:root {
    --background: #0b1120;
    --surface: #111827;
    --surface-light: #1f2937;
    --text: #f8fafc;
    --muted: #94a3b8;
    --primary: #38bdf8;
    --primary-dark: #0284c7;
    --success: #34d399;
    --border: #263244;
    --max-width: 1680px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--background);
    color: var(--text);
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.6;
}

a {
    color: inherit;
    text-decoration: none;
}

.container {
    width: min(calc(100% - 4rem), var(--max-width));
    margin-inline: auto;
}

.site-header {
    background: rgb(11 17 32 / 90%);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 10;
    backdrop-filter: blur(12px);
}

.navbar {
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    color: var(--primary);
    font-size: 1.25rem;
    font-weight: 700;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.nav-links a {
    color: var(--muted);
}

.nav-links a:hover {
    color: var(--text);
}

.hero {
    padding: 8rem 0 7rem;
    background:
        radial-gradient(circle at top right, #075985 0, transparent 35%),
        var(--background);
}

.hero-content {
    max-width: var(--max-width);
}

.eyebrow {
    color: var(--primary);
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.hero h1 {
    max-width: 850px;
    margin: 0.75rem 0 1.25rem;
    font-size: clamp(2.5rem, 6vw, 4.75rem);
    line-height: 1.05;
}

.hero-description {
    max-width: 650px;
    color: var(--muted);
    font-size: 1.2rem;
}

.button {
    display: inline-block;
    margin-top: 1.25rem;
    padding: 0.85rem 1.25rem;
    background: var(--primary);
    color: #082f49;
    border-radius: 0.5rem;
    font-weight: 700;
}

.button:hover {
    background: #7dd3fc;
}

.paths-section {
    padding: 6rem 0;
}

.section-heading {
    margin-bottom: 2rem;
}

.section-heading h2 {
    margin: 0;
    font-size: 2.25rem;
}

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

.path-card {
    min-height: 300px;
    padding: 1.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.path-card:hover {
    border-color: var(--primary-dark);
    transform: translateY(-3px);
    transition: 0.2s ease;
}

.path-card h3 {
    margin-bottom: 0.5rem;
    font-size: 1.4rem;
}

.path-card p {
    color: var(--muted);
}

.status {
    display: inline-block;
    padding: 0.25rem 0.65rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 700;
}

.available {
    background: rgb(52 211 153 / 15%);
    color: var(--success);
}

.coming-soon {
    background: var(--surface-light);
    color: var(--muted);
}

.card-link {
    color: var(--primary);
    font-weight: 700;
}

.card-link.disabled {
    color: var(--muted);
}

.site-footer {
    padding: 2rem 0;
    color: var(--muted);
    border-top: 1px solid var(--border);
}

@media (max-width: 800px) {
    .path-grid {
        grid-template-columns: 1fr;
    }

    .nav-links {
        gap: 0.75rem;
    }

    .hero {
        padding: 6rem 0 5rem;
    }
}

.course-count {
    margin-top: 1.5rem;
    color: var(--text) !important;
    font-size: 0.9rem;
    font-weight: 700;
}

.empty-state {
    padding: 3rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    text-align: center;
}

.empty-state h3 {
    margin-top: 0;
}

.empty-state p {
    color: var(--muted);
}

.path-hero {
    padding: 6rem 0 4rem;
    background:
        radial-gradient(circle at top right, #075985 0, transparent 35%),
        var(--background);
}

.path-hero h1 {
    margin: 0.75rem 0 1rem;
    font-size: clamp(2.5rem, 5vw, 4rem);
}

.path-hero p {
    max-width: 700px;
    color: var(--muted);
    font-size: 1.1rem;
}

.back-link {
    display: inline-block;
    margin-bottom: 2rem;
    color: var(--muted);
}

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

.courses-section {
    padding: 5rem 0;
}

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

.course-card {
    padding: 1.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    display: grid;
    grid-template-columns: 60px 1fr auto;
    align-items: center;
    gap: 1.5rem;
}

.course-card:hover {
    border-color: var(--primary-dark);
}

.course-number {
    color: var(--primary);
    font-size: 1.25rem;
    font-weight: 700;
}

.course-information h3 {
    margin: 0.5rem 0;
}

.course-information p {
    margin: 0;
    color: var(--muted);
}

.course-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    color: var(--muted);
    font-size: 0.8rem;
    text-transform: uppercase;
}

@media (max-width: 700px) {
    .course-card {
        grid-template-columns: 1fr;
    }

    .course-number {
        display: none;
    }
}


.course-hero {
    padding: 5rem 0;
    background:
        radial-gradient(circle at top right, #075985 0, transparent 35%),
        var(--background);
}

.course-heading {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 320px;
    align-items: start;
    gap: 4rem;
}

.course-heading h1 {
    margin: 0.75rem 0 1rem;
    font-size: clamp(2.5rem, 5vw, 4rem);
    line-height: 1.1;
}

.course-description {
    max-width: 700px;
    color: var(--muted);
    font-size: 1.1rem;
}

.course-summary {
    padding: 1.5rem;
    background: rgb(17 24 39 / 85%);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.difficulty-badge {
    display: inline-block;
    padding: 0.3rem 0.7rem;
    background: rgb(56 189 248 / 15%);
    color: var(--primary);
    border-radius: 999px;
    font-size: 0.8rem;
    font-weight: 700;
}

.course-summary dl {
    margin: 1.5rem 0 0;
}

.course-summary dl div {
    padding: 0.8rem 0;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    gap: 1rem;
}

