/* ============================================================
   COURSES.CSS
   Covers:
   1. What We Build (dark section on index)
   2. Inline Course Catalog (on index)
   3. Contact section (Ichie's two-column layout)
   4. Udemy-style Course Player (courses.html) - PREMIUM DARK MODE
   All tokens inherited from styles.css
   ============================================================ */

/* ============================================================
   1. WHAT WE BUILD — dark section
   ============================================================ */

#what-we-build {
    background: linear-gradient(to bottom, var(--clr-secondary) 0%, var(--clr-primary) 100%);
    color: var(--clr-text-light);
    padding-block: var(--spacing-xl);
}

.wwb-header {
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.wwb-header .lx-sub {
    font-family: var(--ff-body);
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--clr-accent);
    margin-bottom: 0.5rem;
    opacity: 0.95;
}

.wwb-header .lx-main,
#what-we-build h2.lx-main {
    font-family: var(--ff-header);
    font-size: clamp(1.6rem, 3.5vw, 2.25rem);
    font-weight: var(--fw-medium);
    color: var(--clr-text-light);
    margin-bottom: 0.75rem;
    line-height: 1.15;
}

.wwb-header .lx-body,
#what-we-build p.lx-body {
    font-family: var(--ff-body);
    font-size: 1.05rem;
    color: rgba(255, 247, 247, 0.8);
    font-style: italic;
}

/* Module picker tabs */
.wwb-tabs {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.wwb-tab {
    padding: 0.5rem 1.2rem;
    border-radius: 100px;
    border: 1.5px solid rgba(255, 255, 255, 0.2);
    background: transparent;
    color: rgba(255, 255, 255, 0.65);
    font-family: var(--ff-body);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: border-color 0.2s ease, color 0.2s ease, background 0.2s ease;
}

.wwb-tab:hover {
    border-color: var(--clr-accent);
    color: var(--clr-accent);
}

.wwb-tab.active {
    background: var(--clr-accent);
    border-color: var(--clr-accent);
    color: var(--clr-primary);
}

/* Browser chrome frame */
.wwb-frame-wrap {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 0.75rem;
    overflow: hidden;
}

.wwb-frame-header {
    background: rgba(0, 0, 0, 0.2);
    padding: 0.65rem 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.45rem;
}

.wwb-frame-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}
.wwb-frame-dot:nth-child(1) { background: #ff5f56; }
.wwb-frame-dot:nth-child(2) { background: #ffbd2e; }
.wwb-frame-dot:nth-child(3) { background: #27c93f; }

.wwb-frame-url {
    flex: 1;
    background: rgba(255, 255, 255, 0.07);
    border-radius: 4px;
    padding: 0.2rem 0.7rem;
    font-size: 0.78rem;
    color: rgba(255, 255, 255, 0.45);
    font-family: monospace;
}

.wwb-iframe-container {
    position: relative;
    width: 100%;
    height: 520px;
}

.wwb-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

.wwb-placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    background: rgba(0, 44, 57, 0.55);
    color: rgba(255, 255, 255, 0.6);
    text-align: center;
    padding: 2rem;
}

.wwb-placeholder-icon {
    width: 60px;
    height: 60px;
    border: 2px dashed rgba(0, 193, 142, 0.4);
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 0.5rem;
}

.wwb-placeholder-icon svg {
    width: 28px;
    height: 28px;
    stroke: var(--clr-accent);
    fill: none;
}

.wwb-placeholder h3 {
    font-family: var(--ff-header);
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.8);
}

.wwb-placeholder p {
    font-family: var(--ff-body);
    font-size: 0.9rem;
    max-width: 320px;
}

/* Meta row */
.wwb-meta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.wwb-meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--ff-body);
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.65);
}

.wwb-meta-item svg {
    width: 18px;
    height: 18px;
    stroke: var(--clr-accent);
    fill: none;
    flex-shrink: 0;
}

@media (max-width: 600px) {
    .wwb-iframe-container { height: 360px; }
}

/* ============================================================
   2. INLINE COURSE CATALOG
   ============================================================ */

#course-catalog-inline {
    background-color: var(--clr-bg);
    padding-block: var(--spacing-xl);
}

.catalog-section-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.catalog-section-header .lx-sub {
    font-family: var(--ff-body);
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--clr-accent);
    margin-bottom: 0.5rem;
}

