:root {
    --bg-main: #030712;
    --bg-surface: #0b1329;
    --bg-card: rgba(15, 23, 42, 0.75);
    --primary: #38bdf8;
    --primary-glow: #0284c7;
    --accent-purple: #818cf8;
    --accent-emerald: #34d399;
    --text-white: #ffffff;
    --text-dim: #94a3b8;
    --border-glass: rgba(255, 255, 255, 0.12);
    --border-glow: rgba(56, 189, 248, 0.5); 
    --radius-pill: 9999px;
    --radius-lg: 28px;
    --radius-md: 16px;
    --font-main: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: var(--font-main);
}

html {
    scroll-behavior: smooth;
    -webkit-tap-highlight-color: transparent;
}

body {
    background-color: var(--bg-main);
    color: var(--text-white);
    line-height: 1.6;
    overflow-x: hidden;
    padding-bottom: 0px;
}

#heroCanvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
}

header {
    background: rgba(3, 7, 18, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    border-bottom: 1px solid var(--border-glass);
    padding: 1rem 8%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: -1px;
    color: var(--text-white);
    display: flex;
    align-items: center;
    gap: 10px;
    z-index: 1002;
}

.logo-badge {
    background: linear-gradient(135deg, var(--primary), var(--accent-purple));
    width: 12px;
    height: 12px;
    border-radius: 50%;
    box-shadow: 0 0 15px var(--primary);
}

.logo span {
    background: linear-gradient(135deg, #38bdf8, #818cf8);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-desktop {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-desktop a.nav-link {
    color: var(--text-dim);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: color 0.3s ease;
}

.nav-desktop a.nav-link:hover {
    color: var(--text-white);
}

.notes-count-badge {
    background: var(--primary);
    color: var(--bg-main);
    font-weight: 800;
    font-size: 0.75rem;
    padding: 2px 7px;
    border-radius: 10px;
}

.btn-header {
    background: linear-gradient(135deg, rgba(56, 189, 248, 0.1), rgba(129, 140, 248, 0.1));
    border: 1px solid var(--border-glow);
    color: var(--text-white);
    padding: 0.7rem 1.8rem;
    border-radius: var(--radius-pill);
    font-weight: 700;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s ease;
    backdrop-filter: blur(8px);
}

.btn-header:hover {
    background: var(--primary);
    color: var(--bg-main);
    box-shadow: 0 0 25px rgba(56, 189, 248, 0.6);
}

.hamburger-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1005;
    flex-direction: column;
    gap: 6px;
}

.hamburger-btn span {
    display: block;
    width: 26px;
    height: 2.5px;
    background-color: var(--text-white);
    border-radius: 2px;
    transition: all 0.3s ease-in-out;
}

.hamburger-btn.active span:nth-child(1) {
    transform: translateY(8.5px) rotate(45deg);
}

.hamburger-btn.active span:nth-child(2) {
    opacity: 0;
}

.hamburger-btn.active span:nth-child(3) {
    transform: translateY(-8.5px) rotate(-45deg);
}

.mobile-drawer {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 320px;
    height: 100vh;
    background: rgba(11, 19, 41, 0.98);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border-left: 1px solid var(--border-glass);
    z-index: 1003;
    display: flex;
    flex-direction: column;
    padding: 5rem 2rem 2rem;
    gap: 1.2rem;
    transition: right 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: -10px 0 40px rgba(0, 0, 0, 0.8);
}

.mobile-drawer.open {
    right: 0;
}

.drawer-close-btn {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--border-glass);
    color: var(--text-white);
    font-size: 1.3rem;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.drawer-close-btn:active {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(0.95);
}

.mobile-drawer a {
    color: var(--text-white);
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 600;
    padding: 0.9rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    display: flex;
    align-items: center;
    gap: 12px;
}

.mobile-drawer a.highlight {
    color: var(--primary);
}

.drawer-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(3, 7, 18, 0.75);
    backdrop-filter: blur(4px);
    z-index: 1002;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}

.drawer-overlay.open {
    opacity: 1;
    pointer-events: auto;
}

.notes-drawer {
    position: fixed;
    top: 0;
    right: -420px;
    width: 380px;
    height: 100vh;
    background: rgba(11, 19, 41, 0.98);
    backdrop-filter: blur(20px);
    border-left: 1px solid var(--border-glow);
    z-index: 1005;
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    transition: right 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: -10px 0 40px rgba(0, 0, 0, 0.8);
}

