:root {
    --primary: #DC4E28;
    --secondary: #FF8B54;
    --sunny: #FFE0B3;
    --deep-blue: #3C2A1E;
    --soft-bg: #FFF5EE;
}

* {
    box-sizing: border-box;
}

[hidden] {
    display: none !important;
}

.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;
}

body {
    margin: 0;
    font-family: 'Nunito', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--soft-bg);
    color: var(--deep-blue);
}

.container {
    width: min(1200px, 94%);
    margin: 0 auto;
}

.site-header {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 2rem;
    padding: 1.5rem 0;
}

.logo-block {
    display: flex;
    align-items: center;
    gap: 0.9rem;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    font-weight: 600;
    font-size: 0.95rem;
}

.main-nav a {
    color: var(--deep-blue);
    text-decoration: none;
    padding: 0.35rem 0.2rem;
    border-radius: 999px;
    transition: color 0.25s ease, background 0.25s ease;
}

.main-nav a:hover,
.main-nav a:focus {
    color: var(--primary);
    background: #fff0e7;
}

.site-header > .btn-login {
    margin-left: auto;
}

.header-actions {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.header-actions > .btn-login {
    margin-left: 0;
}

.user-menu {
    position: relative;
}

.user-toggle {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    border: none;
    background: var(--deep-blue);
    color: #fff;
    padding: 0.85rem 1.4rem;
    border-radius: 999px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    box-shadow: 0 12px 20px rgba(60, 42, 30, 0.18);
    transition: background 0.25s ease, box-shadow 0.25s ease;
}

.user-toggle:focus-visible {
    outline: 2px solid var(--secondary);
    outline-offset: 2px;
}

.user-greeting {
    opacity: 0.72;
}

.user-name {
    font-weight: 700;
}

.user-caret {
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 6px solid currentColor;
    transition: transform 0.2s ease;
}

.user-menu.is-open .user-caret {
    transform: rotate(180deg);
}

.user-dropdown {
    position: absolute;
    top: calc(100% + 0.75rem);
    right: 0;
    min-width: 180px;
    background: #fff;
    padding: 0.75rem;
    border-radius: 16px;
    box-shadow: 0 18px 40px rgba(60, 42, 30, 0.18);
    display: none;
    z-index: 20;
}

.user-menu.is-open .user-dropdown {
    display: block;
}

.user-action {
    display: block;
    text-decoration: none;
    color: var(--deep-blue);
    font-weight: 600;
    padding: 0.6rem 0.9rem;
    border-radius: 12px;
    background: rgba(60, 42, 30, 0.06);
    transition: background 0.2s ease, color 0.2s ease;
}

.user-action:hover,
.user-action:focus {
    background: var(--deep-blue);
    color: #fff;
}

.user-action:focus-visible {
    outline: 2px solid var(--secondary);
    outline-offset: 2px;
}

.site-logo {
    width: clamp(110px, 13vw, 180px);
    height: auto;
    display: block;
    filter: drop-shadow(0 12px 24px rgba(220, 78, 40, 0.18));
}

.logo-circle {
    width: 64px;
    height: 64px;
    border-radius: 32px;
    background: linear-gradient(135deg, #FF8B54, #FFD3A8);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    border: 3px solid #fff;
    box-shadow: 0 10px 24px rgba(220, 78, 40, 0.25);
}

.brand {
    font-family: 'Baloo 2', cursive;
    font-size: 1.8rem;
    margin: 0;
}

.tagline {
    margin: 0;
    color: #C47A55;
    font-size: 0.95rem;
}

.btn-login {
    border: none;
    background: linear-gradient(145deg, #FF9E6C, var(--secondary));
    color: #fff;
    font-weight: 700;
    padding: 0.9rem 1.6rem;
    border-radius: 999px;
    font-weight: 600;
    box-shadow: 0 14px 28px rgba(255, 139, 84, 0.25);
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
}

.btn-login:hover,
.btn-login:focus {
    text-decoration: none;
    box-shadow: 0 18px 32px rgba(255, 139, 84, 0.3);
}

.btn-login.ghost {
    background: rgba(60, 42, 30, 0.08);
    color: var(--deep-blue);
    box-shadow: none;
}

.hero {
    background: transparent;
    border-radius: 32px;
    padding: 0;
    margin-bottom: 2rem;
}

.slider {
    position: relative;
    width: 100%;
    aspect-ratio: 1920 / 500;
    border-radius: 24px;
    overflow: hidden;
    background: #FFE2D2;
    box-shadow: 0 25px 60px rgba(60, 42, 30, 0.18);
}

.slide {
    position: absolute;
    inset: 0;
    opacity: 0;
    transition: opacity 0.6s ease;
    pointer-events: none;
    display: block;
}

.slide.active {
    opacity: 1;
    pointer-events: auto;
}

.slide img {
    width: 100%;
    height: auto;
    object-fit: cover;
    display: block;
}

.slider-control {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 48px;
    height: 48px;
    border: none;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.9);
    color: var(--deep-blue);
    box-shadow: 0 18px 32px rgba(60, 42, 30, 0.2);
    display: grid;
    place-items: center;
    cursor: pointer;
    transition: background 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
}

.slider-control:hover,
.slider-control:focus {
    background: rgba(255, 139, 84, 0.92);
    color: #fff;
    box-shadow: 0 20px 36px rgba(255, 139, 84, 0.35);
    outline: none;
}

.slider-control:focus-visible {
    box-shadow: 0 0 0 3px rgba(255, 139, 84, 0.4);
}

.slider-control--prev {
    left: 1.25rem;
}

.slider-control--next {
    right: 1.25rem;
}

.slider-control svg {
    width: 22px;
    height: 22px;
}

.slider-dots {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1rem;
}

.slider-dot {
    width: 12px;
    height: 12px;
    border-radius: 6px;
    background: rgba(60, 42, 30, 0.2);
    cursor: pointer;
    transition: all 0.3s;
}

.slider-dot.active {
    width: 32px;
    background: var(--primary);
}

.section-heading {
    margin: 3rem 0 1rem;
    text-align: center;
}

.section-heading h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
}

.course-card {
    border-radius: 32px;
    padding: 1.6rem;
    position: relative;
    box-shadow: 0 25px 50px rgba(60, 42, 30, 0.16);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.pagination {
    margin-top: clamp(1.5rem, 3vw, 2.5rem);
    display: flex;
    justify-content: center;
}

.pagination ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    gap: 0.5rem;
}

.pagination a,
.pagination span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    padding: 0.45rem 0.75rem;
    border-radius: 999px;
    font-weight: 700;
    text-decoration: none;
    color: var(--deep-blue);
    background: rgba(60, 42, 30, 0.08);
    transition: background 0.2s ease, color 0.2s ease;
}

