html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    font-family: var(--font-sans);
    background-color: var(--bg-main);
    color: var(--text-main);
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin: 0;
}

a { text-decoration: none; color: inherit; }
button { font-family: inherit; }
.no-underline { text-decoration: none; }
.text-inherit { color: inherit; }

/* =========================================
   2. LANDING PAGE STYLES
   ========================================= */
.landing-container { width: 100%; margin-inline: auto; padding-inline: 1.5rem; max-width: 100%; }
@media (min-width: 640px) { .landing-container { max-width: 640px; } }
@media (min-width: 768px) { .landing-container { max-width: 768px; } }
@media (min-width: 1024px) { .landing-container { max-width: 1024px; } }
@media (min-width: 1280px) { .landing-container { max-width: 1280px; } }

nav.landing-nav { position: fixed; top: 0; width: 100%; z-index: 40; transition: all 300ms ease; }
nav.landing-nav::before { content: ""; position: absolute; inset: 0; background-color: color-mix(in srgb, var(--bg-main) 90%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border-color); z-index: -1; }
nav.landing-nav .container { height: 5rem; display: flex; align-items: center; justify-content: space-between; position: relative; z-index: 10; }
.landing-nav__logo { display: flex; align-items: center; gap: 0.5ch; cursor: pointer; }
.landing-nav__links { display: none; }
@media (min-width: 768px) { .landing-nav__links { display: flex; gap: 2ch; font-size: 0.875rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.1em; } .landing-nav__links a:hover { color: var(--accent-primary); } }
.landing-nav__cta { background-color: var(--accent-primary); color: var(--bg-main); padding: 0.5rem 1.5rem; border-radius: 9999px; font-weight: 900; text-transform: uppercase; letter-spacing: 0.05em; transition: all 300ms ease; }
.landing-nav__cta:hover { transform: scale(1.05); }

header.landing-hero { position: relative; min-height: 100vh; display: flex; align-items: center; justify-content: center; padding-top: 5rem; overflow: hidden; }
.landing-hero .bg-layer { position: absolute; inset: 0; z-index: 0; }
.landing-hero .bg-layer img { width: 100%; height: 100%; object-fit: cover; filter: grayscale(20%); }
.landing-hero .bg-layer::after { content: ""; position: absolute; inset: 0; z-index: 10; background-color: var(--bg-main); mix-blend-mode: multiply; opacity: 0.5; }
.landing-hero .hero-content { position: relative; z-index: 20; text-align: center; display: flex; flex-direction: column; align-items: center; padding-inline: 1.5rem; }
.landing-hero h1 { font-family: var(--font-display); font-size: 3.75rem; line-height: 0.9; margin-bottom: 1.5rem; }
@media (min-width: 768px) { .landing-hero h1 { font-size: 8rem; } }
.landing-hero .highlight { color: var(--accent-primary); }
.landing-hero p.subtitle { font-size: 1.25rem; color: var(--text-muted); max-width: 42rem; margin-bottom: 2.5rem; }
.landing-hero .cta-group { display: flex; flex-direction: column; gap: 1rem; width: 100%; justify-content: center; }
@media (min-width: 768px) { .landing-hero .cta-group { flex-direction: row; } }
.landing-hero .btn-primary { padding: 1.25rem 2.5rem; background-color: var(--accent-primary); color: var(--bg-main); font-weight: 900; font-size: 1.25rem; text-transform: uppercase; border-radius: 0.75rem; transition: transform 300ms ease; }
.landing-hero .btn-primary:hover { transform: scale(1.05); }
.landing-hero .btn-secondary { padding: 1.25rem 2.5rem; background: var(--bg-card); backdrop-filter: blur(12px); color: var(--text-main); font-weight: 700; font-size: 1.125rem; text-transform: uppercase; border-radius: 0.75rem; border: 1px solid var(--border-color); }

/* =========================================
   3. DASHBOARD STYLES
   ========================================= */
.dashboard-layout { display: flex; flex-direction: row; height: 100vh; width: 100vw; background-color: var(--bg-main); color: var(--text-main); overflow: hidden; }

