
 * - content-visibility for off-screen optimization
 * - Explicit dimensions to prevent layout shifts
 *
 * Version: 1.1.0
 * Breakpoints: Mobile (<768px), Tablet (768-1023px), Desktop (1024px+)
 */

/* ============================================
   CSS Custom Properties - Theme System
   ============================================ */

:root {
    /* Default Theme (Blue) */
    --card-carousel-bg: #2a2a86;
    --card-carousel-color: #ffffff;
    --card-carousel-card-bg: #080A39;
    --card-carousel-card-overlay: rgba(42, 42, 134, 0.5);
    --card-carousel-cta-bg: #ffe14f;
    --card-carousel-cta-color: #000000;
    --card-carousel-cta-hover-bg: #ffffff;
    --card-carousel-cta-hover-color: #000000;
    --card-carousel-btn-bg: #ffe14f;
    --card-carousel-btn-color: #000000;
    --card-carousel-btn-hover-bg: #ffffff;
    --card-carousel-link-hover: #ffe14f;
    --card-carousel-arrow-bg: #ffe14f;
    --card-carousel-arrow-color: #000000;

    /* Layout */
    --card-carousel-padding-mobile: 20px;
    --card-carousel-padding-tablet: 30px;
    --card-carousel-padding-desktop: 30px 50px;
    --card-carousel-header-mb: 28px;
    --card-carousel-header-mb-tablet: 39px;
    --card-carousel-card-height-tablet: 450px;
    --card-carousel-card-height-desktop: 450px;

    /* Typography */
    --card-carousel-font-family: 'Montserrat', Arial, Helvetica, sans-serif;
    --card-carousel-header-size-mobile: 1.5rem;
    --card-carousel-header-size-desktop: 40px;
    --card-carousel-header-weight: 700;
    --card-carousel-card-header-size-mobile: 18px;
    --card-carousel-card-header-size-tablet: 20px;
    --card-carousel-card-header-size-desktop: 24px;
    --card-carousel-card-header-weight: 800;
    --card-carousel-body-size-mobile: 1rem;
    --card-carousel-body-size-desktop: 18px;
    --card-carousel-body-weight: 500;

    /* Transitions */
    --card-carousel-transition-fast: 0.2s ease;
    --card-carousel-transition-normal: 0.3s ease;

    /* Button sizing */
    --card-carousel-btn-size-mobile: 30px;
    --card-carousel-btn-size-tablet: 42px;
}

/* ============================================
   Theme Variations
   ============================================ */

/* HCCC Primary Theme (Teal) */
.card-carousel--hccc-primary {
    --card-carousel-bg: #006366;
    --card-carousel-card-bg: #00393D;
    --card-carousel-card-overlay: rgba(0, 99, 102, 0.5);
}

/* HCCC Secondary Theme (Blue) - same as default */
.card-carousel--hccc-secondary {
    --card-carousel-bg: #2a2a86;
    --card-carousel-card-bg: #080A39;
    --card-carousel-card-overlay: rgba(42, 42, 134, 0.5);
}

/* Light Theme */
.card-carousel--light {
    --card-carousel-bg: #f5f5f5;
    --card-carousel-color: #000000;
    --card-carousel-card-bg: #ffffff;
    --card-carousel-card-overlay: rgba(255, 255, 255, 0.6);
    --card-carousel-cta-bg: #006366;
    --card-carousel-cta-color: #ffffff;
    --card-carousel-cta-hover-bg: #2a2a86;
    --card-carousel-cta-hover-color: #ffffff;
    --card-carousel-btn-bg: #006366;
    --card-carousel-btn-color: #ffffff;
    --card-carousel-btn-hover-bg: #2a2a86;
    --card-carousel-link-hover: #006366;
    --card-carousel-arrow-bg: #006366;
    --card-carousel-arrow-color: #ffffff;
}

/* Dark Theme */
.card-carousel--dark {
    --card-carousel-bg: #1a1a1a;
    --card-carousel-color: #ffffff;
    --card-carousel-card-bg: #2d2d2d;
    --card-carousel-card-overlay: rgba(26, 26, 26, 0.5);
}

/* White Theme */
.card-carousel--white {
    --card-carousel-bg: #ffffff;
    --card-carousel-color: #000000;
    --card-carousel-card-bg: #f8f8f8;
    --card-carousel-card-overlay: rgba(255, 255, 255, 0.7);
    --card-carousel-cta-bg: #2a2a86;
    --card-carousel-cta-color: #ffffff;
    --card-carousel-cta-hover-bg: #006366;
    --card-carousel-cta-hover-color: #ffffff;
    --card-carousel-btn-bg: #2a2a86;
    --card-carousel-btn-color: #ffffff;
    --card-carousel-btn-hover-bg: #006366;
    --card-carousel-link-hover: #2a2a86;
    --card-carousel-arrow-bg: #2a2a86;
    --card-carousel-arrow-color: #ffffff;
}

