:root {
    --accent-yellow: #ffe934;
    --accent-orange: #ff9f1c;
    --accent-fire: #f24a18;
    --accent-red: #d91f27;
    --accent-rose: #cf1f54;
    --accent-pink: #d23d97;
    --accent-purple: #8e44ad;
    --accent-violet: #6437b7;
    --accent-indigo: #4f42c9;
    --primary-blue: #1f6fd1;
    --primary-blue-dark: #1746a2;
    --primary-blue-soft: #eaf4ff;
    --ink: #111827;
    --muted: #667085;
    --line: #e7edf5;
    --paper: #ffffff;
    --soft: #f8fbff;
}

body {
    background: #ffffff !important;
    color: var(--ink);
}

.course-detail-page {
    display: grid;
    gap: 2rem;
}

.course-hero {
    position: relative;
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 1.5rem;
    align-items: center;
    overflow: hidden;
    border: 1px solid rgba(31, 111, 209, 0.12);
    border-radius: 28px;
    background:
        linear-gradient(125deg, rgba(232, 244, 255, 0.98) 0%, rgba(245, 250, 255, 0.96) 48%, rgba(226, 239, 255, 0.94) 100%),
        linear-gradient(90deg, rgba(255, 233, 52, 0.18), rgba(210, 61, 151, 0.08), rgba(31, 111, 209, 0.18));
    box-shadow: 0 24px 72px rgba(31, 111, 209, 0.08);
    padding: clamp(1.25rem, 3vw, 1.85rem);
}

.course-hero::before {
    content: "";
    position: absolute;
    inset: 0 0 auto;
    height: 7px;
    background: linear-gradient(
        90deg,
        var(--accent-yellow),
        var(--accent-orange),
        var(--accent-fire),
        var(--accent-red),
        var(--accent-rose),
        var(--accent-pink),
        var(--accent-purple),
        var(--accent-violet),
        var(--accent-indigo),
        var(--primary-blue)
    );
}

.course-hero::after {
    content: "";
    position: absolute;
    right: -18%;
    bottom: -46%;
    width: 56%;
    height: 72%;
    border-radius: 999px;
    background: rgba(31, 111, 209, 0.06);
}

.course-hero__main,
.course-enroll-card {
    position: relative;
    z-index: 1;
}

.course-back-link,
.course-badges span,
.lesson-tags span {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
}

.course-back-link {
    color: var(--primary-blue);
    font-size: 0.92rem;
    font-weight: 850;
}

.course-back-link:hover {
    color: var(--primary-blue-dark);
}

.course-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    margin-top: 1rem;
}

.course-badges span {
    border: 1px solid rgba(31, 111, 209, 0.14);
    border-radius: 999px;
    background: #ffffff;
    color: var(--primary-blue);
    font-size: 0.76rem;
    font-weight: 900;
    padding: 0.42rem 0.75rem;
    box-shadow: 0 8px 22px rgba(31, 111, 209, 0.055);
}

.course-hero h1 {
    max-width: 820px;
    color: var(--primary-blue-dark);
    font-size: clamp(1.8rem, 3.2vw, 2.65rem);
    font-weight: 950;
    line-height: 1.06;
    margin: 0.65rem 0 0;
}

.course-hero p {
    max-width: 760px;
    color: var(--muted);
    font-size: 0.95rem;
    line-height: 1.8;
    margin: 0.55rem 0 0;
}

.course-teacher {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    margin-top: 1rem;
}

.course-teacher__avatar {
    display: grid;
    place-items: center;
    width: 52px;
    height: 52px;
    border-radius: 18px;
    background: linear-gradient(135deg, var(--primary-blue), var(--accent-indigo));
    color: #ffffff;
    font-size: 1.05rem;
    font-weight: 950;
    box-shadow: 0 14px 28px rgba(31, 111, 209, 0.18);
}

.course-teacher__avatar img {
    width: 100%;
    height: 100%;
    border-radius: inherit;
    object-fit: cover;
}

.course-teacher span,
.course-enroll-card__header span,
.course-metrics span {
    color: var(--muted);
    font-size: 0.85rem;
    font-weight: 750;
}

.course-teacher strong,
.course-enroll-card__header strong {
    display: block;
    color: var(--ink);
    font-weight: 900;
}

.course-enroll-card,
.curriculum-panel,
.side-card,
.course-empty {
    border: 1px solid var(--line);
    border-radius: 22px;
    background: var(--paper);
    box-shadow: 0 14px 36px rgba(31, 111, 209, 0.055);
}

.course-enroll-card {
    padding: 1.25rem;
}

.course-enroll-card__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.course-enroll-card__header strong {
    font-size: 1.25rem;
    margin-top: 0.15rem;
}