.sidebar { width: 5rem; height: auto; background-color: var(--ocean-900); border-right: 1px solid var(--border-color); display: flex; flex-direction: column; align-items: center; padding-block: 1rem 2rem; flex-shrink: 0; z-index: 70; }
@media (min-width: 1024px) { .sidebar { width: 6rem; } }
.sidebar__brand { margin-bottom: 3rem; padding-left: 0.5rem; color: var(--accent-primary); cursor: pointer; display: flex; align-items: center; justify-content: center; }
.sidebar__brand:hover { }
.sidebar__brand .icon-large { font-size: 2.5rem; display: block; }
.sidebar__nav { flex: 1; width: 100%; display: flex; flex-direction: column; align-items: center; gap: 2rem; }
.sidebar .nav-item { width: 100%; height: 3rem; border-radius: 0; display: flex; align-items: center; justify-content: center; color: var(--text-muted); background: transparent; border: none; cursor: pointer; transition: all 0.2s ease; text-decoration: none; margin: 0; padding: 0; }
.sidebar .nav-item:hover { color: var(--accent-primary); background: transparent; }
.sidebar .nav-item.active .material-symbols-outlined { background: linear-gradient(to right, var(--accent-primary), #3b82f6); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.sidebar .material-symbols-outlined { font-size: 1.5rem; }
.sidebar__user { margin-top: auto; }
.sidebar .user-avatar { width: 2.5rem; height: 2.5rem; border-radius: 50%; border: 2px solid var(--border-color); padding: 2px; overflow: hidden; cursor: pointer; display: block; }
.sidebar .user-avatar:hover { border-color: var(--accent-primary); }
.sidebar .user-avatar img { width: 100%; height: 100%; border-radius: 50%; object-fit: cover; }

.main-content { flex: 1; display: flex; flex-direction: column; min-width: 0; height: 100%; position: relative; overflow: hidden; background-color: var(--bg-main); }

.topbar .page-title {
    font-family: var(--font-display);
    font-size: 1.875rem;
    letter-spacing: 0.025em;
    text-transform: uppercase;
    margin: 0;
    font-weight: 600;
    position: relative;
    padding-bottom: 4px;
    background: linear-gradient(to right, var(--accent-primary), #3b82f6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.topbar .page-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--admin-teal);
    transition: width 0.3s ease;
}

.topbar .page-title:hover {
    filter: brightness(1.2);
}

.topbar .page-title:hover::after {
    width: 100%; /* Full width underline on hover */
}

.topbar__actions { display: flex; align-items: center; gap: 1.5rem; }
.search-bar { display: none; }
@media (min-width: 768px) { .search-bar { display: flex; align-items: center; background-color: var(--bg-card); padding: 0.5rem 1rem; border-radius: 9999px; border: 1px solid var(--border-color); width: 16rem; } .search-bar input { background: transparent; border: none; color: var(--text-main); margin-left: 0.5rem; outline: none; width: 100%; } }
.xp-pill { display: flex; align-items: center; gap: 0.75rem; background-color: var(--bg-card); padding: 0.375rem 1rem; border-radius: 9999px; border: 1px solid var(--border-color); }
.xp-pill .xp-count { display: flex; align-items: center; gap: 0.25rem; color: var(--text-main); font-family: var(--font-display); font-size: 1.125rem; }
.xp-pill .material-symbols-outlined { color: var(--accent-primary); font-size: 1.125rem; }
.xp-pill .separator { width: 1px; height: 1rem; background-color: var(--border-color); }
.xp-pill .level { font-size: 0.75rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; }

.shaka-icon {
    width: 30px;
    height: 30px;
    display: inline-block;
    vertical-align: middle;
    color: var(--avant-teal);
}

/* Hover effect */
.xp-count:hover .shaka-icon {
    color: var(--avant-teal);
}

.content-scroll { flex: 1; overflow-y: auto; padding: 0; position: relative; width: 100%; }
@media (min-width: 768px) { .content-scroll { padding: 0; } }

