/*
 * courses.css  — Course listing page styles
 * Mobile-first responsive design
 */

/* ─── CSS Variables ─── */
:root {
    --teal-deep:    #5fb3b3;
    --mint-medium:  #88c999;
    --mint-light:   #b8e6c1;
    --cream-yellow: #f0e6a6;
    --text-dark:    #1f2937;
    --text-medium:  #6b7280;
    --text-light:   #9ca3af;
}

/* ─── Page Hero Banner ─── */
.courses-hero {
    background: linear-gradient(135deg, #1a5f5f 0%, #2d8989 40%, #5fb3b3 75%, #7ec99a 100%);
    padding: 20px 0 44px;
    color: #fff;
    position: relative;
    overflow: hidden;
}

.courses-hero::before {
    content: '';
    position: absolute;
    top: -50px; right: -50px;
    width: 180px; height: 180px;
    background: rgba(255,255,255,0.06);
    border-radius: 50%;
    pointer-events: none;
}

.courses-hero::after {
    content: '';
    position: absolute;
    bottom: -30px; left: -20px;
    width: 120px; height: 120px;
    background: rgba(255,255,255,0.04);
    border-radius: 50%;
    pointer-events: none;
}

.courses-hero-title {
    font-size: clamp(1.4rem, 5vw, 2rem);
    font-weight: 700;
    margin-bottom: 6px;
    color: #fff;
    position: relative;
}

.courses-hero-sub {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.85);
    margin-bottom: 0;
    position: relative;
}

.courses-breadcrumb {
    margin-bottom: 10px;
    position: relative;
}

@media (min-width: 576px) {
    .courses-hero { padding: 28px 0 52px; }
}

/* ─── Main container (overlaps hero) ─── */
.courses-main {
    margin-top: -24px;
    position: relative;
    z-index: 10;
    padding-bottom: 3rem;
}

/* ─── Filter Card ─── */
.courses-filter {
    padding: 16px !important;
    margin-bottom: 16px !important;
}

/* Search row */
.filter-search-row {
    display: flex;
    align-items: center;
    gap: 10px;
}

.filter-search-wrap {
    position: relative;
    flex: 1;
    min-width: 0;
}

.filter-search-icon {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: #adb5bd;
    font-size: 0.9rem;
    pointer-events: none;
}

.filter-search-input {
    width: 100%;
    padding: 9px 36px 9px 36px;
    border: 1.5px solid #e5e7eb;
    border-radius: 50px;
    font-size: 0.875rem;
    background: #f8f9fa;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.filter-search-input:focus {
    border-color: var(--teal-deep);
    box-shadow: 0 0 0 3px rgba(95,179,179,0.15);
    background: #fff;
}

.filter-search-clear {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: #ced4da;
    text-decoration: none;
    font-size: 0.85rem;
    line-height: 1;
    transition: color 0.2s;
}

.filter-search-clear:hover { color: #868e96; }

/* Mobile filter toggle button */
.filter-toggle-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 8px 14px;
    border: 1.5px solid #dee2e6;
    border-radius: 50px;
    background: #fff;
    font-size: 0.84rem;
    font-weight: 500;
    color: #495057;
    cursor: pointer;
    white-space: nowrap;
    position: relative;
    transition: border-color 0.2s, color 0.2s;
    flex-shrink: 0;
}

.filter-toggle-btn:hover,
.filter-toggle-btn[aria-expanded="true"] {
    border-color: var(--teal-deep);
    color: var(--teal-deep);
}

/* Orange dot when filters are active */
.filter-active-dot {
    width: 7px;
    height: 7px;
    background: #f59e0b;
    border-radius: 50%;
    position: absolute;
    top: 5px;
    right: 5px;
}

/* Dropdown filter rows */
.filter-dropdowns {
    padding-top: 12px;
    margin-top: 4px;
    border-top: 1px solid #f3f4f6;
}