.catalog-main-heading {
    font-family: var(--ff-header);
    font-size: clamp(1.5rem, 3vw, 2rem);
    font-weight: var(--fw-medium);
    color: var(--clr-primary);
    margin-bottom: 0.75rem;
}

.catalog-section-header .lx-body {
    font-family: var(--ff-body);
    font-size: 1rem;
    color: rgba(0, 44, 57, 0.65);
}

/* Grid */
.catalog-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

/* Card */
.catalog-card {
    background: #fff;
    border: 1px solid rgba(0, 44, 57, 0.1);
    border-radius: 0.75rem;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: box-shadow 0.3s ease, transform 0.3s ease;
    /* scroll reveal */
    opacity: 0;
    transform: translateY(20px);
}

.catalog-card.is-visible {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1),
                transform 0.6s cubic-bezier(0.4, 0, 0.2, 1),
                box-shadow 0.3s ease;
}

.catalog-card:not(.catalog-card--soon):hover {
    box-shadow: 0 8px 32px rgba(0, 44, 57, 0.12);
    transform: translateY(-3px);
}

.catalog-card--soon {
    opacity: 0.65 !important;
    pointer-events: none;
}

.catalog-card:nth-child(1) { transition-delay: 0.05s; }
.catalog-card:nth-child(2) { transition-delay: 0.12s; }
.catalog-card:nth-child(3) { transition-delay: 0.19s; }
.catalog-card:nth-child(4) { transition-delay: 0.26s; }

/* Thumbnail */
.catalog-thumb {
    width: 100%;
    height: 160px;
    background: linear-gradient(135deg, var(--clr-secondary), var(--clr-primary));
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.catalog-thumb::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, transparent 60%, rgba(0,0,0,0.25));
}

.catalog-thumb--alt {
    background: linear-gradient(135deg, #014a5c, var(--clr-primary));
}

.catalog-thumb--soon {
    background: linear-gradient(135deg, #2a2a2a, #111);
}

.catalog-thumb-icon {
    width: 52px;
    height: 52px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 1;
}

.catalog-thumb-icon svg {
    width: 26px;
    height: 26px;
    stroke: var(--clr-accent);
    fill: none;
}

/* Badge on thumb */
.catalog-badge {
    position: absolute;
    top: 0.85rem;
    left: 0.85rem;
    z-index: 2;
    font-family: var(--ff-body);
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    padding: 0.22rem 0.6rem;
    border-radius: 100px;
}

.badge-available {
    background: var(--clr-accent);
    color: var(--clr-primary);
}

.badge-soon {
    background: rgba(255, 255, 255, 0.18);
    color: rgba(255, 255, 255, 0.85);
    border: 1px solid rgba(255, 255, 255, 0.25);
}

/* Card body */
.catalog-body {
    padding: 1.35rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
}

.catalog-title {
    font-family: var(--ff-header);
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    text-transform: uppercase;
    color: var(--clr-primary);
    line-height: 1.3;
    margin: 0;
}

.catalog-desc {
    font-family: var(--ff-body);
    font-size: 0.88rem;
    color: rgba(0, 44, 57, 0.65);
    line-height: 1.55;
    flex: 1;
    margin: 0;
}

/* Objectives box */
.catalog-objectives {
    background: rgba(0, 44, 57, 0.03);
    border-left: 3px solid var(--clr-accent);
    border-radius: 0 0.35rem 0.35rem 0;
    padding: 0.65rem 0.9rem;
}

.catalog-objectives h4 {
    font-family: var(--ff-body);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.09em;
    text-transform: uppercase;
    color: var(--clr-secondary);
    margin-bottom: 0.35rem;
}

.catalog-objectives ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}

.catalog-objectives li {
    font-family: var(--ff-body);
    font-size: 0.82rem;
    color: rgba(0, 44, 57, 0.75);
    padding-left: 1rem;
    position: relative;
    line-height: 1.45;
}

.catalog-objectives li::before {
    content: '›';
    position: absolute;
    left: 0;
    color: var(--clr-accent);
    font-weight: 700;
}

/* Footer */
.catalog-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 0.5rem;
    border-top: 1px solid rgba(0, 44, 57, 0.08);
    margin-top: auto;
}

.catalog-price {
    font-family: var(--ff-body);
    font-size: 0.85rem;
    color: rgba(0, 44, 57, 0.5);
}