.hero-banner { position: relative; height: 400px; border-radius: 1.5rem; overflow: hidden; margin-bottom: 3rem; border: 1px solid var(--border-color); box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25); }
.hero-banner .bg-image { position: absolute; inset: 0; }
.hero-banner .bg-image img { width: 100%; height: 100%; object-fit: cover; opacity: 0.6; }
.hero-banner .overlay { position: absolute; inset: 0; background: linear-gradient(to right, var(--bg-main), rgba(5, 11, 20, 0.6), transparent); }
.hero-content { position: absolute; inset: 0; padding: 2.5rem; display: flex; flex-direction: column; justify-content: center; max-width: 42rem; }
.hero-content .tags { display: flex; gap: 0.75rem; margin-bottom: 1rem; }
.hero-content .tag { padding: 0.25rem 0.75rem; font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; border-radius: 0.125rem; }
.hero-content .tag--primary { background-color: var(--accent-primary); color: var(--bg-main); }
.hero-content .tag--glass { background-color: color-mix(in srgb, var(--text-main) 10%, transparent); color: var(--text-main); backdrop-filter: blur(4px); }
.hero-content h2 { font-family: var(--font-display); font-size: 3.75rem; line-height: 0.9; margin-bottom: 0.5rem; text-transform: uppercase; }
.hero-content .highlight { background: linear-gradient(to right, var(--accent-primary), #3b82f6); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-content p { font-size: 1.125rem; color: var(--text-muted); font-weight: 300; line-height: 1.6; margin-bottom: 2rem; max-width: 32rem; }
.hero-content .actions { display: flex; gap: 1rem; }
.hero-content .btn-primary { padding: 1rem 2rem; background-color: var(--text-main); color: var(--bg-main); font-family: var(--font-display); font-size: 1.25rem; text-transform: uppercase; border-radius: 0.125rem; border: none; cursor: pointer; display: inline-flex; align-items: center; gap: 0.5rem; }
.hero-content .btn-secondary { padding: 1rem 2rem; background: transparent; color: var(--text-main); border: 1px solid var(--border-color); font-family: var(--font-display); font-size: 1.25rem; text-transform: uppercase; border-radius: 0.125rem; cursor: pointer; }
.hero-progress { width: 100%; max-width: 24rem; margin-bottom: 1.5rem; }
.hero-progress__bar { height: 6px; background: color-mix(in oklch, var(--text-main) 15%, transparent); border-radius: 3px; overflow: hidden; }
.hero-progress__fill { height: 100%; background: var(--accent-primary); border-radius: 3px; transition: width 0.4s ease; }

.filters { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem; margin-bottom: 2rem; border-bottom: 1px solid var(--border-color); padding-bottom: 1.5rem; }
.filters .filter-btn { padding: 0.5rem 1.5rem; border-radius: 9999px; font-size: 0.875rem; font-weight: 700; border: 1px solid var(--border-color); background-color: var(--bg-surface); color: var(--text-muted); cursor: pointer; transition: all 0.15s ease; }
.filters .filter-btn:hover { background-color: color-mix(in srgb, var(--text-main) 10%, transparent); color: var(--text-main); }
.filters .filter-btn.active { background-color: var(--accent-primary); color: var(--bg-main); border-color: var(--accent-primary); }

.course-grid { display: grid; grid-template-columns: 1fr; gap: 1.5rem; margin-bottom: 3rem; }
@media (min-width: 768px) { .course-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .course-grid { grid-template-columns: repeat(3, 1fr); } }
@media (min-width: 1280px) { .course-grid { grid-template-columns: repeat(4, 1fr); } }
.course-card { background: rgba(255,255,255,0.03); backdrop-filter: blur(12px); border-radius: 1rem; overflow: hidden; border: 1px solid rgba(255,255,255,0.05); transition: all 0.3s ease; cursor: pointer; position: relative; text-decoration: none; }
.course-card:hover { transform: translateY(-4px); background: rgba(255,255,255,0.08); }
.course-card.teal { border-color: rgba(100, 255, 218, 0.3); }
.course-card.teal:hover { border-color: #64ffda; box-shadow: 0 0 20px rgba(100, 255, 218, 0.15); }
.course-card.blue { border-color: rgba(0, 180, 216, 0.3); }
.course-card.blue:hover { border-color: #00b4d8; box-shadow: 0 0 20px rgba(0, 180, 216, 0.15); }
.course-card.yellow { border-color: rgba(255, 204, 0, 0.2); }
.course-card.yellow:hover { border-color: #ffcc00; box-shadow: 0 0 20px rgba(255, 204, 0, 0.15); }
.course-card.pink { border-color: rgba(247, 37, 133, 0.2); }
.course-card.pink:hover { border-color: #f72585; box-shadow: 0 0 20px rgba(247, 37, 133, 0.15); }
.course-card .card-image { height: 10rem; position: relative; overflow: hidden; }
.course-card .card-image img { width: 100%; height: 100%; object-fit: cover; opacity: 0.6; filter: grayscale(100%); transition: all 0.5s ease; }
.course-card:hover .card-image img { opacity: 1; filter: grayscale(0%); transform: scale(1.05); }
.course-card .card-content { padding: 1rem; }
.course-card .card-content h3 { font-family: var(--font-display); font-size: 1.35rem; margin-bottom: 0.25rem; text-transform: uppercase; color: white; line-height: 1.1; }
.course-card .card-content p { font-size: 0.8rem; color: #8d99ae; line-height: 1.4; margin: 0.25rem 0 0.75rem; }
.course-card .meta { display: flex; justify-content: space-between; align-items: center; font-size: 0.75rem; font-weight: 700; color: var(--text-muted); padding-top: 0.5rem; border-top: 1px solid rgba(255,255,255,0.05); }
.course-card .meta .xp { color: var(--accent-primary); }