/* ============================================
   Section Container (Full-bleed background)
   Uses institutional negative margins for Modern Campus CMS
   ============================================ */

.card-carousel {
    position: relative;
    padding: var(--card-carousel-padding-mobile);
    /* Mobile full-bleed: matches CMS container */
    margin: 3px -35px 0 -15px;
    background: var(--card-carousel-bg);
    color: var(--card-carousel-color);
    overflow: hidden;
    contain: layout style;
}

@media (min-width: 768px) {
    .card-carousel {
        padding: var(--card-carousel-padding-tablet);
        /* Tablet full-bleed */
        margin: -11px -15px 0 -15px;
    }
}

@media (min-width: 1024px) {
    .card-carousel {
        padding: var(--card-carousel-padding-desktop);
        /* Desktop full-bleed: asymmetric to match CMS container */
        margin: 0 -55px 0 -52px;
    }
}

.card-carousel__inner {
    position: relative;
    max-width: 1900px;
    margin: 0 auto;
}

/* ============================================
   Header Section
   ============================================ */

.card-carousel__top {
    margin: 0 0 var(--card-carousel-header-mb);
    /* Padding to indent header from full-bleed edges */
    /* Matches negative margins: mobile -15px left, -35px right */
    padding: 0 35px 0 15px;
}

@media (min-width: 768px) {
    .card-carousel__top {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 20px;
        margin: 0 0 var(--card-carousel-header-mb-tablet);
        /* Matches negative margins: tablet -15px both sides */
        padding: 0 15px;
    }
}

@media (min-width: 1024px) {
    .card-carousel__top {
        /* Matches negative margins: desktop -52px left, -55px right */
        padding: 0 55px 0 52px;
    }
}

.card-carousel__top-content {
    flex: 1 1 0;
    min-width: 0;
}

.card-carousel__header {
    font-family: var(--card-carousel-font-family);
    font-size: var(--card-carousel-header-size-mobile);
    font-weight: var(--card-carousel-header-weight);
    color: inherit;
    margin: 10px 0 0;
    line-height: 1.2;
}

@media (min-width: 768px) {
    .card-carousel__header {
        margin: 0;
    }
}

@media (min-width: 1024px) {
    .card-carousel__header {
        font-size: var(--card-carousel-header-size-desktop);
    }
}

.card-carousel__intro {
    font-size: 16px;
    color: inherit;
    margin: 10px 0 18px;
    line-height: 1.5;
}

@media (min-width: 768px) {
    .card-carousel__intro {
        font-size: 18px;
        margin: 9px 0 0;
    }
}

@media (min-width: 1024px) {
    .card-carousel__intro {
        margin: 21px 0 0;
    }
}

/* CTA Button */
.card-carousel__cta {
    display: inline-block;
    padding: 9px 23px;
    background: var(--card-carousel-cta-bg);
    color: var(--card-carousel-cta-color);
    font-family: var(--card-carousel-font-family);
    font-size: 0.875rem;
    font-weight: 700;
    text-decoration: none;
    border-radius: 999px;
    transition: background-color var(--card-carousel-transition-normal),
                color var(--card-carousel-transition-normal);
    line-height: 1.2;
}

@media (min-width: 768px) {
    .card-carousel__cta {
        font-size: 1rem;
        flex-shrink: 0;
    }
}

@media (min-width: 1024px) {
    .card-carousel__cta {
        padding: 13px 34px;
    }
}

.card-carousel__cta:hover,
.card-carousel__cta:focus {
    background: var(--card-carousel-cta-hover-bg);
    color: var(--card-carousel-cta-hover-color);
}

.card-carousel__cta:focus {
    outline: 2px solid currentColor;
    outline-offset: 2px;
}

/* ============================================
   Cards Track (CSS Scroll-Snap)
   ============================================ */

.card-carousel__slides {
    display: flex;
    gap: 0;
    overflow-x: auto;
    overflow-y: hidden;
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding: 10px 0;
    /* Pull slides to container edges */
    margin: 0 -20px;
    overscroll-behavior-x: contain;
}

@media (min-width: 768px) {
    .card-carousel__slides {
        margin: 0 -30px;
    }
}

@media (min-width: 1024px) {
    .card-carousel__slides {
        /* Match desktop padding for edge-to-edge slides */
        margin: 0 -50px;
    }
}

.card-carousel__slides::-webkit-scrollbar {
    display: none;
}

/* ============================================
   Individual Card
   ============================================ */