.pagination a:hover,
.pagination a:focus {
    background: var(--deep-blue);
    color: #fff;
}

.pagination span.current {
    background: var(--secondary);
    color: var(--deep-blue);
    cursor: default;
}

.class-section {
    padding: 0;
    margin-bottom: clamp(2.5rem, 5vw, 4rem);
}

.class-section .section-heading {
    margin-top: clamp(2rem, 4vw, 3rem);
}

.home-course-section .course-grid {
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    justify-items: stretch;
    gap: clamp(1.25rem, 2vw, 2rem);
}

.home-course-section .course-card {
    padding: 1.4rem;
    gap: 0.85rem;
    max-width: none;
    margin: 0;
    height: 100%;
    box-shadow: 0 22px 48px rgba(60, 42, 30, 0.16);
}

.home-course-section .course-empty-state {
    text-align: center;
    margin: 2rem auto;
    max-width: 520px;
}

.course-category-tabs {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
    margin: clamp(1.5rem, 3vw, 2.2rem) 0;
}

.course-category-tabs .category-tab {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.6rem 1.4rem;
    border-radius: 999px;
    background: #fff;
    color: var(--deep-blue);
    text-decoration: none;
    font-weight: 600;
    box-shadow: 0 12px 24px rgba(60, 42, 30, 0.12);
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
}

.course-category-tabs .category-tab:hover,
.course-category-tabs .category-tab:focus {
    transform: translateY(-1px);
    box-shadow: 0 16px 30px rgba(60, 42, 30, 0.16);
}

.course-category-tabs .category-tab:focus-visible {
    outline: 2px solid var(--secondary);
    outline-offset: 2px;
}

.course-category-tabs .category-tab.is-active {
    background: linear-gradient(145deg, #FF9E6C, var(--secondary));
    color: #fff;
    box-shadow: 0 20px 36px rgba(255, 139, 84, 0.35);
}

.course-category-tabs .category-tab.is-active .category-count {
    background: rgba(255, 255, 255, 0.55);
    color: var(--deep-blue);
}

.course-category-tabs .category-count {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 1.8rem;
    height: 1.8rem;
    padding: 0 0.5rem;
    border-radius: 999px;
    background: rgba(60, 42, 30, 0.08);
    font-size: 0.8rem;
    font-weight: 700;
}

.class-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    justify-content: center;
    gap: clamp(1.5rem, 3vw, 2.2rem);
}

.class-card {
    border-radius: 32px;
    padding: 1.6rem;
    box-shadow: 0 25px 50px rgba(60, 42, 30, 0.16);
    display: flex;
    flex-wrap: wrap;
    gap: 1.25rem;
    min-height: 100%;
    color: var(--deep-blue);
    position: relative;
}

.class-card.restricted {
    border: 2px dashed rgba(60, 42, 30, 0.12);
}

.class-card-content {
    flex: 1 1 280px;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    min-width: 0;
}

.class-cover {
    width: 100%;
    aspect-ratio: 16 / 9;
    border-radius: 24px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.45);
}

.class-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.class-body {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.class-body h3 {
    margin: 0;
    font-size: 1.2rem;
    font-family: 'Baloo 2', cursive;
}

.class-meta {
    margin: 0;
    color: #B96947;
    font-weight: 600;
    font-size: 0.9rem;
}

.class-courses-wrapper {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.class-courses-heading {
    margin: 0;
    font-weight: 700;
    font-size: 0.95rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: rgba(60, 42, 30, 0.7);
}

.class-courses {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.class-courses li a {
    display: inline-flex;
    padding: 0.35rem 0.75rem;
    border-radius: 999px;
    background: rgba(255, 139, 84, 0.14);
    color: var(--deep-blue);
    font-weight: 600;
    text-decoration: none;
    font-size: 0.85rem;
}

.class-note {
    margin: 0;
    color: #BB5E35;
    font-weight: 600;
    font-size: 0.9rem;
}


.class-notes-panel {
    flex: 1 1 280px;
    max-width: none;
    width: 100%;
    background: rgba(255, 255, 255, 0.72);
    border-radius: 24px;
    padding: 1.4rem;
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.45);
    display: flex;
    flex-direction: column;
    gap: 1rem;
    order: 2;
}

.class-notes-title {
    margin: 0;
    font-size: 1rem;
    font-weight: 700;
}

.class-notes-scroll {
    height: 100%;
    max-height: 360px;
    overflow-y: auto;
    padding-right: 0.45rem;
}

.class-notes-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 1.1rem;
    position: relative;
    --timeline-x: 0.6rem;
}

.class-notes-list::before {
    content: '';
    position: absolute;
    left: var(--timeline-x);
    top: 0.3rem;
    bottom: 0.3rem;
    width: 2px;
    background: rgba(60, 42, 30, 0.12);
    transform: translateX(-50%);
}

.class-notes-list li {
    display: flex;
    gap: 0.85rem;
    position: relative;
    padding-left: 1.6rem;
    min-height: 52px;
}

.class-notes-marker {
    width: 12px;
    height: 12px;
    border-radius: 999px;
    background: var(--primary);
    position: absolute;
    left: var(--timeline-x);
    top: 0.4rem;
    transform: translateX(-50%);
    box-shadow: 0 0 0 4px rgba(255, 139, 84, 0.18);
}

.class-notes-content {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    min-width: 0;
}

.class-note-tag {
    align-self: flex-start;
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.15rem 0.5rem;
    border-radius: 999px;
    background: rgba(60, 42, 30, 0.08);
    color: rgba(60, 42, 30, 0.75);
}

.class-note-tag.is-member {
    background: rgba(220, 78, 40, 0.15);
    color: #c0392b;
}

.class-notes-list time {
    font-size: 0.85rem;
    font-weight: 700;
    color: rgba(60, 42, 30, 0.6);
}

.class-notes-list p {
    margin: 0;
    font-size: 0.95rem;
    color: rgba(60, 42, 30, 0.85);
    white-space: pre-wrap;
    overflow-wrap: anywhere;
    word-break: break-word;
    max-height: 140px;
    overflow-y: auto;
}

.class-notes-list p a {
    overflow-wrap: anywhere;
    word-break: break-word;
}

.class-notes-empty {
    margin: 0;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.6);
}

.class-toggle {
    align-self: flex-start;
    border: none;
    background: var(--deep-blue);
    color: #fff;
    padding: 0.7rem 1.4rem;
    border-radius: 999px;
    font-weight: 700;
    cursor: pointer;
    transition: background 0.25s ease, color 0.25s ease, transform 0.2s ease;
    box-shadow: 0 12px 20px rgba(60, 42, 30, 0.18);
}