.notes-drawer.open {
    right: 0;
}

.notes-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--border-glass);
    padding-bottom: 0.8rem;
}

.notes-close-btn {
    background: none;
    border: none;
    color: var(--text-white);
    font-size: 1.8rem;
    cursor: pointer;
}

.notes-section-selector {
    margin-bottom: 1rem;
}

.custom-select-notes {
    width: 100%;
    background: rgba(15, 23, 42, 0.9);
    border: 1px solid var(--border-glow);
    color: var(--text-white);
    padding: 0.6rem 0.8rem;
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    outline: none;
}

#notesContent {
    width: 100%;
    flex: 1;
    background: rgba(15, 23, 42, 0.8);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    padding: 1rem;
    color: var(--text-white);
    font-family: var(--font-main);
    font-size: 0.95rem;
    resize: none;
    outline: none;
}

#notesContent:focus {
    border-color: var(--primary);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.2);
}

.section-title-wrapper {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
    flex-wrap: wrap;
}

.btn-inline-note {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-glass);
    color: var(--text-dim);
    padding: 0.3rem 0.8rem;
    border-radius: var(--radius-pill);
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.3s ease;
}

.btn-inline-note:hover {
    background: rgba(56, 189, 248, 0.15);
    border-color: var(--primary);
    color: var(--text-white);
}

.btn-inline-note.has-note {
    background: rgba(52, 211, 153, 0.15);
    border-color: var(--accent-emerald);
    color: var(--accent-emerald);
    font-weight: 700;
    box-shadow: 0 0 12px rgba(52, 211, 153, 0.3);
}

.btn-inline-note.has-note .note-icon::after {
    content: ' ✓';
}

.mobile-bottom-bar {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 65px;
    background: rgba(11, 19, 41, 0.95);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-top: 1px solid var(--border-glass);
    z-index: 999;
    justify-content: space-around;
    align-items: center;
}

.mobile-bottom-bar a {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.75rem;
    font-weight: 600;
}

.mobile-bottom-bar a.active, .mobile-bottom-bar a:hover {
    color: var(--primary);
}

.mobile-bottom-bar a .icon {
    font-size: 1.2rem;
}

.hero {
    position: relative;
    padding: 8rem 8% 4rem;
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    z-index: 2;
}

.hero-container {
    max-width: 1100px;
    margin: 0 auto;
    width: 100%;
}

.hero-tag {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: rgba(56, 189, 248, 0.08);
    border: 1px solid var(--border-glow);
    padding: 0.5rem 1.4rem;
    border-radius: var(--radius-pill);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 1.5rem;
    box-shadow: 0 0 20px rgba(56, 189, 248, 0.15);
}

.hero-title {
    font-size: clamp(2.2rem, 5.5vw, 4.5rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -1.5px;
    margin-bottom: 1.5rem;
}

.hero-title span.glow-text {
    background: linear-gradient(135deg, #38bdf8 0%, #818cf8 50%, #34d399 100%);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-dim);
    max-width: 820px;
    margin: 0 auto 2.8rem;
    font-weight: 400;
}

.hero-cta-group {
    display: flex;
    gap: 1.2rem;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
}

.btn-primary-glow {
    background: linear-gradient(135deg, #0284c7 0%, #38bdf8 100%);
    color: #ffffff;
    padding: 1.1rem 2.8rem;
    border-radius: var(--radius-pill);
    font-size: 1.05rem;
    font-weight: 800;
    text-decoration: none;
    box-shadow: 0 0 35px rgba(56, 189, 248, 0.4);
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary-glow:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 0 50px rgba(56, 189, 248, 0.7);
}

.btn-glass {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgb(172, 172, 172);
    color: var(--text-white);
    padding: 1.1rem 2.4rem;
    border-radius: var(--radius-pill);
    font-size: 1.05rem;
    font-weight: 700;
    text-decoration: none;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    cursor: pointer;
}

.btn-glass:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: var(--text-white);
}

.metrics-bar {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 3.5rem auto 0;
    padding: 2rem 2.5rem;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(12px);
    box-shadow: 0 0 30px rgba(2, 132, 199, 0.15);
}

.metric-item h3 {
    font-size: 2.2rem;
    font-weight: 800;
    color: var(--primary);
    letter-spacing: -1px;
}