.course-enroll-card__icon {
    display: grid;
    place-items: center;
    width: 52px;
    height: 52px;
    border-radius: 18px;
    background: var(--primary-blue-soft);
    color: var(--primary-blue);
}

.course-metrics {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.75rem;
    margin-top: 1.2rem;
}

.course-metrics div {
    border-radius: 16px;
    background: var(--soft);
    padding: 1rem;
}

.course-metrics strong {
    display: block;
    color: var(--ink);
    font-size: 1.65rem;
    font-weight: 950;
    line-height: 1;
}

.course-action {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    width: 100%;
    border-radius: 14px;
    font-size: 0.95rem;
    font-weight: 850;
    min-height: 48px;
    margin-top: 1.2rem;
    padding: 0.85rem 1rem;
    transition: background 180ms ease, transform 180ms ease;
}

.course-action:hover {
    transform: translateY(-2px);
}

.course-action--primary {
    background: var(--primary-blue);
    color: #ffffff;
    box-shadow: 0 16px 34px rgba(31, 111, 209, 0.24);
}

.course-action--primary:hover {
    background: var(--primary-blue-dark);
}

.course-action--success {
    background: var(--primary-blue-soft);
    color: var(--primary-blue);
}

.course-action--pending {
    background: rgba(255, 159, 28, 0.13);
    color: #c96200;
}

.course-content-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 1.5rem;
    align-items: start;
}

.curriculum-panel {
    overflow: hidden;
}

.panel-header {
    border-bottom: 1px solid var(--line);
    padding: 1.35rem 1.5rem;
}

.panel-header span {
    color: var(--primary-blue);
    font-size: 0.78rem;
    font-weight: 950;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.panel-header h2,
.side-card h2,
.course-empty h3 {
    color: var(--ink);
    font-weight: 950;
}

.panel-header h2 {
    font-size: 1.65rem;
    margin-top: 0.2rem;
}

.lesson-list {
    display: grid;
}

.lesson-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.25rem;
    border-bottom: 1px solid var(--line);
    padding: 1.15rem 1.5rem;
    transition: background 180ms ease;
}

.lesson-item:last-child {
    border-bottom: 0;
}

.lesson-item:hover {
    background: rgba(234, 244, 255, 0.55);
}

.lesson-item__main {
    display: flex;
    min-width: 0;
    gap: 1rem;
}

.lesson-number {
    display: grid;
    place-items: center;
    flex: 0 0 auto;
    width: 46px;
    height: 46px;
    border-radius: 16px;
    background: var(--primary-blue-soft);
    color: var(--primary-blue);
    font-size: 0.95rem;
    font-weight: 950;
}

.lesson-copy {
    min-width: 0;
}

.lesson-copy h3 {
    color: var(--ink);
    font-size: 1rem;
    font-weight: 950;
    line-height: 1.35;
    word-break: break-word;
    overflow-wrap: break-word;
}

.lesson-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    margin-top: 0.55rem;
}

.lesson-tags span {
    border-radius: 999px;
    background: var(--soft);
    color: var(--muted);
    font-size: 0.75rem;
    font-weight: 800;
    padding: 0.35rem 0.62rem;
}

.lesson-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
    gap: 0.45rem;
    border-radius: 13px;
    background: var(--primary-blue);
    color: #ffffff;
    font-size: 0.88rem;
    font-weight: 850;
    min-height: 42px;
    padding: 0.65rem 0.95rem;
}

.lesson-link:hover {
    background: var(--primary-blue-dark);
}

.lesson-link--success {
    background: #16a34a;
}

.lesson-link--success:hover {
    background: #15803d;
}

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

.side-card {
    padding: 1.35rem;
}

.side-card h2 {
    font-size: 1.15rem;
}

.summary-list {
    display: grid;
    gap: 1rem;
    margin-top: 1.15rem;
}

.summary-list div {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 0.75rem;
}

.summary-list dt {
    color: var(--muted);
    font-size: 0.88rem;
    font-weight: 750;
    flex-shrink: 0;
}

.summary-list dd {
    color: var(--ink);
    font-size: 0.88rem;
    font-weight: 900;
    margin: 0;
    text-align: right;
    word-break: break-word;
    overflow-wrap: break-word;
    white-space: normal;
}

.side-card__icon {
    display: grid;
    place-items: center;
    width: 52px;
    height: 52px;
    border-radius: 18px;
    background: rgba(255, 159, 28, 0.13);
    color: #c96200;
}

.side-card--tip .side-card__header {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    margin-bottom: 0.75rem;
}

.side-card--tip .side-card__icon {
    width: 44px;
    height: 44px;
    border-radius: 14px;
    flex-shrink: 0;
}