.filter-label {
    display: block;
    font-size: 11px;
    font-weight: 600;
    color: #6c757d;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
}

/* ─── Results bar ─── */
.results-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    padding: 0 2px;
}

.results-count {
    font-size: 0.875rem;
    color: #6c757d;
}

.results-count strong {
    color: #1f2937;
    font-weight: 700;
}

/* ─── Background gradient (page-level) ─── */
.bg-gradient {
    background: linear-gradient(135deg,
        var(--teal-deep) 0%,
        var(--mint-medium) 35%,
        var(--mint-light) 70%,
        var(--cream-yellow) 100%
    ) !important;
    color: var(--text-dark) !important;
}

/* ─── Course Cards ─── */
.course-card {
    background: #fff;
    border-radius: 12px;
    border: none;
    border-top: 3px solid var(--mint-medium);
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(95,179,179,0.1);
    transition: transform 0.25s ease, box-shadow 0.25s ease;
    display: flex;
    flex-direction: column;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(95,179,179,0.18);
}

.course-image-container {
    position: relative;
    overflow: hidden;
    background: rgba(184,230,193,0.12);
}

.course-card .card-img-top {
    width: 100%;
    height: 180px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.course-card:hover .card-img-top {
    transform: scale(1.04);
}

.course-card .card-body {
    padding: 16px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

/* ─── Price Overlay ─── */
.price-overlay {
    position: absolute;
    top: 10px;
    right: 10px;
    z-index: 10;
}

.price-overlay .price-badge {
    font-size: 0.78rem;
    padding: 4px 10px;
    border-radius: 50px;
    font-weight: 600;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    backdrop-filter: blur(8px);
}

/* ─── Badges ─── */
.badge-container {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 10px;
}

.course-card .badge {
    font-size: 0.72rem;
    padding: 4px 9px;
    border-radius: 6px;
    font-weight: 500;
}

.badge.bg-primary {
    background: linear-gradient(135deg, var(--teal-deep), var(--mint-medium)) !important;
}

.badge.bg-success {
    background: linear-gradient(135deg, var(--mint-medium), var(--mint-light)) !important;
}

.badge.bg-info {
    background: linear-gradient(135deg, var(--teal-deep), #0369a1) !important;
}

.badge.bg-warning {
    background: linear-gradient(135deg, var(--cream-yellow), #facc15) !important;
    color: #374151 !important;
}

/* ─── Card text ─── */
.course-card .card-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-dark);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-card .card-text.small {
    font-size: 0.8rem;
    color: var(--text-medium);
    margin-bottom: 8px;
}

.course-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    font-size: 0.78rem;
    color: var(--text-medium);
}

/* ─── Card content wrapper (grows to push button down) ─── */
.card-top {
    flex-grow: 1;
}

/* ─── Price section ─── */
.price-section {
    border-top: 1px solid #f3f4f6;
    padding-top: 12px;
}

.price-badge {
    font-weight: 600;
    padding: 5px 12px;
    border-radius: 50px;
    font-size: 0.85rem;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.price-free     { background: linear-gradient(135deg, var(--mint-medium), var(--mint-light)); color: white; }
.price-paid     { background: linear-gradient(135deg, var(--teal-deep), var(--mint-medium)); color: white; }
.price-discount { background: linear-gradient(135deg, #f59e0b, #d97706); color: white; }
.price-early-bird { background: linear-gradient(135deg, #8b5cf6, #7c3aed); color: white; }

.original-price {
    text-decoration: line-through;
    color: var(--text-light);
    font-size: 0.8rem;
}

/* ─── Buttons ─── */
.btn-outline-primary {
    color: var(--teal-deep);
    border-color: var(--teal-deep);
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.875rem;
    padding: 8px 16px;
    transition: all 0.2s ease;
}

.btn-outline-primary:hover {
    background: var(--teal-deep);
    border-color: var(--teal-deep);
    color: white;
    transform: translateY(-1px);
}