.class-toggle:hover,
.class-toggle:focus {
    transform: translateY(-1px);
}

.class-toggle:focus-visible {
    outline: 2px solid var(--secondary);
    outline-offset: 2px;
}

.class-toggle[aria-expanded="true"] {
    background: var(--secondary);
    color: var(--deep-blue);
}

.class-message {
    text-align: center;
    font-weight: 600;
    color: #B96947;
    background: rgba(255, 139, 84, 0.12);
    padding: 1.2rem 1.5rem;
    border-radius: 18px;
}

.class-message.error {
    color: #b43d1d;
    background: rgba(220, 78, 40, 0.12);
}

.class-cta {
    margin: 2rem auto 0;
    max-width: min(460px, 100%);
    background: #fff;
    padding: 1.5rem;
    border-radius: 20px;
    box-shadow: 0 18px 40px rgba(60, 42, 30, 0.12);
    text-align: center;
    display: grid;
    gap: 1rem;
}

.class-cta p {
    margin: 0;
    font-weight: 600;
    color: var(--deep-blue);
}

.course-thumb-wrapper {
    position: relative;
    border-radius: 24px;
    overflow: hidden;
    aspect-ratio: 16 / 9;
}

.course-thumb {
    width: 100%;
    height: auto;
    object-fit: cover;
    display: block;
}

.course-body {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.course-card .course-title {
    font-size: clamp(1.05rem, 2.4vw, 1.3rem);
    margin: 0;
    font-family: 'Baloo 2', cursive;
    color: var(--deep-blue);
}

.course-level {
    margin: 0;
    color: #B96947;
    font-size: 0.95rem;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    font-weight: 600;
    color: #B96947;
    font-size: 0.9rem;
}

.course-action {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    padding: 0.85rem 1.2rem;
    border-radius: 999px;
    background: linear-gradient(145deg, var(--course-button-light, #FF7E37), var(--course-button-dark, #DC4E28));
    color: #fff;
    border: 1px solid var(--course-button-dark, #C03A19);
    font-weight: 700;
    text-decoration: none;
    gap: 0.5rem;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    box-shadow: 0 14px 28px var(--course-button-shadow, rgba(220, 78, 40, 0.28));
}

.course-action:hover {
    transform: translateY(-2px);
    box-shadow: 0 18px 32px var(--course-button-shadow, rgba(220, 78, 40, 0.32));
    background: linear-gradient(145deg, var(--course-button-hover-light, var(--course-button-light, #FF8750)), var(--course-button-hover-dark, var(--course-button-dark, #B53A18)));
}

.course-action .course-action-icon {
    width: 16px;
    height: 16px;
    flex: 0 0 auto;
    display: inline-block;
    background-repeat: no-repeat;
    background-size: contain;
    background-position: center;
    background-image: url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCAyNCAyNCc+PHBhdGggZmlsbD0nY3VycmVudENvbG9yJyBkPSdNOCA1djE0bDExLTd6Jy8+PC9zdmc+");
}

.lesson-playground {
    margin-bottom: 3rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    background: #fff;
    padding: 2.5rem;
    border-radius: 32px;
    box-shadow: 0 35px 80px rgba(60, 42, 30, 0.12);
}

.lesson-video {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.video-shell {
    border-radius: 24px;
    overflow: hidden;
    box-shadow: inset 0 0 0 4px rgba(255, 255, 255, 0.4);
    background: #000;
}

.video-shell iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    height: auto;
    border: none;
    display: block;
}

.video-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    min-height: clamp(200px, 45vh, 320px);
    width: 100%;
    padding: clamp(1.75rem, 3vw, 2.75rem);
    border-radius: 24px;
    text-align: center;
    background: linear-gradient(180deg, #FFF7EE 0%, #FFE5D1 100%);
    color: var(--deep-blue);
    box-shadow: 0 22px 52px rgba(60, 42, 30, 0.14);
}

.video-placeholder.locked {
    border: 2px solid rgba(255, 139, 84, 0.28);
    background: linear-gradient(180deg, #FFF1E4 0%, #FFE3CB 100%);
}

.video-placeholder p {
    margin: 0;
    font-weight: 600;
    max-width: 32ch;
    color: inherit;
}

.video-placeholder .btn-primary {
    margin-top: 0.5rem;
    box-shadow: 0 18px 36px rgba(255, 139, 84, 0.28);
    align-self: center;
}

.video-placeholder .placeholder-icon {
    width: 72px;
    height: 72px;
    border-radius: 20px;
    background: rgba(255, 139, 84, 0.18);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 16px 36px rgba(255, 139, 84, 0.18);
}

.video-placeholder .placeholder-icon svg {
    width: 48px;
    height: 48px;
}

.video-placeholder .placeholder-copy {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
    align-items: center;
    max-width: 32ch;
}

.video-placeholder .placeholder-copy h3 {
    margin: 0;
    font-size: 1.2rem;
    color: var(--deep-blue);
    font-family: 'Baloo 2', cursive;
}

.video-actions {
    margin-top: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 0.75rem;
    flex-wrap: wrap;
    width: 100%;
}

.video-actions .btn-attachment {
    margin-top: 0;
    margin-right: auto;
}

.video-controls {
    display: flex;
    gap: 0.6rem;
    margin-top: 0;
    justify-content: flex-end;
    flex-wrap: wrap;
}

.video-controls .btn {
    flex: 0 0 auto;
    min-width: 88px;
    border-radius: 999px;
    padding: 0.6rem 1.1rem;
    font-weight: 600;
    background: #FFE9DC;
    color: var(--deep-blue);
    cursor: pointer;
    text-align: center;
    text-decoration: none;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.video-controls .btn.disabled {
    opacity: 0.5;
    pointer-events: none;
}


.lesson-content {
    background: linear-gradient(180deg, #FFF7EE, #FFE7D0);
    border-radius: 24px;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.lesson-tag {
    margin: 0;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--primary);
    text-transform: uppercase;
}

.lesson-content h2 {
    margin: 0;
    font-size: 2rem;
}

.lesson-desc {
    margin: 0;
    color: #B96947;
}

.btn-primary {
    border: none;
    background: var(--secondary);
    color: var(--deep-blue);
    padding: 0.9rem 1.8rem;
    border-radius: 999px;
    font-weight: 700;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    justify-content: center;
}

.class-card .btn-primary,
.class-cta .btn-primary {
    background: linear-gradient(145deg, #FF9E6C, var(--secondary));
    box-shadow: 0 16px 30px rgba(255, 139, 84, 0.24);
}