.btn-preview {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    background: var(--clr-secondary);
    color: var(--clr-text-light);
    font-family: var(--ff-body);
    font-size: 0.83rem;
    font-weight: 700;
    padding: 0.45rem 1rem;
    border-radius: 100px;
    text-decoration: none;
    transition: background 0.2s ease, transform 0.2s ease;
}

.btn-preview:hover {
    background: var(--clr-accent);
    color: var(--clr-primary);
    transform: translateY(-1px);
}

.btn-coming-soon {
    display: inline-flex;
    align-items: center;
    background: rgba(0, 44, 57, 0.08);
    color: rgba(0, 44, 57, 0.4);
    font-family: var(--ff-body);
    font-size: 0.83rem;
    font-weight: 700;
    padding: 0.45rem 1rem;
    border-radius: 100px;
}

@media (max-width: 600px) {
    .catalog-grid { grid-template-columns: 1fr; }
}

/* ============================================================
   3. CONTACT SECTION (Ichie's two-column, ALPS-themed)
   ============================================================ */

#contact {
    background-color: var(--clr-bg);
    padding-block: var(--spacing-xl);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.4fr;
    gap: var(--spacing-xl);
    align-items: start;
}

/* Left column */
.contact-left { display: flex; flex-direction: column; gap: 0; }

.contact-overline {
    font-family: var(--ff-body);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    background: linear-gradient(to right, var(--clr-primary), var(--clr-secondary), var(--clr-accent));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: var(--spacing-sm);
}

.contact-heading {
    font-family: var(--ff-header);
    font-size: clamp(1.35rem, 2.5vw, 1.8rem);
    font-weight: var(--fw-bold);
    color: var(--clr-primary);
    line-height: 1.2;
    margin-bottom: var(--spacing-sm);
}

.contact-body {
    font-family: var(--ff-body);
    font-size: 1.05rem;
    line-height: 1.65;
    color: rgba(0, 44, 57, 0.7);
    margin-bottom: var(--spacing-md);
}

/* Right column: form box */
.contact-form-box {
    background: var(--clr-secondary);
    border-radius: 1rem;
    padding: var(--spacing-md);
}

.contact-form-stack {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.contact-form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
}

.contact-row-trio {
    grid-template-columns: 1fr 1fr 80px;
}

.contact-form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.contact-full { grid-column: 1 / -1; }

.contact-form-group label {
    font-family: var(--ff-header);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.65);
}

.contact-form-group input,
.contact-form-group textarea {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 0.5rem;
    padding: 0.7rem 0.9rem;
    color: var(--clr-text-light);
    font-family: var(--ff-body);
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s ease, background 0.2s ease;
}

.contact-form-group input::placeholder,
.contact-form-group textarea::placeholder {
    color: rgba(255, 255, 255, 0.28);
}

.contact-form-group input:focus,
.contact-form-group textarea:focus {
    border-color: var(--clr-accent);
    background: rgba(255, 255, 255, 0.12);
}

.contact-form-group textarea {
    resize: vertical;
    min-height: 96px;
}

.contact-submit-btn {
    width: 100%;
    padding: 0.9rem;
    background: var(--clr-accent);
    color: var(--clr-primary);
    font-family: var(--ff-header);
    font-weight: 700;
    font-size: 1rem;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background 0.25s ease, box-shadow 0.25s ease;
    margin-top: 0.25rem;
}

.contact-submit-btn:hover {
    background: #00d9a0;
    box-shadow: 0 0 22px rgba(0, 193, 142, 0.4);
}

.contact-success {
    text-align: center;
    padding: var(--spacing-md);
    color: var(--clr-text-light);
}

.contact-success h3 {
    font-family: var(--ff-header);
    color: var(--clr-accent);
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

@media (max-width: 900px) {
    .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
    .contact-form-row { grid-template-columns: 1fr; }
    .contact-row-trio { grid-template-columns: 1fr 1fr; }
    .contact-form-box { padding: var(--spacing-sm); }
}

/* ============================================================
   4. UDEMY-STYLE COURSE PLAYER (courses.html) - PREMIUM DARK MODE
   ============================================================ */

.player-body {
    margin: 0;
    padding: 0;
    background: #0a0b10; /* Deep, sleek dark background */
    color: var(--clr-text-light);
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