/* ─── Form controls ─── */
.form-control, .form-select {
    border-radius: 8px;
    border: 1.5px solid #e5e7eb;
    font-size: 0.875rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control:focus, .form-select:focus {
    border-color: var(--teal-deep);
    box-shadow: 0 0 0 3px rgba(95,179,179,0.15);
}

/* ─── Pagination ─── */
.pagination {
    justify-content: center;
    gap: 4px;
}

.page-link {
    color: var(--teal-deep);
    border-color: #e5e7eb;
    border-radius: 8px !important;
    padding: 6px 12px;
    font-size: 0.875rem;
    transition: all 0.2s ease;
}

.page-link:hover {
    background: var(--teal-deep);
    border-color: var(--teal-deep);
    color: white;
}

.page-item.active .page-link {
    background: var(--teal-deep);
    border-color: var(--teal-deep);
}

.page-item.disabled .page-link {
    color: #ced4da;
}

/* ─── Mobile tweaks (< 576px) — 2-column card grid ─── */
@media (max-width: 575px) {
    .courses-hero { padding: 16px 0 40px; }
    .courses-main { margin-top: -20px; }

    /* Compact cards for 2-column layout */
    .course-card .card-img-top  { height: 110px; }
    .course-card .card-body     { padding: 10px; }
    .course-card .card-title    { font-size: 0.78rem; margin-bottom: 6px; -webkit-line-clamp: 3; }
    .course-card .card-text.small { font-size: 0.72rem; margin-bottom: 6px; }
    .badge-container            { gap: 4px; margin-bottom: 6px; }
    .course-card .badge         { font-size: 0.65rem; padding: 3px 6px; }
    .course-info                { font-size: 0.7rem; margin-bottom: 6px; flex-direction: column; align-items: flex-start; gap: 2px; }
    .price-section              { padding-top: 8px; }
    .price-overlay .price-badge { font-size: 0.68rem; padding: 3px 7px; }
    .btn-outline-primary        { font-size: 0.75rem; padding: 6px 8px; }

    .filter-search-input { font-size: 0.82rem; }
    .results-bar { flex-direction: column; align-items: flex-start; gap: 8px; }
}

/* ─── Tablet (577–991px) ─── */
@media (min-width: 577px) and (max-width: 991px) {
    .course-card .card-img-top { height: 200px; }
}

/* ─── Desktop (≥992px) ─── */
@media (min-width: 992px) {
    .courses-filter { padding: 20px !important; }
    .filter-search-input { font-size: 0.9rem; }
    .course-card .card-img-top { height: 190px; }
}

/* ─── 4-column (≥1200px) ─── */
@media (min-width: 1200px) {
    .course-card .card-img-top { height: 160px; }
    .course-card .card-title   { font-size: 0.9rem; }
}

/* ─── Clickable image ─── */
.course-image-link {
    display: block;
    overflow: hidden;
}