.metric-item p {
    color: var(--text-dim);
    font-size: 0.95rem;
    font-weight: 600;
}

.section-padding {
    padding: 4rem 6% 5rem;
    max-width: 1400px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

.section-header {
    text-align: center;
    margin-bottom: 3.5rem;
}

.section-header h2 {
    font-size: clamp(1.8rem, 3.8vw, 3rem);
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 0.8rem;
}

.section-header p {
    color: var(--text-dim);
    font-size: 1.15rem;
    margin: 0 auto;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2.5rem;
    max-width: 1200px;
    margin: 0 auto;
}

.glass-card {
    background: rgba(15, 23, 42, 0.8);
    border: 2px solid var(--primary-glow);
    border-radius: var(--radius-lg);
    padding: 2.5rem 2.2rem;
    position: relative;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    backdrop-filter: blur(16px);
    box-shadow: 0 0 30px rgba(2, 132, 199, 0.15);
}

.glass-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -150%;
    width: 200%;
    height: 200%;
    background: linear-gradient(
        60deg, 
        transparent 30%, 
        rgba(255, 255, 255, 0.18) 50%, 
        transparent 70%
    );
    transform: rotate(25deg);
    transition: all 0.8s ease;
    pointer-events: none;
}

.glass-card:hover::before {
    left: 100%;
}

.glass-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 0 50px rgba(2, 132, 199, 0.35);
}

.card-header {
    display: flex;
    align-items: center;
    gap: 1.2rem;
    margin-bottom: 1.2rem;
}

.card-icon-tech {
    width: 60px;
    height: 60px;
    min-width: 60px;
    background: linear-gradient(135deg, rgba(56, 189, 248, 0.15), rgba(129, 140, 248, 0.15));
    border: 1px solid var(--border-glow);
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    box-shadow: 0 0 20px rgba(56, 189, 248, 0.2);
}

.glass-card h3 {
    font-size: 1.45rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    line-height: 1.25;
}

.glass-card p {
    color: var(--text-dim);
    font-size: 1.02rem;
    line-height: 1.7;
}

.pricing-section {
    padding: 5rem 6%;
    background: linear-gradient(180deg, var(--bg-main) 0%, #081026 100%);
    border-top: 1px solid var(--border-glass);
    position: relative;
}

.pricing-box {
    max-width: 950px;
    margin: 0 auto;
    background: rgba(15, 23, 42, 0.8);
    border: 2px solid var(--primary-glow);
    border-radius: 32px;
    padding: 4rem 3rem;
    text-align: center;
    box-shadow: 0 0 80px rgba(2, 132, 199, 0.25);
    backdrop-filter: blur(20px);
}

.pricing-badge {
    background: linear-gradient(135deg, var(--accent-emerald), #059669);
    color: #000000;
    font-weight: 900;
    padding: 0.5rem 1.8rem;
    border-radius: var(--radius-pill);
    font-size: 0.85rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    display: inline-block;
    margin-bottom: 1.5rem;
}

.pricing-box h2 {
    font-size: clamp(2rem, 4vw, 2.8rem);
    font-weight: 800;
    letter-spacing: -1.5px;
    margin-bottom: 1rem;
}

.pricing-box p.subtitle {
    color: var(--text-dim);
    font-size: 1.2rem;
    margin-bottom: 3rem;
}

.pricing-features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    text-align: left;
    margin-bottom: 3.5rem;
}

.pricing-feature-item {
    background: rgba(15, 23, 42, 0.7);
    border: 1px solid rgba(56, 189, 248, 0.6);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.2);
    padding: 1.1rem 1.4rem;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1rem;
    font-weight: 600;
    position: relative;
    overflow: hidden;
    transition: all 0.4s ease;
    backdrop-filter: blur(8px);
}

.pricing-feature-item::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -150%;
    width: 200%;
    height: 200%;
    background: linear-gradient(
        60deg, 
        transparent 30%, 
        rgba(255, 255, 255, 0.22) 50%, 
        transparent 70%
    );
    transform: rotate(25deg);
    transition: all 0.7s ease;
    pointer-events: none;
}

.pricing-feature-item:hover::before {
    left: 100%;
}

.pricing-feature-item:hover {
    border-color: rgba(56, 189, 248, 1);
    box-shadow: 0 0 30px rgba(56, 189, 248, 0.45);
    transform: translateY(-3px);
}