/* Topbar */
.player-topbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 72px; /* Spacious topbar */
    background: var(--clr-primary); /* ALPS Navy */
    border-bottom: 1px solid rgba(255, 255, 255, 0.08); /* Soft separator */
    display: flex;
    align-items: center;
    gap: 1.5rem;
    padding-inline: 2rem; 
    z-index: 100;
    flex-shrink: 0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.player-back {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: rgba(255, 255, 255, 0.7);
    transition: color 0.2s ease;
    flex-shrink: 0;
}

.player-back:hover { color: var(--clr-accent); }
.player-back svg { width: 1.2rem; height: 1.2rem; stroke: currentColor; }

.player-logo {
    max-height: 32px; 
    width: auto;
    opacity: 0.95;
}

.player-course-title {
    flex: 1;
    font-family: var(--ff-header);
    font-size: 1.05rem; 
    font-weight: var(--fw-bold);
    color: rgba(255, 255, 255, 0.9); 
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    text-align: center;
}

/* Right side of Topbar (Badge + Toggle) */
.player-topbar-right { 
    flex-shrink: 0;
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.player-preview-badge {
    font-family: var(--ff-body);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--clr-accent);
    background: rgba(0, 193, 142, 0.12);
    border: 1px solid rgba(0, 193, 142, 0.3);
    border-radius: 50px;
    padding: 0.35rem 1rem;
}

.sidebar-toggle {
    background: none;
    border: none;
    cursor: pointer;
    color: rgba(255, 255, 255, 0.7);
    padding: 0.5rem;
    display: flex;
    align-items: center;
    transition: color 0.2s ease, transform 0.2s ease;
}

.sidebar-toggle:hover { 
    color: var(--clr-accent); 
    transform: scale(1.05);
}
.sidebar-toggle svg { width: 1.4rem; height: 1.4rem; stroke: currentColor; }

/* Layout below topbar */
.player-layout {
    display: flex;
    height: calc(100vh - 72px);
    margin-top: 72px;
    overflow: hidden;
}

/* SIDEBAR */
.player-sidebar {
    width: 360px; /* Spacious width */
    flex-shrink: 0;
    background: #001921; /* Slightly darker than ALPS Navy to distinguish from topbar */
    border-right: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    flex-direction: column;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    overflow: hidden;
}

.player-sidebar.collapsed { width: 0; }

.sidebar-header {
    padding: 1.5rem 2rem; 
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    flex-shrink: 0;
    background: rgba(0, 0, 0, 0.15); /* Slight darkening for the header area */
}

.sidebar-heading {
    font-family: var(--ff-header);
    font-size: 0.9rem;
    font-weight: var(--fw-bold);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.6);
    margin: 0;
}

.sidebar-scroll {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 0; 
}

.sidebar-scroll::-webkit-scrollbar { width: 6px; }
.sidebar-scroll::-webkit-scrollbar-track { background: transparent; }
.sidebar-scroll::-webkit-scrollbar-thumb { background: rgba(255, 255, 255, 0.15); border-radius: 4px; }

/* Chapter group */
.sidebar-chapter { margin-bottom: 0.5rem; }

.sidebar-chapter-btn {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    padding: 1rem 2rem; 
    background: transparent;
    border: none;
    cursor: pointer;
    text-align: left;
    font-family: var(--ff-header);
    font-size: 0.95rem;
    font-weight: var(--fw-bold);
    color: rgba(255, 255, 255, 0.85);
    letter-spacing: 0.02em;
    transition: background 0.2s ease;
}

.sidebar-chapter-btn:hover { background: rgba(255, 255, 255, 0.03); }

.sidebar-chapter-chevron {
    width: 0.9em;
    height: 0.9em;
    stroke: rgba(255, 255, 255, 0.4);
    flex-shrink: 0;
    transition: transform 0.25s ease;
}

.sidebar-chapter-btn.is-open .sidebar-chapter-chevron { transform: rotate(90deg); }

.sidebar-lessons {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
}

.sidebar-lessons.is-open { max-height: 800px; }

/* Individual lesson row */
.sidebar-lesson {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.85rem 2rem 0.85rem 3rem; 
    font-family: var(--ff-body);
    font-size: 0.95rem;
    line-height: 1.4;
    color: rgba(255, 255, 255, 0.65);
    cursor: pointer;
    transition: background 0.15s ease, color 0.15s ease;
    border-left: 4px solid transparent;
}