.course-image-link:hover .card-img-top {
    transform: scale(1.04);
}

/* ─── Animation ─── */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* ─── KU MOOC index visual system ─── */
body {
    background: #fbfdfc;
    color: #10231d;
    font-family: 'IBM Plex Sans Thai', 'Noto Sans Thai', sans-serif;
}
h1, h2, h3, h4, h5, h6 {
    font-family: Inter, 'IBM Plex Sans Thai', sans-serif;
    letter-spacing: -.015em;
    line-height: 1.35;
}
.courses-hero {
    background: var(--ku-hero-bg);
    padding: 34px 0 68px;
    color: #10231d;
    overflow: hidden;
    isolation: isolate;
}
.courses-hero::before,
.courses-hero::after {
    display: none;
    animation: none;
}
.courses-hero::before {
    content: '';
    position: absolute;
    inset: -30% -8%;
    background: repeating-radial-gradient(ellipse 75% 34% at 77% 2%, transparent 0 13px, rgba(112,185,124,.19) 14px 15px, transparent 16px 23px), repeating-radial-gradient(ellipse 90% 42% at 18% 105%, transparent 0 16px, rgba(148,160,178,.13) 17px 18px, transparent 19px 28px);
    transform: rotate(-7deg) translateX(0);
    animation: courses-wave 18s ease-in-out infinite;
    pointer-events: none;
}
.courses-hero::after {
    content: '';
    position: absolute;
    inset: 0;
    background: repeating-radial-gradient(ellipse 62% 25% at 84% 28%, transparent 0 18px, rgba(6,118,71,.1) 19px 20px, transparent 21px 31px), linear-gradient(125deg, transparent 20%, rgba(255,255,255,.7) 48%, transparent 74%);
    transform: skewY(-5deg) translateX(0);
    animation: courses-wave-secondary 21s ease-in-out infinite;
    pointer-events: none;
}
.courses-hero .container { position: relative; z-index: 1; }
.courses-breadcrumb { animation: courses-fade-up .6s ease both; }
.courses-hero-title { animation: courses-fade-up .7s .08s ease both; }
.courses-hero-sub { animation: courses-fade-up .7s .16s ease both; }
.courses-hero-title { color: #062f25; font-size: clamp(2rem, 5vw, 3rem); letter-spacing: -.025em; }
.courses-hero-sub { color: #62756d; font-size: 1.05rem; }
.courses-main { margin-top: -30px; animation: courses-fade-up .75s .2s ease both; }
.courses-filter, .course-card {
    border: 1px solid #dceae3;
    border-radius: 20px;
    box-shadow: 0 10px 28px rgba(18,85,54,.07);
}
.courses-filter { background: #fff; }
.filter-search-input { border-color: #dceae3; background: #f8fcfa; font-size: .95rem; }
.filter-search-input:focus, .form-control:focus, .form-select:focus { border-color: #067647; box-shadow: 0 0 0 3px rgba(6,118,71,.12); }
.filter-toggle-btn { border-color: #b8ddcc; color: #067647; }
.filter-toggle-btn:hover, .filter-toggle-btn[aria-expanded="true"] { border-color: #067647; color: #067647; background: #edf8f3; }
.course-card { border-top: 0; overflow: hidden; transition: transform .25s ease, box-shadow .25s ease; }
.course-card:hover { transform: translateY(-6px); box-shadow: 0 18px 35px rgba(18,85,54,.14); }
.course-card .card-title { font-family: 'IBM Plex Sans Thai', sans-serif; font-size: 1.05rem; line-height: 1.5; }
.course-card .card-text.small, .course-info { font-size: .9rem; }
.results-bar { color: #62756d; }
.btn-primary, .page-item.active .page-link { background: #067647 !important; border-color: #067647 !important; }
.btn-outline-primary, .page-link { color: #067647; border-color: #067647; }
.btn-outline-primary:hover, .page-link:hover { background: #067647; border-color: #067647; color: #fff; }
.badge.bg-success, .price-free { background: #b8e6c1 !important; color: #1b4332 !important; }
.badge.bg-primary, .price-paid { background: #dff8ec !important; color: #067647 !important; }

@media (max-width: 575px) {
    .courses-hero { padding: 24px 0 52px; }
    .courses-main { margin-top: -22px; }
    .course-card .card-img-top { height: 160px; }
    .course-card .card-body { padding: 16px; }
    .course-card .card-title { font-size: .98rem; }
    .course-card .card-text.small { font-size: .82rem; }
}

@keyframes courses-fade-up {
    from { opacity: 0; transform: translateY(14px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes courses-wave {
    0%, 100% { transform: rotate(-7deg) translate3d(0, 0, 0) scale(1); }
    50% { transform: rotate(-4deg) translate3d(-18px, 10px, 0) scale(1.04); }
}
@keyframes courses-wave-secondary {
    0%, 100% { transform: skewY(-5deg) translate3d(0, 0, 0); }
    50% { transform: skewY(-2deg) translate3d(20px, -8px, 0); }
}
@media (prefers-reduced-motion: reduce) {
    .courses-hero::before, .courses-hero::after, .courses-breadcrumb,
    .courses-hero-title, .courses-hero-sub, .courses-main {
        animation: none;
    }
}