/* =========================================
   4. COURSE PAGE & TUTORIAL STYLES
   ========================================= */
.course-page-layout { max-width: 1200px; margin: 0 auto; width: 100%; }
.glass-soul { background: color-mix(in srgb, var(--bg-surface) 40%, transparent); backdrop-filter: blur(12px); border: 1px solid var(--border-color); }
.flex { display: flex; } .flex-col { flex-direction: column; } .items-center { align-items: center; } .items-start { align-items: flex-start; } .justify-between { justify-content: space-between; } .justify-center { justify-content: center; }
.gap-1 { gap: 0.25rem; } .gap-2 { gap: 0.5rem; } .gap-3 { gap: 0.75rem; } .gap-4 { gap: 1rem; } .gap-6 { gap: 1.5rem; } .gap-8 { gap: 2rem; } .gap-10 { gap: 2.5rem; }
.p-3 { padding: 0.75rem; } .p-4 { padding: 1rem; } .p-6 { padding: 1.5rem; }
.mb-1 { margin-bottom: 0.25rem; } .mb-2 { margin-bottom: 0.5rem; } .mb-3 { margin-bottom: 0.75rem; } .mb-4 { margin-bottom: 1rem; } .mb-6 { margin-bottom: 1.5rem; } .mb-8 { margin-bottom: 2rem; } .mb-12 { margin-bottom: 3rem; }
.mt-8 { margin-top: 2rem; } .mt-12 { margin-top: 3rem; }
.rounded { border-radius: 0.25rem; } .rounded-lg { border-radius: 0.5rem; } .rounded-xl { border-radius: 0.75rem; } .rounded-full { border-radius: 9999px; }
.uppercase { text-transform: uppercase; } .font-display { font-family: var(--font-display); } .font-bold { font-weight: 700; } .font-light { font-weight: 300; }
.text-xs { font-size: 0.75rem; } .text-sm { font-size: 0.875rem; } .text-base { font-size: 1rem; } .text-lg { font-size: 1.125rem; } .text-xl { font-size: 1.25rem; } .text-2xl { font-size: 1.5rem; } .text-3xl { font-size: 1.875rem; } .text-4xl { font-size: 2.25rem; } .text-5xl { font-size: 3rem; }
.tracking-widest { letter-spacing: 0.1em; } .tracking-wide { letter-spacing: 0.025em; }
.text-white { color: var(--text-main); } .text-avant-gray { color: var(--text-muted); } .text-avant-teal { color: var(--accent-primary); } .text-ocean-950 { color: var(--ocean-950); }
.bg-ocean-800 { background-color: var(--ocean-800); } .bg-ocean-900 { background-color: var(--ocean-900); } .bg-ocean-950 { background-color: var(--ocean-950); } .bg-avant-teal { background-color: var(--accent-primary); } .bg-black { background-color: #000; } .bg-transparent { background-color: transparent; }
.border { border-width: 1px; border-style: solid; } .border-transparent { border-color: transparent; } .border-white\/5 { border-color: color-mix(in srgb, var(--text-main) 5%, transparent); } .border-white\/10 { border-color: var(--border-color); } .border-white\/20 { border-color: color-mix(in srgb, var(--text-main) 20%, transparent); } .border-avant-teal { border-color: var(--accent-primary); } .border-b { border-bottom-width: 1px; } .border-l-2 { border-left-width: 2px; }
.w-full { width: 100%; } .h-full { height: 100%; } .w-5 { width: 1.25rem; } .h-5 { height: 1.25rem; } .w-8 { width: 2rem; } .h-8 { height: 2rem; } .w-20 { width: 5rem; } .h-20 { height: 5rem; }
.object-cover { object-fit: cover; } .absolute { position: absolute; } .fixed { position: fixed; } .inset-0 { inset: 0; } .relative { position: relative; } .sticky { position: sticky; } .top-6 { top: 1.5rem; }
.grid { display: grid; } .grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.flex-1 { flex: 1; } .flex-shrink-0 { flex-shrink: 0; }
.cursor-pointer { cursor: pointer; } .cursor-not-allowed { cursor: not-allowed; }
.opacity-60 { opacity: 0.6; } .opacity-80 { opacity: 0.8; }
.transition-colors { transition: background-color 0.2s, color 0.2s, border-color 0.2s; } .transition-all { transition: all 0.2s; }
.hover\:bg-white\/5:hover { background-color: color-mix(in srgb, var(--text-main) 5%, transparent); } .hover\:bg-white\/10:hover { background-color: color-mix(in srgb, var(--text-main) 10%, transparent); } .hover\:bg-white\/20:hover { background-color: color-mix(in srgb, var(--text-main) 20%, transparent); } .hover\:text-white:hover { color: var(--text-main); } .hover\:scale-110:hover { transform: scale(1.1); }
@media (min-width: 768px) { .md\:flex-row { flex-direction: row; } .md\:p-12 { padding: 3rem; } .md\:w-1\/3 { width: 33.333333%; } .md\:text-5xl { font-size: 3rem; } }
@media (min-width: 1024px) { .lg\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); } .lg\:col-span-2 { grid-column: span 2 / span 2; } .lg\:flex-row { flex-direction: row; } .lg\:w-80 { width: 20rem; } }