.pricing-feature-item span {
    color: var(--accent-emerald);
    font-size: 1.3rem;
}

footer {
    text-align: center;
    padding: 1.5rem 2rem;
    border-top: 1px solid var(--border-glass);
    color: var(--text-dim);
    font-size: 0.85rem;
    background: rgba(3, 7, 18, 0.95);
}

.progress-container {
    width: 100%;
    background: rgba(255, 255, 255, 0.08);
    height: 8px;
    border-radius: var(--radius-pill);
    overflow: hidden;
    margin: 1rem 0;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent-emerald));
    border-radius: var(--radius-pill);
    box-shadow: 0 0 12px var(--primary);
    transition: width 0.5s ease;
}

.student-dashboard {
    padding-top: 6rem;
    min-height: 100vh;
    display: flex;
    gap: 2rem;
    max-width: 1600px;
    margin: 0 auto;
    padding-left: 2rem;
    padding-right: 2rem;
}

.course-sidebar {
    width: 320px;
    min-width: 320px;
    background: rgba(11, 19, 41, 0.85);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    backdrop-filter: blur(16px);
    height: calc(100vh - 8rem);
    position: sticky;
    top: 7rem;
    overflow-y: auto;
}

.course-sidebar h3 {
    font-size: 1.1rem;
    color: var(--text-white);
    margin-bottom: 1.2rem;
    padding-bottom: 0.8rem;
    border-bottom: 1px solid var(--border-glass);
}

.module-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.module-item {
    border-radius: var(--radius-md);
    background: rgba(15, 23, 42, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: all 0.3s ease;
}

.module-item.active {
    border-color: var(--border-glow);
    background: rgba(56, 189, 248, 0.1);
}

.module-title {
    padding: 0.8rem 1rem;
    font-size: 0.92rem;
    font-weight: 700;
    color: var(--text-white);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.topic-list {
    list-style: none;
    padding: 0.5rem 1rem 1rem;
}

.topic-link {
    display: block;
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.85rem;
    padding: 0.4rem 0;
    transition: all 0.3s ease;
}

.topic-link:hover {
    color: var(--text-white);
}

.topic-link.active {
    color: var(--primary) !important;
    font-weight: 700;
}

.reader-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
    margin-bottom: 3rem;
}

.module-card-block {
    background: rgba(15, 23, 42, 0.9);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    backdrop-filter: blur(16px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4), 0 0 20px rgba(2, 132, 199, 0.15);
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.module-card-block:hover {
    border-color: var(--primary);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.5), 0 0 25px rgba(56, 189, 248, 0.25);
}

.reader-header {
    margin-bottom: 2rem;
    padding-bottom: 1.2rem;
    border-bottom: 1px solid var(--border-glass);
}

.reader-category {
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 0.5rem;
}

.reader-title {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.reading-content section,
.reading-content div.annotatable-section {
    scroll-margin-top: 8rem;
    margin-bottom: 2rem;
}

.reading-content h1, 
.reading-content h2, 
.reading-content h3 {
    color: var(--text-white);
    margin-top: 2rem;
    margin-bottom: 1rem;
    font-weight: 800;
}

.reading-content h2 {
    font-size: 1.6rem;
    border-left: 4px solid var(--primary);
    padding-left: 1rem;
}

.reading-content h3 {
    font-size: 1.25rem;
    color: var(--accent-purple);
}

.reading-content p {
    color: #cbd5e1;
    font-size: 1.05rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

pre {
    background: #020617 !important;
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    overflow-x: auto;
    margin: 1.5rem 0;
    box-shadow: 0 0 25px rgba(0, 0, 0, 0.5);
}

code {
    font-family: 'Fira Code', 'Courier New', Courier, monospace;
    color: var(--accent-emerald);
    font-size: 0.95rem;
}

.callout-box {
    background: rgba(56, 189, 248, 0.08);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    margin: 1.5rem 0;
    position: relative;
}

.callout-box.tip {
    background: rgba(52, 211, 153, 0.08);
    border-color: var(--accent-emerald);
}

.callout-title {
    font-weight: 800;
    color: var(--text-white);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.table-responsive {
    overflow-x: auto;
    margin: 2rem 0;
}