.card-carousel__card {
    position: relative;
    flex: 0 0 90%;
    scroll-snap-align: start;
    scroll-snap-stop: always;
    background: var(--card-carousel-card-bg);
    border-radius: 0;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    contain: layout style paint;
}

@media (max-width: 767px) {
    .card-carousel__card:last-of-type {
        flex: 0 0 100%;
    }
}

/* Dimming overlay for non-active cards */
.card-carousel__card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--card-carousel-card-overlay);
    opacity: 1;
    transition: opacity var(--card-carousel-transition-normal);
    pointer-events: none;
    z-index: 6;
}

/* Active card (in viewport) - remove dimming */
.card-carousel__card.is-active::before,
.card-carousel__card:focus-within::before {
    opacity: 0;
}

/* Tablet+ layout */
@media (min-width: 768px) {
    .card-carousel__card {
        flex: 0 0 85%;
        height: var(--card-carousel-card-height-tablet);
        min-height: 0;
        background: transparent;
    }

    .card-carousel__card:last-of-type {
        flex: 0 0 100%;
    }

    /* Gradient overlay for text readability */
    .card-carousel__card::after {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(180deg, rgba(0, 0, 0, 0) 50%, rgba(0, 0, 0, 0.9) 100%);
        z-index: 1;
        pointer-events: none;
    }
}

/* Desktop layout */
@media (min-width: 1024px) {
    .card-carousel__card {
        flex: 0 0 45%;
        max-width: 706px;
        height: var(--card-carousel-card-height-desktop);
    }

    .card-carousel__card:last-of-type,
    .card-carousel__card:nth-last-child(2) {
        flex: 0 0 48%;
        max-width: 762px;
    }
}

/* Off-screen optimization */
@media (min-width: 768px) {
    .card-carousel__card:nth-child(n+4) {
        content-visibility: auto;
        contain-intrinsic-size: 0 var(--card-carousel-card-height-tablet);
    }
}

@media (min-width: 1024px) {
    .card-carousel__card:nth-child(n+4) {
        contain-intrinsic-size: 0 var(--card-carousel-card-height-desktop);
    }
}

/* ============================================
   Card Image
   ============================================ */

.card-carousel__card-img {
    position: relative;
    width: 100%;
    aspect-ratio: 5 / 3;
    overflow: hidden;
    background: var(--card-carousel-card-bg);
    margin-bottom: 20px;
    contain: strict;
}

@supports not (aspect-ratio: 5 / 3) {
    .card-carousel__card-img {
        padding-bottom: 60%;
        height: 0;
    }
}

.card-carousel__card-img img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--card-carousel-transition-normal);
    background-color: var(--card-carousel-card-bg);
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .card-carousel__card:hover .card-carousel__card-img img {
        transform: scale(1.05);
    }
}

@media (min-width: 768px) {
    .card-carousel__card-img {
        position: absolute;
        inset: 0;
        aspect-ratio: auto;
        margin: 0;
        z-index: 0;
    }

    @supports not (aspect-ratio: 5 / 3) {
        .card-carousel__card-img {
            padding-bottom: 0;
            height: 100%;
        }
    }
}

/* ============================================
   Card Content
   ============================================ */

.card-carousel__card-content {
    padding: 0 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

@media (min-width: 768px) {
    .card-carousel__card-content {
        position: absolute;
        bottom: 0;
        left: 0;
        right: 0;
        z-index: 2;
        padding: 0 60px 38px 20px;
    }
}

@media (min-width: 1024px) {
    .card-carousel__card-content {
        padding: 0 30px 38px 30px;
    }
}

.card-carousel__card-header {
    font-family: var(--card-carousel-font-family);
    font-size: var(--card-carousel-card-header-size-mobile);
    font-weight: var(--card-carousel-card-header-weight);
    color: inherit;
    margin: 0 0 2px;
    line-height: 1.3;
    letter-spacing: 0.3px;
}

@media (min-width: 768px) {
    .card-carousel__card-header {
        font-size: var(--card-carousel-card-header-size-tablet);
    }
}

@media (min-width: 1024px) {
    .card-carousel__card-header {
        font-size: var(--card-carousel-card-header-size-desktop);
    }
}

.card-carousel__card-header a {
    color: inherit;
    text-decoration: none;
    display: inline-flex;
    align-items: baseline;
    gap: 8px;
    transition: color var(--card-carousel-transition-fast);
}

.card-carousel__card-header a:hover,
.card-carousel__card-header a:focus {
    color: var(--card-carousel-link-hover);
}

.card-carousel__card-header a:focus {
    outline: 2px solid currentColor;
    outline-offset: 2px;
}

/* Arrow decoration */
.card-carousel__card-arrow {
    display: inline-block;
    position: relative;
    width: 16px;
    height: 16px;
    background-color: var(--card-carousel-arrow-bg);
    border-radius: 100%;
    vertical-align: middle;
    margin-left: 6px;
    flex-shrink: 0;
    transition: transform var(--card-carousel-transition-normal);
}