/* Mobile layout: one readable course per row with touch-friendly controls. */
@media (max-width: 575.98px) {
    .courses-hero {
        padding: 22px 0 50px;
    }

    .courses-hero-title {
        font-size: 1.8rem;
    }

    .courses-hero-sub {
        font-size: .92rem;
        line-height: 1.65;
    }

    .courses-main {
        margin-top: -22px;
        padding-right: 12px;
        padding-left: 12px;
    }

    .courses-filter {
        padding: 12px !important;
        border-radius: 16px;
    }

    .filter-search-row {
        display: grid;
        grid-template-columns: minmax(0, 1fr) 96px;
        gap: 10px;
    }

    .filter-search-input,
    .filter-toggle-btn {
        min-height: 44px;
    }

    .filter-search-input {
        display: block;
        font-size: .875rem;
    }

    .filter-toggle-btn {
        width: 96px;
        justify-content: center;
        gap: 6px;
        padding: 8px 10px;
        border-color: #9dcfba;
        font-size: .875rem;
        line-height: 1;
    }

    .filter-toggle-btn .filter-toggle-icon {
        flex: 0 0 auto;
        margin: 0;
        font-size: .95rem;
    }

    .filter-toggle-btn.is-open {
        border-color: #067647;
        background: #067647;
        color: #fff;
    }

    .filter-dropdowns .btn {
        min-height: 44px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        gap: 6px;
        padding: 9px 16px;
        border-radius: 12px;
        font-size: .875rem;
        font-weight: 600;
        line-height: 1.2;
    }

    .filter-dropdowns .btn i {
        margin-right: 0 !important;
        line-height: 1;
    }

    .course-card {
        flex-direction: row;
        align-items: stretch;
        border-radius: 16px;
    }

    .course-image-container {
        flex: 0 0 38%;
        width: 38%;
        min-width: 120px;
    }

    .course-image-link {
        height: 100%;
    }

    .course-card .card-img-top {
        height: 100%;
        min-height: 190px;
        aspect-ratio: auto;
    }

    .course-card .card-body {
        min-width: 0;
        padding: 12px;
    }

    .course-card .card-title {
        margin-bottom: 7px;
        font-size: .95rem;
        display: -webkit-box;
        overflow: hidden;
        text-overflow: ellipsis;
        -webkit-box-orient: vertical;
        -webkit-line-clamp: 2;
        line-clamp: 2;
    }

    .course-card .card-text.small {
        margin-bottom: 7px;
        font-size: .84rem;
    }

    .badge-container {
        gap: 5px;
        margin-bottom: 8px;
    }

    .course-card .badge {
        padding: 3px 6px;
        font-size: .65rem;
    }

    .course-info {
        flex-direction: row;
        align-items: center;
        margin-bottom: 8px;
        font-size: .8rem;
    }

    .price-section {
        padding-top: 10px;
    }

    .price-overlay .price-badge {
        padding: 4px 8px;
        font-size: .72rem;
    }

    .course-card .btn-outline-primary {
        min-height: 44px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        gap: 6px;
        padding: 8px 12px;
        border-width: 1.5px;
        border-radius: 12px;
        font-size: .82rem;
        line-height: 1.2;
        white-space: nowrap;
    }

    .course-card .btn-outline-primary i {
        margin-right: 0 !important;
        font-size: .9rem;
        line-height: 1;
    }
}

@media (max-width: 359.98px) {
    .course-image-container {
        flex-basis: 36%;
        width: 36%;
        min-width: 104px;
    }

    .course-card .card-body {
        padding: 10px;
    }
}