.custom-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    background: rgba(11, 19, 41, 0.6);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.custom-table th {
    background: rgba(56, 189, 248, 0.15);
    color: var(--text-white);
    padding: 1rem;
    font-weight: 700;
    border-bottom: 1px solid var(--border-glass);
}

.custom-table td {
    padding: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--text-dim);
}

.custom-table tr:hover td {
    background: rgba(255, 255, 255, 0.03);
    color: var(--text-white);
}

.module-item.locked {
    opacity: 0.45;
    background: rgba(15, 23, 42, 0.2);
    border-color: rgba(255, 255, 255, 0.03);
    cursor: not-allowed;
    user-select: none;
}

.module-item.locked .module-title {
    cursor: not-allowed;
    color: var(--text-dim);
}

.status-icon {
    font-size: 0.9rem;
}

.lesson-footer {
    margin-top: 3.5rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-glass);
}

.quiz-container {
    background: rgba(11, 19, 41, 0.8);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-md);
    padding: 2rem;
    margin-bottom: 2.5rem;
}

.quiz-container h3 {
    font-size: 1.2rem;
    color: var(--text-white);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0.8rem 1rem;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    margin-bottom: 0.8rem;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.95rem;
}

.quiz-option:hover {
    border-color: var(--primary);
    background: rgba(56, 189, 248, 0.08);
}

.quiz-option input[type="radio"] {
    accent-color: var(--primary);
}

.lesson-nav-buttons {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

@media (max-width: 992px) {
    .nav-desktop { display: none; }
    .hamburger-btn { display: flex; }
    .mobile-bottom-bar { display: flex; }
    body { padding-bottom: 65px; }

    header { padding: 0.9rem 6%; }

    .hero {
        padding-top: 7rem;
        padding-bottom: 2.5rem;
        min-height: auto;
    }

    .hero-tag {
        font-size: 0.75rem;
        padding: 0.4rem 1rem;
    }

    .hero-subtitle {
        font-size: 1.05rem;
        margin-bottom: 2rem;
    }

    .metrics-bar {
        grid-template-columns: 1fr;
        gap: 1.2rem;
        padding: 1.5rem;
    }

    .metric-item h3 { font-size: 1.8rem; }

    .cards-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .glass-card {
        padding: 1.8rem 1.4rem;
    }

    .card-icon-tech {
        width: 50px;
        height: 50px;
        min-width: 50px;
        font-size: 1.5rem;
    }

    .glass-card h3 {
        font-size: 1.25rem;
    }

    .pricing-box {
        padding: 2.5rem 1.5rem;
        border-radius: 24px;
    }

    .pricing-features-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .pricing-feature-item {
        font-size: 0.92rem;
        padding: 0.9rem 1.1rem;
    }

    .btn-primary-glow, .btn-glass {
        width: 100%;
        text-align: center;
        padding: 1rem 1.5rem;
        min-height: 52px;
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .student-dashboard {
        flex-direction: column;
        padding-left: 1rem;
        padding-right: 1rem;
    }

    .course-sidebar {
        width: 100%;
        min-width: 100%;
        height: auto;
        position: relative;
        top: 0;
    }

    .reader-container {
        padding: 0;
    }

    .module-card-block {
        padding: 1.5rem;
    }

    .notes-drawer {
        width: 100%;
        right: -100%;
    }
}

/* =========================================================================
   BOTÃO FLUTUANTE DE TELA CHEIA (DESIGN REFORÇADO DE ALTA VISIBILIDADE)
   ========================================================================= */
.btn-floating-fullscreen {
    position: fixed;
    bottom: 28px;
    right: 28px;
    width: 54px;
    height: 54px;
    border-radius: 50%;
    background: linear-gradient(135deg, #0284c7 0%, #38bdf8 100%);
    border: 2px solid rgba(255, 255, 255, 0.4);
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 0 25px rgba(56, 189, 248, 0.6), 0 8px 20px rgba(0, 0, 0, 0.4);
    z-index: 999;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.btn-floating-fullscreen svg {
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
}

.btn-floating-fullscreen:hover {
    transform: scale(1.15);
    background: linear-gradient(135deg, #38bdf8 0%, #818cf8 100%);
    border-color: #ffffff;
    box-shadow: 0 0 35px rgba(56, 189, 248, 0.9), 0 10px 25px rgba(0, 0, 0, 0.5);
}

.btn-floating-fullscreen:active {
    transform: scale(0.92);
}