/* Tutorial View Specific */
.tutorial-wrapper { display: flex; height: calc(100vh - 5rem); overflow: hidden; position: relative; background-color: var(--bg-main); }
.course-sidebar { width: 20rem; background-color: var(--bg-surface); border-right: 1px solid var(--border-color); display: flex; flex-direction: column; flex-shrink: 0; transition: transform 0.3s ease; z-index: 40; }
@media (max-width: 1024px) { .course-sidebar { position: absolute; top: 0; left: 0; bottom: 0; transform: translateX(-100%); } .course-sidebar.open { transform: translateX(0); } }
.tutorial-content { flex: 1; overflow-y: auto; position: relative; background-color: var(--bg-main); }
.content-container { max-width: 64rem; margin: 0 auto; padding: 2rem; }
.custom-checkbox { position: relative; width: 1.25rem; height: 1.25rem; cursor: pointer; flex-shrink: 0; }
.custom-checkbox input { opacity: 0; width: 0; height: 0; position: absolute; }
.checkmark { position: absolute; top: 0; left: 0; height: 1.25rem; width: 1.25rem; border: 1px solid var(--text-muted); border-radius: 0.25rem; background-color: transparent; transition: all 0.2s; display: flex; align-items: center; justify-content: center; }
.custom-checkbox input:checked ~ .checkmark { background-color: var(--accent-primary); border-color: var(--accent-primary); }
.checkmark span { font-size: 0.875rem; color: var(--bg-main); opacity: 0; transform: scale(0.5); transition: all 0.2s; }
.custom-checkbox input:checked ~ .checkmark span { opacity: 1; transform: scale(1); }
.aspect-video { aspect-ratio: 16 / 9; }
.custom-scrollbar::-webkit-scrollbar { width: 4px; }
.custom-scrollbar::-webkit-scrollbar-track { background: transparent; }
.custom-scrollbar::-webkit-scrollbar-thumb { background: color-mix(in srgb, var(--text-main) 10%, transparent); border-radius: 4px; }
.custom-scrollbar::-webkit-scrollbar-thumb:hover { background: color-mix(in srgb, var(--text-main) 20%, transparent); }
.sidebar-header { padding: 1.5rem; border-bottom: 1px solid var(--border-color); }
.back-link { display: flex; align-items: center; gap: 0.5rem; color: var(--text-muted); font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 1rem; text-decoration: none; transition: color 0.2s; }
.back-link:hover { color: var(--text-main); }
.back-link span { font-size: 1rem; }
.course-title { font-family: var(--font-display); font-size: 1.5rem; color: var(--text-main); margin-bottom: 1rem; line-height: 1.1; text-transform: uppercase; }
.progress-container { margin-top: auto; }
.progress-bar { height: 0.25rem; background-color: rgba(255,255,255,0.1); border-radius: 9999px; overflow: hidden; margin-bottom: 0.5rem; }
.progress-bar .fill { height: 100%; background-color: var(--accent-primary); box-shadow: 0 0 10px var(--accent-primary); border-radius: 9999px; }
.progress-fill { height: 100%; background-color: var(--accent-primary); box-shadow: 0 0 10px var(--accent-primary); }
.progress-meta { display: flex; justify-content: space-between; font-size: 0.625rem; font-weight: 700; text-transform: uppercase; color: var(--text-muted); }
.module-list { flex: 1; overflow-y: auto; padding: 0.5rem; }
.module-item { display: flex; align-items: center; gap: 0.75rem; padding: 0.75rem; border-radius: 0.5rem; transition: background-color 0.2s; position: relative; }