.sidebar-lesson:hover {
    background: rgba(255, 255, 255, 0.05);
    color: #ffffff;
}

.sidebar-lesson.active {
    background: rgba(0, 193, 142, 0.1); 
    color: var(--clr-accent);
    border-left-color: var(--clr-accent);
    font-weight: 700;
}

.sidebar-lesson.locked {
    color: rgba(255, 255, 255, 0.25); 
    cursor: default;
}

.sidebar-lesson.locked:hover {
    background: transparent;
    color: rgba(255, 255, 255, 0.25);
}

/* Lock/play icon in sidebar */
.lesson-icon {
    width: 1rem;
    height: 1rem;
    flex-shrink: 0;
    stroke: currentColor;
    fill: none;
}

/* Locked chapter with overlay */
.sidebar-chapter--locked .sidebar-chapter-btn {
    opacity: 0.4;
    cursor: default;
}

/* CONTENT AREA */
.player-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: #0a0b10;
}

.player-frame-wrap {
    flex: 1;
    position: relative;
    background: #050608; /* Extremely dark background to frame the bright iframe content */
    overflow: hidden;
}

.player-frame-wrap iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

/* Placeholder */
.player-placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    text-align: center;
    padding: 2rem;
    background: #0a0b10;
}

.player-placeholder-icon {
    width: 80px;
    height: 80px;
    border: 2px dashed rgba(0, 193, 142, 0.35);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 193, 142, 0.05);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.player-placeholder-icon svg {
    width: 36px;
    height: 36px;
    stroke: var(--clr-accent);
    fill: none;
}

.player-placeholder h3 {
    font-family: var(--ff-header);
    font-size: 1.3rem;
    color: rgba(255, 255, 255, 0.9);
    margin: 0;
}

.player-placeholder p {
    font-family: var(--ff-body);
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.5);
    max-width: 350px;
    margin: 0;
}

/* Lesson info bar */
.player-lesson-info {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.25rem 2rem; 
    background: #00151c; /* Deep ALPS shade */
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.lesson-info-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.lesson-info-number {
    font-family: var(--ff-body);
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--clr-accent);
}

.lesson-info-title {
    font-family: var(--ff-header);
    font-size: 1.1rem;
    font-weight: var(--fw-bold);
    color: rgba(255, 255, 255, 0.9);
    margin: 0;
}

.lesson-info-badge {
    font-family: var(--ff-body);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.5);
    background: rgba(255, 255, 255, 0.08);
    border-radius: 4px;
    padding: 0.3rem 0.75rem;
}

/* Locked wall */
.player-locked-wall {
    position: absolute;
    inset: 0;
    background: rgba(5, 6, 8, 0.9); /* Dark frosted background */
    backdrop-filter: blur(8px); 
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 5;
}

.locked-wall-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
    text-align: center;
    padding: 3rem;
    max-width: 420px;
    background: #001e28;
    border-radius: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5); 
}

.locked-wall-icon {
    width: 64px;
    height: 64px;
    stroke: var(--clr-accent);
    fill: none;
    opacity: 0.8;
}

.locked-wall-inner h3 {
    font-family: var(--ff-header);
    font-size: 1.4rem;
    color: rgba(255, 255, 255, 0.95);
    margin: 0;
    font-weight: var(--fw-bold);
}

.locked-wall-inner p {
    font-family: var(--ff-body);
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.6);
    margin: 0;
    line-height: 1.6;
}

.locked-wall-btn {
    display: inline-flex;
    align-items: center;
    background: var(--clr-accent);
    color: var(--clr-primary);
    font-family: var(--ff-header);
    font-size: 1rem;
    font-weight: var(--fw-bold);
    text-decoration: none;
    padding: 0.8rem 2rem;
    border-radius: 50px;
    transition: background 0.2s ease, transform 0.2s ease;
    margin-top: 0.5rem;
}

.locked-wall-btn:hover {
    background: #00d9a0;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 193, 142, 0.3);
}

/* Mobile player */
@media (max-width: 768px) {
    .player-sidebar {
        position: fixed;
        top: 72px;
        left: 0;
        height: calc(100vh - 72px);
        z-index: 50;
        width: 320px; 
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        box-shadow: 5px 0 25px rgba(0, 0, 0, 0.5);
    }

    .player-sidebar.mobile-open {
        transform: translateX(0);
    }

    .player-course-title {
        display: none; 
    }
}