.class-card .btn-primary {
    align-self: stretch;
    width: 100%;
    color: #fff;
}

.class-cta .btn-primary {
    align-self: center;
    color: var(--deep-blue);
}

.btn-link {
    border: none;
    background: transparent;
    color: var(--primary);
    font-weight: 700;
    cursor: pointer;
}

footer {
    margin-top: 3rem;
    background: linear-gradient(135deg, #C63C1B, #DC4E28);
    border-radius: 32px 32px 0 0;
    padding: 2.5rem 0;
    box-shadow: 0 -20px 50px rgba(60, 42, 30, 0.12);
    color: #fff;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.footer-content h4 {
    margin: 0 0 0.8rem;
    color: #fff;
}

.footer-content ul {
    list-style: none;
    padding: 0;
    margin: 0;
    color: rgba(255, 255, 255, 0.85);
}

.footer-social-list {
    display: grid;
    gap: 0.65rem;
}

.footer-social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.2s ease;
}

.footer-social-link:hover,
.footer-social-link:focus-visible {
    color: #fff;
}

.footer-social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.16);
    transition: background 0.2s ease;
}

.footer-social-link:hover .footer-social-icon,
.footer-social-link:focus-visible .footer-social-icon {
    background: rgba(255, 255, 255, 0.28);
}

.footer-social-icon svg {
    width: 18px;
    height: 18px;
    display: block;
}

/* Course detail page */
.course-hero {
    margin-bottom: clamp(1.75rem, 3vw, 2.75rem);
}

.course-hero-head {
    padding: clamp(1.25rem, 2.5vw, 1.75rem) 0;
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
}

.course-title {
    font-family: 'Baloo 2', cursive;
    margin: 0;
    font-size: clamp(1.8rem, 3.5vw, 2.6rem);
    color: var(--deep-blue);
}

.course-alert {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: #fff3eb;
    color: #bb5e35;
    padding: 0.65rem 1rem;
    border-radius: 14px;
    font-weight: 600;
    box-shadow: 0 10px 24px rgba(255, 139, 84, 0.18);
    max-width: min(720px, 100%);
}

.course-layout {
    display: grid;
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
    gap: clamp(1.5rem, 3vw, 2.75rem);
    margin-bottom: clamp(2.5rem, 4vw, 3.5rem);
    align-items: flex-start;
}

.course-player,
.lesson-sidebar {
    background: #fff;
    border-radius: 24px;
    box-shadow: 0 24px 56px rgba(60, 42, 30, 0.12);
}

.course-player {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    padding: clamp(1.5rem, 3vw, 2.5rem);
}

.video-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem 1.5rem;
    align-items: center;
    justify-content: flex-start;
}

.btn-attachment {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.55rem 1.2rem;
    border-radius: 999px;
    background: rgba(60, 42, 30, 0.08);
    color: var(--primary);
    font-weight: 700;
    text-decoration: none;
    box-shadow: 0 12px 26px rgba(220, 78, 40, 0.18);
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-attachment:hover,
.btn-attachment:focus {
    background: var(--primary);
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 16px 32px rgba(220, 78, 40, 0.28);
}

.btn-attachment svg {
    width: 18px;
    height: 18px;
}

.lesson-sidebar {
    padding: clamp(1.25rem, 2.5vw, 2rem);
    max-height: clamp(520px, 70vh, 760px);
    overflow-y: auto;
}

.lesson-sidebar h2 {
    margin-top: 0;
    font-family: 'Baloo 2', cursive;
}

.playlist-group + .playlist-group {
    margin-top: 1.5rem;
}

.group-title {
    margin: 0 0 0.6rem;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 1px;
}

.playlist-group ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 0.6rem;
}

.playlist-group li {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #fff7f0;
    border-radius: 18px;
    padding: 0.9rem 1.1rem;
    gap: 1rem;
    border: 1px solid transparent;
}

.playlist-group li.active {
    background: #fff1e4;
    border-color: rgba(220, 78, 40, 0.35);
    box-shadow: 0 8px 22px rgba(255, 139, 84, 0.22);
}

.now-playing {
    margin-top: 1.2rem;
    padding: 0.9rem 1.2rem;
    border-radius: 18px;
    background: #fff0e7;
    font-weight: 600;
    color: var(--deep-blue);
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
}

.now-playing-label {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.25rem 0.7rem;
    border-radius: 999px;
    background: rgba(220, 78, 40, 0.12);
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.6px;
}

.now-playing-title {
    font-size: 1.05rem;
}

.lesson-info {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.lesson-attachment {
    font-size: 0.85rem;
    font-weight: 700;
    color: #2e7d32;
}

.lesson-action {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.55rem 1.15rem;
    border-radius: 999px;
    text-decoration: none;
    font-weight: 700;
    color: var(--deep-blue);
    background: #fff;
    border: 1px solid rgba(60, 42, 30, 0.12);
    box-shadow: 0 10px 18px rgba(60, 42, 30, 0.1);
    transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease, color 0.2s ease;
}

.lesson-action:hover,
.lesson-action:focus {
    transform: translateY(-1px);
    box-shadow: 0 14px 26px rgba(60, 42, 30, 0.14);
}

.lesson-action svg {
    width: 16px;
    height: 16px;
}

.lesson-action.is-active {
    background: var(--secondary);
    color: var(--deep-blue);
    border-color: transparent;
}

.lesson-action.is-active svg {
    color: var(--deep-blue);
}

.playlist-group strong {
    display: block;
    font-size: 1rem;
}

.playlist-group span {
    font-size: 0.85rem;
    color: #B96947;
}

.playlist-group button {
    border: none;
    border-radius: 999px;
    padding: 0.55rem 1.2rem;
    font-weight: 600;
    background: var(--deep-blue);
    color: #fff;
    cursor: pointer;
}

.playlist-group li.active button {
    background: var(--secondary);
    color: var(--deep-blue);
}

@media (max-width: 760px) {
    .course-layout {
        grid-template-columns: 1fr;
    }

    .course-player {
        padding: 1.5rem;
    }

    .lesson-sidebar {
        padding: 1.25rem;
        max-height: clamp(360px, 65vh, 520px);
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
    }

    .class-grid {
        grid-template-columns: 1fr;
    }
    .class-card {
        flex-direction: column;
    }

    .class-card-content {
        order: 1;
    }

    .class-notes-panel {
        order: 2;
        max-width: 100%;
        width: 100%;
    }

    .class-body {
        padding: 0;
    }

}

@media (max-width: 768px) {
    .site-header {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
        text-align: center;
    }