.module-item:hover { background-color: color-mix(in srgb, var(--text-main) 5%, transparent); }
.module-item.active { background-color: color-mix(in srgb, var(--text-main) 8%, transparent); }
.module-item:hover .module-title { color: var(--text-main); }
.module-item.active .module-title { color: var(--text-main); font-weight: 700; }
.active-indicator { width: 0.375rem; height: 0.375rem; background-color: var(--accent-primary); border-radius: 50%; box-shadow: 0 0 5px var(--accent-primary); }
.video-container { margin-bottom: 2.5rem; }
.video-wrapper { position: relative; width: 100%; border-radius: 0.75rem; overflow: hidden; border: 1px solid var(--border-color); box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5); background-color: black; }
.video-placeholder { width: 100%; height: 100%; object-fit: cover; opacity: 0.8; transition: opacity 0.3s; }
.video-wrapper:hover .video-placeholder { opacity: 0.6; }
.play-btn { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); width: 5rem; height: 5rem; border-radius: 50%; background-color: var(--accent-primary); border: none; color: var(--bg-main); display: flex; align-items: center; justify-content: center; cursor: pointer; box-shadow: 0 0 30px rgba(45, 212, 191, 0.4); transition: transform 0.2s; }
.play-btn:hover { transform: translate(-50%, -50%) scale(1.1); }
.play-btn span { font-size: 3rem; }
.lesson-content { margin-bottom: 3rem; }
.lesson-title { font-family: var(--font-display); font-size: 3rem; color: var(--text-main); text-transform: uppercase; margin-bottom: 1.5rem; line-height: 1; }
.prose { font-size: 1.125rem; line-height: 1.75; color: var(--text-muted); font-weight: 300; }
.prose p { margin-bottom: 1.5rem; }
.prose strong { color: var(--text-main); font-weight: 600; }
.prose ul { list-style: disc; padding-left: 1.5rem; margin-bottom: 1.5rem; }
.prose li { margin-bottom: 0.5rem; }
.prose h3 { color: var(--text-main); font-size: 1.5rem; margin-top: 2rem; margin-bottom: 1rem; }
.lesson-footer { border-top: 1px solid var(--border-color); padding-top: 2rem; margin-top: 2rem; }
.nav-buttons { display: flex; justify-content: space-between; gap: 1rem; }
.nav-btn { display: inline-flex; align-items: center; gap: 0.5rem; padding: 0.75rem 1.5rem; border-radius: 0.25rem; font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; text-decoration: none; transition: all 0.2s; }
.nav-btn.prev { color: var(--text-muted); border: 1px solid var(--border-color); }
.nav-btn.prev:hover { background-color: color-mix(in srgb, var(--text-main) 5%, transparent); color: var(--text-main); }
.nav-btn.next, .nav-btn.finish { background-color: var(--accent-primary); color: var(--bg-main); box-shadow: 0 0 15px rgba(45, 212, 191, 0.2); }
.nav-btn.next:hover, .nav-btn.finish:hover { background-color: var(--text-main); }
.mobile-toggle { position: absolute; top: 1rem; left: 1rem; z-index: 50; background-color: var(--bg-surface); color: var(--text-main); border: 1px solid var(--border-color); padding: 0.5rem; border-radius: 0.25rem; cursor: pointer; display: none; }
@media (max-width: 1024px) { .mobile-toggle { display: block; } }
.sidebar-overlay { position: fixed; inset: 0; background-color: rgba(0,0,0,0.5); z-index: 30; }
.hidden { display: none; }
.spacer { height: 5rem; }