.side-card--tip h2 {
    margin: 0;
    font-size: 1.12rem;
    font-weight: 950;
    color: var(--ink);
}

.side-card--tip p {
    color: var(--muted);
    font-size: 0.9rem;
    line-height: 1.65;
    margin: 0;
}

.course-empty {
    margin: 1.5rem;
    padding: 3rem 1.5rem;
    text-align: center;
}

.course-empty i {
    display: grid;
    place-items: center;
    width: 58px;
    height: 58px;
    border-radius: 18px;
    background: var(--primary-blue-soft);
    color: var(--primary-blue);
    font-size: 1.4rem;
    margin: 0 auto 1rem;
}

.course-empty p {
    color: var(--muted);
    margin-top: 0.25rem;
}

.course-empty--locked {
    margin: 0;
    border: 0;
    border-radius: 0;
    box-shadow: none;
}

/* ── Comprehensive Responsive Media Queries ── */

/* Laptop / Large Tablet (1024px and below) */
@media (max-width: 1024px) {
    .course-hero {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .course-content-layout {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .course-enroll-card {
        max-width: 100%;
    }

    /* Sidebar goes below curriculum on tablet */
    .course-sidebar {
        display: grid;
        grid-template-columns: 1fr;
    }
}

/* Tablet / iPad (768px and below) */
@media (max-width: 768px) {
    .course-detail-page {
        gap: 1.25rem;
    }

    .course-hero {
        border-radius: 20px;
        padding: 1.25rem;
    }

    .course-hero h1 {
        font-size: 1.5rem;
    }

    .course-content-layout {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

    .curriculum-panel {
        border-radius: 18px;
    }

    .panel-header {
        padding: 1rem 1.15rem;
    }

    .panel-header h2 {
        font-size: 1.2rem;
        margin-top: 0.15rem;
    }

    /* Lesson items: info full width, button compact */
    .lesson-item {
        flex-wrap: wrap;
        align-items: center;
        gap: 0.75rem;
        padding: 1rem 1.15rem;
    }

    .lesson-item__main {
        flex: 1 1 100%;
        align-items: flex-start;
    }

    .lesson-link {
        flex: 0 0 auto;
        width: auto;
        margin-left: auto;
        justify-content: center;
        text-align: center;
        min-height: 36px;
        font-size: 0.82rem;
        padding: 0.45rem 0.9rem;
        border-radius: 10px;
    }

    .course-metrics {
        gap: 0.5rem;
    }

    .side-card {
        border-radius: 18px;
    }
}

/* Mobile (480px and below) */
@media (max-width: 480px) {
    .course-detail-page {
        gap: 1rem;
    }

    .course-hero {
        padding: 1rem;
        border-radius: 16px;
    }

    .course-hero h1 {
        font-size: 1.3rem;
    }

    .course-hero p {
        font-size: 0.88rem;
    }

    .course-badges {
        gap: 0.4rem;
        margin-top: 0.75rem;
    }

    .course-badges span {
        font-size: 0.7rem;
        padding: 0.3rem 0.55rem;
    }

    .course-metrics > div {
        padding: 0.65rem 0.4rem;
    }

    .course-metrics strong {
        font-size: 1.2rem;
    }

    .course-metrics span {
        font-size: 0.72rem;
    }

    .curriculum-panel {
        border-radius: 14px;
    }

    .panel-header {
        padding: 0.85rem 1rem;
    }

    .panel-header h2 {
        font-size: 1.05rem;
    }

    .lesson-item {
        padding: 0.9rem 1rem;
        gap: 0.75rem;
    }

    .lesson-number {
        width: 38px;
        height: 38px;
        border-radius: 12px;
        font-size: 0.85rem;
    }

    .lesson-copy h3 {
        font-size: 0.92rem;
    }

    .lesson-tags span {
        font-size: 0.7rem;
        padding: 0.28rem 0.5rem;
    }

    .lesson-link {
        font-size: 0.78rem;
        min-height: 32px;
        padding: 0.38rem 0.75rem;
        border-radius: 8px;
    }

    .side-card {
        padding: 1rem;
        border-radius: 14px;
    }

    .course-empty {
        margin: 1rem;
        padding: 2rem 1rem;
    }
}

/* Extra small phones (360px and below) */
@media (max-width: 360px) {
    .course-hero h1 {
        font-size: 1.15rem;
    }

    .lesson-item {
        padding: 0.8rem;
    }

    .lesson-number {
        width: 34px;
        height: 34px;
        font-size: 0.78rem;
    }

    .lesson-copy h3 {
        font-size: 0.86rem;
    }
}