    .btn-login,
    .header-actions {
        width: 100%;
    }

    .site-header > .btn-login {
        margin-left: 0;
    }

    .header-actions {
        justify-content: center;
        align-items: center;
    }

    .user-menu {
        width: 100%;
    }

    .user-toggle {
        width: 100%;
        justify-content: space-between;
    }

    .user-dropdown {
        position: static;
        width: 100%;
        margin-top: 0.75rem;
        box-shadow: 0 14px 32px rgba(60, 42, 30, 0.16);
    }

    .main-nav {
        width: 100%;
        flex-wrap: wrap;
        gap: 0.75rem 1rem;
        margin-bottom: 0.5rem;
        justify-content: center;
    }

    .main-nav a {
        background: #fff;
        padding: 0.5rem 0.75rem;
        justify-content: center;
    }

    .logo-block {
        width: 100%;
        justify-content: center;
    }

    .lesson-playground,
    .course-player,
    .course-hero-head {
        padding: 1.5rem;
    }

}



.blog-section {
    padding: 3rem 0 2.8rem;
    background: radial-gradient(circle at top, #fff9f3, transparent 58%);
}

.blog-section .section-heading {
    text-align: center;
    max-width: 640px;
    margin: 0 auto clamp(1.2rem, 2.6vw, 2rem);
}

.blog-list {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.5rem;
}

.blog-card {
    display: flex;
    flex-direction: column;
    background: #fff;
    border-radius: 22px;
    padding: 1.25rem;
    box-shadow: 0 12px 28px rgba(60, 42, 30, 0.12);
    position: relative;
    transition: transform 0.25s ease, box-shadow 0.25s ease;
    min-height: 100%;
    text-decoration: none;
    color: inherit;
}

.blog-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 18px 36px rgba(60, 42, 30, 0.16);
}

.blog-card.pinned {
    border: 2px solid rgba(255, 139, 84, 0.25);
}

.blog-thumb {
    position: relative;
    border-radius: 18px;
    overflow: hidden;
    background: rgba(255, 139, 84, 0.15);
    aspect-ratio: 16 / 10;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.blog-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.blog-thumb.is-placeholder {
    background: linear-gradient(135deg, rgba(255, 191, 143, 0.3), rgba(255, 139, 84, 0.18));
    color: rgba(60, 42, 30, 0.55);
}

.blog-thumb-label {
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.blog-info {
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
}

.blog-info h3 {
    margin: 0;
    font-size: clamp(1.05rem, 1.8vw, 1.25rem);
    color: #2a2019;
}

.blog-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem 0.65rem;
    font-size: 0.8rem;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.6);
}

.blog-meta span + span::before {
    content: '\2022';
    margin-right: 0.35rem;
    color: rgba(60, 42, 30, 0.35);
}

.blog-info p {
    margin: 0;
    color: rgba(60, 42, 30, 0.7);
    line-height: 1.6;
    font-size: 0.92rem;
}

.blog-link {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    margin-top: auto;
    font-size: 0.9rem;
}

.blog-link::after {
    content: '\2192';
    font-size: 0.95rem;
    transition: transform 0.2s ease;
}

.blog-link:hover {
    text-decoration: none;
}

.blog-link:hover::after {
    transform: translateX(4px);
}

.blog-badge {
    position: absolute;
    top: 0.8rem;
    left: 0.8rem;
    background: var(--primary);
    color: #fff;
    padding: 0.3rem 0.75rem;
    border-radius: 999px;
    font-weight: 700;
    font-size: 0.75rem;
    box-shadow: 0 10px 20px rgba(220, 78, 40, 0.2);
}

.blog-empty {
    text-align: center;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.65);
    background: rgba(255, 139, 84, 0.12);
    padding: 1.25rem 1.6rem;
    border-radius: 18px;
    max-width: 520px;
    margin: 0 auto;
}

.blog-pagination {
    margin-top: clamp(1.4rem, 2.4vw, 2rem);
    text-align: center;
}

.blog-pagination ul {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0;
    margin: 0;
    list-style: none;
}

.blog-pagination a,
.blog-pagination span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.1rem;
    height: 2.1rem;
    border-radius: 999px;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.7);
    background: #fff;
    box-shadow: 0 10px 24px rgba(60, 42, 30, 0.12);
    text-decoration: none;
    font-size: 0.9rem;
}

.blog-pagination span.current {
    background: var(--primary);
    color: #fff;
}

.blog-pagination a:hover {
    background: rgba(255, 139, 84, 0.15);
}

@media (max-width: 1024px) {
    .blog-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 1.25rem;
    }
}

@media (max-width: 640px) {
    .blog-list {
        grid-template-columns: 1fr;
        gap: 1.1rem;
    }

    .blog-card {
        padding: 1.1rem;
    }
}

.post-page {
    background: var(--soft-bg);
    color: var(--deep-blue);
    font-family: 'Nunito', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

.post-header {
    padding: 2.5rem 0;
    background: radial-gradient(circle at top, #fff5ec, transparent 65%);
}

.post-header .post-back {
    display: inline-flex;
    gap: 0.4rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    margin-bottom: 1rem;
}

.post-header h1 {
    margin: 0;
    font-size: clamp(1.8rem, 3vw, 2.6rem);
}

.post-meta {
    margin: 0.75rem 0 0;
    display: flex;
    gap: 0.75rem;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.65);
}

.post-meta span {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.post-content {
    max-width: 860px;
    margin: 0 auto;
    padding: 2rem 0;
}

.post-hero img {
    width: 100%;
    border-radius: 24px;
    box-shadow: 0 24px 48px rgba(60, 42, 30, 0.18);
    margin-bottom: 2rem;
}

.post-video {
    margin: 2rem 0;
}

.post-video iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    border: none;
    border-radius: 24px;
    box-shadow: 0 20px 44px rgba(60, 42, 30, 0.16);
}

.post-hero-video {
    margin: 0 0 2rem;
}

.post-video-link {
    margin: 1rem 0 2rem;
    font-weight: 600;
}

.post-video-link a {
    color: var(--primary);
    text-decoration: underline;
}

.post-excerpt {
    font-weight: 600;
    font-size: 1.05rem;
    background: rgba(255, 139, 84, 0.12);
    padding: 1.25rem 1.5rem;
    border-radius: 18px;
}

.post-body {
    margin-top: 2rem;
    line-height: 1.75;
    font-size: 1rem;
}

.post-body img {
    display: block;
    width: 100%;
    max-width: 680px;
    height: auto;
    margin: 1.5rem auto;
    border-radius: 18px;
}