.card-carousel__card-arrow::before {
    content: '';
    position: absolute;
    top: 50%;
    right: calc(50% - 2px);
    width: 4px;
    height: 4px;
    border-top: 2px solid var(--card-carousel-arrow-color);
    border-right: 2px solid var(--card-carousel-arrow-color);
    transform: translateY(-50%) rotate(45deg);
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .card-carousel__card-header a:hover .card-carousel__card-arrow,
    .card-carousel__card-header a:focus .card-carousel__card-arrow {
        transform: translateX(4px);
    }
}

@media (min-width: 768px) {
    .card-carousel__card-arrow {
        width: 20px;
        height: 20px;
    }

    .card-carousel__card-arrow::before {
        width: 5px;
        height: 5px;
        right: calc(50% - 3px);
    }
}

.card-carousel__card-body {
    font-size: var(--card-carousel-body-size-mobile);
    font-weight: var(--card-carousel-body-weight);
    color: inherit;
    margin: 0;
    line-height: 1.5;
    flex: 1;
}

@media (min-width: 1024px) {
    .card-carousel__card-body {
        font-size: var(--card-carousel-body-size-desktop);
    }
}

/* ============================================
   Navigation Buttons
   ============================================ */

.card-carousel__btn {
    position: absolute;
    top: 31%;
    transform: translateY(-50%);
    width: var(--card-carousel-btn-size-mobile);
    height: var(--card-carousel-btn-size-mobile);
    padding: 0;
    background: var(--card-carousel-btn-bg);
    border: none;
    border-radius: 100%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
    opacity: 1;
    transition: opacity var(--card-carousel-transition-normal),
                background-color var(--card-carousel-transition-normal);
}

@media (min-width: 768px) {
    .card-carousel__btn {
        top: 49%;
        width: var(--card-carousel-btn-size-tablet);
        height: var(--card-carousel-btn-size-tablet);
    }
}

.card-carousel__btn:hover:not(:disabled) {
    background: var(--card-carousel-btn-hover-bg);
}

.card-carousel__btn:focus {
    outline: 2px solid var(--card-carousel-color);
    outline-offset: 2px;
}

.card-carousel__btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.card-carousel__btn--prev {
    left: 8px;
}

.card-carousel__btn--next {
    right: 8px;
}

@media (min-width: 768px) {
    .card-carousel__btn--prev { left: 25px; }
    .card-carousel__btn--next { right: 25px; }
}

@media (min-width: 1024px) {
    .card-carousel__btn--prev { left: 48px; }
    .card-carousel__btn--next { right: 48px; }
}

/* CSS Arrow Icons */
.card-carousel__btn::after {
    content: '';
    position: absolute;
    left: calc(50% - 2px);
    top: 50%;
    width: 0.55rem;
    height: 0.55rem;
    background: none;
    border-top: 2px solid var(--card-carousel-btn-color);
    border-right: 2px solid var(--card-carousel-btn-color);
    transform: translate(-50%, -50%) rotate(45deg);
}

.card-carousel__btn--prev::after {
    left: calc(50% + 2px);
    transform: translate(-50%, -50%) rotate(-135deg);
}

/* ============================================
   Accessibility
   ============================================ */

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

@media (prefers-reduced-motion: reduce) {
    .card-carousel__slides {
        scroll-behavior: auto;
    }

    .card-carousel__card-img img,
    .card-carousel__card-arrow,
    .card-carousel__cta,
    .card-carousel__btn,
    .card-carousel__card::before {
        transition: none;
    }
}

@media (prefers-contrast: high) {
    .card-carousel__card {
        border: 2px solid currentColor;
    }

    .card-carousel__cta,
    .card-carousel__btn {
        border: 2px solid currentColor;
    }
}

.card-carousel__card-header a:focus-visible,
.card-carousel__cta:focus-visible,
.card-carousel__btn:focus-visible {
    outline: 3px solid currentColor;
    outline-offset: 3px;
}

.card-carousel__card-header a:focus:not(:focus-visible),
.card-carousel__cta:focus:not(:focus-visible),
.card-carousel__btn:focus:not(:focus-visible) {
    outline: none;
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
    .card-carousel {
        background: none;
        color: #000;
        margin: 0;
        padding: 20px 0;
    }

    .card-carousel__slides {
        display: block;
        overflow: visible;
    }

    .card-carousel__card {
        display: block;
        margin-bottom: 20px;
        page-break-inside: avoid;
    }

    .card-carousel__btn {
        display: none;
    }

    .card-carousel__card::before,
    .card-carousel__card::after {
        display: none;
    }
}