/* =========================================
   5. AUTH STYLES
   ========================================= */
.auth-layout { min-height: 100vh; display: flex; align-items: center; justify-content: center; background-color: var(--bg-main); background-image: linear-gradient(to bottom right, var(--ocean-950), color-mix(in srgb, var(--ocean-900) 80%, black)); position: relative; overflow: hidden; }
.auth-layout::before { content: ""; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%; background: radial-gradient(circle at center, var(--avant-teal-dim) 0%, transparent 50%); opacity: 0.4; animation: auth-pulse 10s ease-in-out infinite alternate; pointer-events: none; }
@keyframes auth-pulse { 0% { transform: scale(1); opacity: 0.3; } 100% { transform: scale(1.1); opacity: 0.5; } }
.auth-card { position: relative; width: 100%; max-width: 40ch; padding: 3rem; background: color-mix(in srgb, var(--bg-surface) 40%, transparent); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border: 1px solid var(--border-color); border-radius: 1.5rem; box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(255, 255, 255, 0.05) inset; display: flex; flex-direction: column; gap: 2rem; z-index: 10; }
.auth-header { text-align: center; margin-bottom: 1rem; }
.auth-header__logo { display: block; margin: 0 auto 1.5rem; color: var(--accent-primary); transition: transform 0.3s ease; }
.auth-header__logo:hover { transform: scale(1.05); }
.auth-header h1 { font-family: var(--font-display); font-size: 2.5rem; font-weight: 400; color: var(--text-main); letter-spacing: 0.02em; margin-bottom: 0.5rem; }
.auth-header p { color: var(--text-muted); font-size: 0.875rem; font-family: var(--font-sans); }
.auth-form { display: flex; flex-direction: column; gap: 1.5rem; }
.form-group { display: flex; flex-direction: column; gap: 0.5rem; position: relative; }
.form-group label { font-family: var(--font-sans); font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-muted); transition: color 0.2s ease; }
.form-input { width: 100%; background: color-mix(in srgb, var(--bg-main) 60%, transparent); border: none; border-bottom: 2px solid var(--border-color); border-radius: 0.25rem 0.25rem 0 0; padding: 0.75rem 1rem; color: var(--text-main); font-family: var(--font-sans); font-size: 1rem; transition: all 0.2s ease; }
.form-input:focus { outline: none; background: color-mix(in srgb, var(--bg-main) 90%, transparent); border-bottom-color: var(--accent-primary); box-shadow: 0 4px 12px rgba(45, 212, 191, 0.1); }
.form-input:focus + label { color: var(--accent-primary); }
.form-input::placeholder { color: color-mix(in srgb, var(--text-muted) 30%, transparent); }
.auth-actions { display: flex; flex-direction: column; gap: 1rem; margin-top: 1rem; }
.btn-auth { display: inline-flex; align-items: center; justify-content: center; width: 100%; padding: 1rem; background-color: var(--accent-primary); color: var(--bg-main); font-family: var(--font-display); font-size: 1.125rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; border: none; border-radius: 0.25rem; cursor: pointer; transition: all 0.2s ease; text-decoration: none; box-shadow: 0 0 20px rgba(45, 212, 191, 0.2); }
.btn-auth:hover { transform: translateY(-2px); box-shadow: 0 0 30px rgba(45, 212, 191, 0.4); background-color: white; }
.auth-links { display: flex; justify-content: space-between; font-size: 0.75rem; margin-top: 0.5rem; }
.link-subtle { color: var(--text-muted); text-decoration: none; transition: color 0.2s ease; border-bottom: 1px solid transparent; }
.link-subtle:hover { color: var(--accent-primary); border-bottom-color: var(--accent-primary); }