.post-body figure {
    margin: 1.5rem auto;
    max-width: 700px;
}

.post-body iframe {
    display: block;
    width: 100%;
    max-width: 700px;
    margin: 1.5rem auto;
    border-radius: 18px;
}

.post-body figure > img {
    margin: 0 auto;
}

.post-body p {
    margin-bottom: 1.2rem;
}

.post-body h2,
.post-body h3,
.post-body h4 {
    margin: 2rem 0 1rem;
    font-weight: 700;
}

.post-body ul,
.post-body ol {
    margin: 0 0 1.2rem 1.25rem;
    padding-left: 1.25rem;
}

.post-body li {
    margin-bottom: 0.35rem;
}

.post-body a {
    color: var(--primary);
    text-decoration: underline;
}

.post-empty {
    text-align: center;
    font-weight: 600;
    padding: 2rem;
    background: rgba(60, 42, 30, 0.08);
    border-radius: 20px;
}

.post-related {
    padding: 2rem 0 3.5rem;
}

.post-related h2 {
    text-align: center;
    margin-bottom: 1.5rem;
}

.post-related .blog-grid {
    margin-top: 1.5rem;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.5rem;
}

.post-related .blog-card {
    max-width: 100%;
    margin: 0;
}

.post-related .blog-thumb {
    aspect-ratio: 16 / 10;
}

.post-related .blog-info h3 {
    font-size: 1.05rem;
}

.post-related .blog-link {
    font-size: 0.95rem;
}

.course-page .site-header {
    margin-bottom: 0;
}

.course-hero {
    padding: 2.75rem 0 3.25rem;
    background: radial-gradient(circle at top, rgba(255, 224, 179, 0.42), transparent 70%);
}

.course-back {
    display: inline-flex;
    gap: 0.4rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    margin-bottom: 1.5rem;
    align-items: center;
}

.course-hero-head {
    margin-bottom: 1.75rem;
}

.course-title {
    margin: 0;
    font-size: clamp(1.95rem, 4vw, 2.9rem);
    font-weight: 800;
    color: var(--deep-blue);
}

.course-hero-body {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 3rem);
    align-items: stretch;
}

.course-hero-player {
    background: #fff;
    border-radius: 28px;
    box-shadow: 0 32px 68px rgba(60, 42, 30, 0.15);
    padding: clamp(1.6rem, 3vw, 2.4rem);
    display: flex;
    flex-direction: column;
    gap: 1.4rem;
}

.course-player-media {
    border-radius: 24px;
    overflow: hidden;
    box-shadow: 0 24px 48px rgba(60, 42, 30, 0.18);
}

.course-player-media iframe,
.course-player-media img {
    width: 100%;
    aspect-ratio: 16 / 9;
    display: block;
    border: none;
    object-fit: cover;
}

.course-player-info {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.course-player-badge {
    align-self: flex-start;
    padding: 0.35rem 0.9rem;
    background: rgba(255, 139, 84, 0.18);
    color: var(--primary);
    border-radius: 999px;
    font-weight: 700;
    font-size: 0.85rem;
    letter-spacing: 0.03em;
    text-transform: uppercase;
}

.course-player-title {
    margin: 0;
    font-size: clamp(1.25rem, 2.5vw, 1.6rem);
    color: var(--deep-blue);
}

.course-player-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.course-player-action {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.7rem 1.4rem;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 700;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    box-shadow: 0 16px 32px rgba(220, 78, 40, 0.22);
}

.course-player-action:hover,
.course-player-action:focus-visible {
    transform: translateY(-1px);
    box-shadow: 0 20px 40px rgba(220, 78, 40, 0.28);
}

.course-player-action--secondary {
    background: rgba(60, 42, 30, 0.08);
    color: var(--primary);
    box-shadow: none;
}

.course-player-action--secondary:hover,
.course-player-action--secondary:focus-visible {
    background: rgba(60, 42, 30, 0.12);
    color: var(--primary);
    box-shadow: none;
}

.course-summary {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.course-summary-card {
    background: #fff;
    border-radius: 24px;
    box-shadow: 0 28px 60px rgba(60, 42, 30, 0.12);
    padding: clamp(1.4rem, 2.5vw, 2rem);
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.course-status {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.45rem 1rem;
    border-radius: 999px;
    font-weight: 700;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    align-self: flex-start;
}

.course-status.is-live {
    background: rgba(220, 78, 40, 0.16);
    color: var(--primary);
}

.course-status.is-progress {
    background: rgba(54, 119, 246, 0.15);
    color: #1854d1;
}

.course-status.is-draft {
    background: rgba(60, 42, 30, 0.12);
    color: rgba(60, 42, 30, 0.75);
}

.course-summary-meta {
    display: grid;
    gap: 1rem;
}

.course-summary-item {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 0.85rem;
    align-items: baseline;
    font-weight: 600;
    color: rgba(60, 42, 30, 0.8);
}

.course-summary-item dt {
    font-weight: 700;
    color: rgba(60, 42, 30, 0.65);
    text-transform: uppercase;
    font-size: 0.78rem;
    letter-spacing: 0.08em;
}

.course-summary-item dd {
    margin: 0;
    font-size: 0.95rem;
}

.course-summary-outline h2 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--deep-blue);
}

.outline-nav-title {
    margin: 1rem 0 0.35rem;
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.outline-nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.55rem;
}

.outline-nav-list li a {
    display: flex;
    flex-direction: column;
    gap: 0.1rem;
    padding: 0.75rem 0.9rem;
    border-radius: 16px;
    background: rgba(60, 42, 30, 0.05);
    color: inherit;
    text-decoration: none;
    transition: background 0.2s ease, transform 0.2s ease;
}

.outline-nav-list li a span {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: rgba(60, 42, 30, 0.65);
}

.outline-nav-list li a strong {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--deep-blue);
}

.outline-nav-list li a:hover,
.outline-nav-list li a:focus-visible {
    background: rgba(255, 139, 84, 0.18);
    transform: translateX(4px);
    color: var(--deep-blue);
}

.course-content {
    padding: 2.75rem 0 3.75rem;
}

.course-outline > h2 {
    margin: 0;
    font-size: clamp(1.6rem, 2.6vw, 2.1rem);
}

.course-outline-sections {
    margin-top: 2rem;
    display: grid;
    gap: 2.25rem;
}

.course-outline-section {
    display: grid;
    gap: 1.25rem;
}

.course-outline-title {
    margin: 0;
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--primary);
}

.course-outline-lessons {
    display: grid;
    gap: 1.5rem;
}

.course-lesson {
    background: #fff;
    border-radius: 24px;
    padding: clamp(1.5rem, 3vw, 2rem);
    box-shadow: 0 28px 60px rgba(60, 42, 30, 0.12);
    scroll-margin-top: 140px;
    display: grid;
    gap: 1.1rem;
}

.course-lesson-header {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
}

.course-lesson-index {
    align-self: flex-start;
    padding: 0.3rem 0.85rem;
    border-radius: 999px;
    background: rgba(255, 139, 84, 0.2);
    color: var(--primary);
    font-weight: 700;
    font-size: 0.82rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.course-lesson-heading {
    margin: 0;
    font-size: 1.2rem;
    color: var(--deep-blue);
}

.course-lesson-media {
    border-radius: 22px;
    overflow: hidden;
    box-shadow: 0 22px 46px rgba(60, 42, 30, 0.14);
}

.course-lesson-media iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    border: none;
}

.course-lesson-link,
.course-lesson-attachment {
    margin: 0;
    font-weight: 600;
}

.course-lesson-link a,
.course-lesson-attachment a {
    color: var(--primary);
    text-decoration: underline;
}

.course-empty {
    text-align: center;
    background: rgba(60, 42, 30, 0.08);
    border-radius: 22px;
    padding: 2.25rem;
    font-weight: 600;
}

@media (max-width: 1080px) {
    .course-hero-body {
        grid-template-columns: 1fr;
    }

    .course-summary {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .course-summary-card {
        flex: 1 1 260px;
    }
}

/* Course detail redesign */
.course-shell {
    background: var(--soft-bg);
    padding-bottom: 4rem;
}

.course-shell-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
    padding: 2.5rem 0 1.75rem;
}

.course-shell-head .course-title {
    margin: 0;
    font-size: clamp(1.9rem, 2.8vw, 2.6rem);
    line-height: 1.25;
    color: var(--deep-blue);
}

.course-back {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.65rem 1.2rem;
    background: #fff;
    border-radius: 999px;
    border: 1px solid rgba(60, 42, 30, 0.12);
    color: var(--primary);
    font-weight: 700;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.course-back:hover,
.course-back:focus-visible {
    transform: translateY(-1px);
    box-shadow: 0 10px 22px rgba(220, 78, 40, 0.18);
    border-color: rgba(220, 78, 40, 0.4);
    outline: none;
}

.course-section {
    padding: 0 0 3.5rem;
}

.course-message-card {
    background: #fff;
    border-radius: 28px;
    padding: clamp(2rem, 4vw, 3rem);
    margin: 0 auto;
    max-width: 620px;
    text-align: center;
    box-shadow: 0 32px 64px rgba(60, 42, 30, 0.16);
}

.course-message-card.is-error {
    border: 1px solid rgba(220, 78, 40, 0.5);
}

.course-message-card h2 {
    margin: 0;
    font-size: clamp(1.5rem, 2.6vw, 2rem);
    color: var(--deep-blue);
}

.course-message-card p {
    margin: 0.75rem 0 0;
    color: rgba(60, 42, 30, 0.75);
    font-size: 1rem;
}

.course-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.75fr) minmax(0, 1fr);
    gap: clamp(1.75rem, 3.5vw, 2.75rem);
    align-items: flex-start;
    padding-bottom: clamp(2rem, 4vw, 3.5rem);
}

.course-player-column {
    display: flex;
    flex-direction: column;
    gap: clamp(1.5rem, 3vw, 2rem);
}

.course-player-card {
    background: #fff;
    border-radius: 30px;
    box-shadow: 0 36px 72px rgba(60, 42, 30, 0.15);
    padding: clamp(1.75rem, 3vw, 2.5rem);
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
    position: sticky;
    top: clamp(1rem, 3vw, 2rem);
    z-index: 5;
}

.course-player-header {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.course-player-badge {
    align-self: flex-start;
    background: rgba(220, 78, 40, 0.15);
    color: var(--primary);
    border-radius: 999px;
    padding: 0.3rem 0.9rem;
    font-weight: 700;
    font-size: 0.85rem;
    letter-spacing: 0.02em;
}

.course-player-title {
    margin: 0;
    font-size: clamp(1.6rem, 2.5vw, 2.1rem);
    color: var(--deep-blue);
    line-height: 1.3;
}

.course-video-wrapper {
    position: relative;
    border-radius: 26px;
    overflow: hidden;
    background: #000;
    box-shadow: inset 0 0 0 1px rgba(60, 42, 30, 0.05);
}

.course-video-wrapper iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    border: none;
    display: block;
}

.course-video-fallback,
.course-video-placeholder,
.course-video-locked {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.25rem;
    padding: clamp(2.5rem, 4vw, 3.5rem) clamp(1.5rem, 3vw, 2.5rem);
    text-align: center;
    background: #fff;
    color: var(--deep-blue);
}

.course-video-placeholder img {
    width: min(320px, 70%);
    border-radius: 20px;
    object-fit: cover;
    box-shadow: 0 24px 48px rgba(60, 42, 30, 0.18);
}

.course-video-fallback.is-hidden,
.course-video-placeholder.is-hidden {
    display: none;
}

.course-video-locked p {
    margin: 0;
    font-size: 1.05rem;
    color: rgba(60, 42, 30, 0.82);
}

.course-player-attachments {
    border: 1px solid rgba(60, 42, 30, 0.15);
    border-radius: 18px;
    padding: 0.9rem 1.25rem;
    background: rgba(255, 247, 238, 0.65);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 1rem;
}

.course-player-attachments[hidden] {
    display: none;
}

.course-player-attachments-title {
    margin: 0;
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--deep-blue);
}

.course-player-attachments-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
}

.course-player-attachments-list li a {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    text-decoration: none;
    font-weight: 600;
    color: var(--primary);
    padding: 0.5rem 0.8rem;
    border-radius: 12px;
    background: rgba(220, 78, 40, 0.08);
    transition: background 0.2s ease, color 0.2s ease;
}

.course-player-attachments-list li a:hover,
.course-player-attachments-list li a:focus-visible {
    background: rgba(220, 78, 40, 0.2);
    color: var(--secondary);
    outline: none;
}

.course-player-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
    width: 100%;
    margin-top: 1rem;
}

.course-player-controls [data-player-next] {
    margin-left: auto;
}

.course-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.75rem 1.6rem;
    border-radius: 999px;
    border: 1px solid rgba(60, 42, 30, 0.2);
    background: #fff;
    color: var(--deep-blue);
    font-weight: 700;
    font-size: 0.95rem;
    text-decoration: none;
    transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
    cursor: pointer;
}

.course-btn:hover,
.course-btn:focus-visible {
    background: var(--deep-blue);
    color: #fff;
    border-color: transparent;
    box-shadow: 0 18px 32px rgba(60, 42, 30, 0.2);
    outline: none;
}

.course-btn.primary {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
    box-shadow: 0 20px 36px rgba(220, 78, 40, 0.24);
}

.course-btn.primary:hover,
.course-btn.primary:focus-visible {
    background: var(--secondary);
    border-color: var(--secondary);
}

.course-btn[disabled] {
    opacity: 0.5;
    cursor: not-allowed;
    box-shadow: none;
}

.course-info-card {
    background: #fff;
    border-radius: 26px;
    box-shadow: 0 28px 56px rgba(60, 42, 30, 0.12);
    padding: clamp(1.6rem, 3vw, 2.2rem);
}

.course-info-card h3 {
    margin: 0 0 1.1rem;
    font-size: 1.25rem;
    color: var(--deep-blue);
}

.course-info-list {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
    margin: 0;
}

.course-info-item {
    display: grid;
    grid-template-columns: minmax(120px, auto) 1fr;
    gap: 0.65rem;
    align-items: center;
    font-size: 0.95rem;
    color: rgba(60, 42, 30, 0.78);
}

.course-outline-panel {
    background: #fff;
    border-radius: 32px;
    box-shadow: 0 36px 72px rgba(60, 42, 30, 0.14);
    padding: clamp(1.8rem, 3vw, 2.4rem);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    position: sticky;
    top: clamp(1rem, 3vw, 2rem);
    max-height: calc(100vh - 2.5rem);
    align-self: flex-start;
    height: auto;
    height: min(var(--course-outline-height, 9999px), calc(100vh - 2.5rem));
    overflow: hidden;
}

.course-outline-header h2 {
    margin: 0;
    font-size: 1.45rem;
    color: var(--deep-blue);
}

.course-outline-note {
    margin: 0.35rem 0 0;
    font-size: 0.9rem;
    color: rgba(60, 42, 30, 0.65);
}

.course-outline-list {
    flex: 1;
    overflow-y: auto;
    padding-right: 0.5rem;
}

.course-outline-list::-webkit-scrollbar {
    width: 6px;
}

.course-outline-list::-webkit-scrollbar-thumb {
    background: rgba(60, 42, 30, 0.18);
    border-radius: 999px;
}

.outline-section + .outline-section {
    margin-top: 1.5rem;
}

.outline-section-title {
    margin: 0 0 0.85rem;
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary);
}

.outline-lessons {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.outline-lesson {
    border: none;
    width: 100%;
    text-align: left;
    background: #fff;
    border-radius: 20px;
    padding: 0.95rem 1.15rem;
    box-shadow: 0 18px 32px rgba(60, 42, 30, 0.1);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.25rem;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    color: var(--deep-blue);
}

.outline-lesson:hover,
.outline-lesson:focus-visible {
    transform: translateY(-2px);
    box-shadow: 0 22px 42px rgba(60, 42, 30, 0.16);
    outline: none;
}

.outline-lesson.is-active {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    box-shadow: 0 26px 48px rgba(220, 78, 40, 0.24);
}

.outline-lesson-text {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.outline-lesson-number {
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    opacity: 0.7;
}

.outline-lesson.is-active .outline-lesson-number {
    opacity: 0.9;
}

.outline-lesson-title-text {
    font-weight: 700;
    font-size: 1rem;
}

.outline-lesson-action {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.45rem;
    border-radius: 999px;
    border: 1px solid currentColor;
    padding: 0.35rem 1rem;
    font-size: 0.88rem;
    font-weight: 700;
    min-width: 100px;
    text-align: center;
    transition: background 0.2s ease, color 0.2s ease;
    position: relative;
}

.outline-lesson.is-active .outline-lesson-action {
    background: #fff;
    color: var(--primary);
}

.outline-lesson-attachment-icon {
    width: 0.85rem;
    height: 1rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.outline-lesson-attachment-icon svg {
    width: 100%;
    height: 100%;
    fill: currentColor;
}

.outline-lesson-action-label {
    display: inline-block;
}

.course-outline-empty {
    margin: 0;
    color: rgba(60, 42, 30, 0.68);
    font-size: 0.95rem;
}

@media (max-width: 1100px) {
    .course-layout {
        grid-template-columns: 1fr;
    }

    .course-outline-panel,
    .course-player-card {
        position: static;
        max-height: none;
        height: auto;
    }

    .course-outline-panel {
        order: 2;
        overflow: visible;
    }

    .course-player-column {
        height: auto;
    }
}

@media (max-width: 768px) {
    .course-shell-head {
        flex-direction: column;
        align-items: flex-start;
    }

    .course-player-column {
        display: contents;
    }

    .course-player-card {
        position: sticky;
        top: 0;
        z-index: 20;
        margin-bottom: 1.5rem;
    }

    .course-outline-panel {
        padding: 1.5rem;
    }

    .course-player-controls {
        align-items: stretch;
    }

    .course-btn {
        flex: 1 1 100%;
        justify-content: center;
    }

    .course-player-controls [data-player-next] {
        margin-left: 0;
    }

    .course-outline-list {
        max-height: 60vh;
    }
}

@media (max-width: 520px) {
    .course-player-card {
        padding: 1.5rem;
        border-radius: 24px;
    }

    .course-info-card {
        padding: 1.4rem;
        border-radius: 22px;
    }

    .outline-lesson {
        padding: 0.85rem 1rem;
        border-radius: 16px;
    }

    .outline-lesson-action {
        min-width: 84px;
    }
}

@media (max-width: 1024px) {
    .post-related .blog-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 640px) {
    .post-related .blog-grid {
        grid-template-columns: 1fr;
    }
}

.back-to-top {
    position: fixed;
    right: 24px;
    bottom: 24px;
    width: 54px;
    height: 54px;
    border: none;
    border-radius: 50%;
    background: linear-gradient(135deg, #ff3d83, #ff007a);
    box-shadow: 0 12px 24px rgba(255, 0, 122, 0.3);
    color: #fff;
    font-size: 26px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translate3d(0, 18px, 0);
    transition: opacity 0.25s ease, visibility 0.25s ease, transform 0.25s ease;
    z-index: 999;
}

.back-to-top:focus-visible {
    outline: 3px solid rgba(255, 255, 255, 0.8);
    outline-offset: 4px;
}

.back-to-top.is-visible {
    opacity: 1;
    visibility: visible;
    transform: translate3d(0, 0, 0);
}

.back-to-top span {
    line-height: 1;
}

@media (max-width: 768px) {
    .back-to-top {
        right: 16px;
        bottom: 16px;
        width: 48px;
        height: 48px;
        font-size: 22px;
    }
}