.course-summary dl div:last-child {
    border-bottom: 0;
}

.course-summary dt {
    color: var(--muted);
}

.course-summary dd {
    margin: 0;
    font-weight: 700;
}

.curriculum-section {
    padding: 5rem 0;
}

.module-list {
    display: grid;
    gap: 1.5rem;
}

.module-card {
    overflow: hidden;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.module-header {
    padding: 1.5rem;
    display: grid;
    grid-template-columns: 100px 1fr auto;
    align-items: center;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
}

.module-position {
    color: var(--primary);
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
}

.module-header h3 {
    margin: 0;
    font-size: 1.25rem;
}

.module-header p {
    margin: 0.4rem 0 0;
    color: var(--muted);
}

.module-total {
    color: var(--muted);
    font-size: 0.9rem;
}

.lesson-list {
    display: grid;
}

.lesson-row {
    min-height: 78px;
    padding: 1rem 1.5rem;
    display: grid;
    grid-template-columns: 30px 44px 1fr auto;
    align-items: center;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
}

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

.lesson-row:hover {
    background: var(--surface-light);
}

.lesson-number {
    color: var(--muted);
    font-size: 0.8rem;
}

.lesson-icon {
    width: 40px;
    height: 40px;
    background: rgb(56 189 248 / 10%);
    color: var(--primary);
    border-radius: 50%;
    display: grid;
    place-items: center;
}

.lesson-information h4 {
    margin: 0;
}

.lesson-information span {
    color: var(--muted);
    font-size: 0.8rem;
}

.lesson-duration {
    color: var(--muted);
    font-size: 0.9rem;
}

.module-empty {
    padding: 1.5rem;
    color: var(--muted);
}

@media (max-width: 800px) {
    .course-heading {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .module-header {
        grid-template-columns: 1fr;
    }

    .lesson-row {
        grid-template-columns: 40px 1fr auto;
    }

    .lesson-number {
        display: none;
    }
}



.lesson-page {
    min-height: 80vh;
    padding: 3rem 0 5rem;
}

.lesson-container {
    max-width: none;
}

.lesson-breadcrumbs {
    margin-bottom: 3rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    color: var(--muted);
    font-size: 0.9rem;
}

.lesson-breadcrumbs a:hover {
    color: var(--primary);
}

.lesson-header {
    margin-bottom: 2rem;
}

.lesson-header h1 {
    margin: 1rem 0;
    font-size: clamp(2.25rem, 5vw, 3.75rem);
    line-height: 1.1;
}

.lesson-labels {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.8rem;
    color: var(--muted);
    font-size: 0.85rem;
}

.lesson-type-badge {
    padding: 0.3rem 0.7rem;
    background: rgb(56 189 248 / 15%);
    color: var(--primary);
    border-radius: 999px;
    font-weight: 700;
}

.video-container {
    position: relative;
    overflow: hidden;
    width: 100%;
    padding-top: 56.25%;
    background: #000;
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.video-container iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

.lesson-content {
    margin-top: 2rem;
    padding: 2rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    color: #dbe5f1;
    font-size: 1.05rem;
    line-height: 1.8;
}

.lesson-content p:first-child {
    margin-top: 0;
}

.lesson-content p:last-child {
    margin-bottom: 0;
}

.article-content {
    margin-top: 0;
}

.lab-content {
    padding: 2rem;
    background: rgb(52 211 153 / 5%);
    border: 1px solid rgb(52 211 153 / 35%);
    border-radius: 0.75rem;
}

.lab-content .lesson-content {
    padding: 0;
    background: transparent;
    border: 0;
}

.lab-heading {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.lab-heading h2,
.lab-heading p {
    margin: 0;
}

.lab-icon {
    width: 50px;
    height: 50px;
    background: rgb(52 211 153 / 15%);
    color: var(--success);
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-size: 1.25rem;
}

.lesson-navigation {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 1rem;
}

.lesson-navigation > div:last-child {
    text-align: right;
}

.lesson-navigation-link {
    display: inline-flex;
    flex-direction: column;
    gap: 0.25rem;
}

.lesson-navigation-link span {
    color: var(--muted);
    font-size: 0.8rem;
}

.lesson-navigation-link strong {
    color: var(--primary);
}

.course-return {
    color: var(--muted);
    font-size: 0.9rem;
}

.course-return:hover {
    color: var(--text);
}

@media (max-width: 700px) {
    .lesson-navigation {
        grid-template-columns: 1fr;
    }

    .lesson-navigation > div:last-child {
        text-align: left;
    }

    .course-return {
        grid-row: 3;
    }

    .lesson-content,
    .lab-content {
        padding: 1.25rem;
    }
}


.auth-section {
    min-height: calc(100vh - 145px);
    padding: 5rem 1rem;
    display: grid;
    place-items: center;
}

.auth-card {
    width: min(100%, 520px);
    padding: 2rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.auth-heading {
    margin-bottom: 2rem;
}

.auth-heading h1 {
    margin: 0.5rem 0;
    font-size: 2rem;
}

.auth-heading p:last-child {
    color: var(--muted);
}

.auth-form {
    display: grid;
    gap: 1.25rem;
}

.form-group {
    display: grid;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 700;
}

.form-group input {
    width: 100%;
    padding: 0.85rem 1rem;
    background: var(--background);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font: inherit;
}

.form-group input:focus {
    border-color: var(--primary);
    outline: 2px solid rgb(56 189 248 / 20%);
}

.field-help {
    color: var(--muted);
    font-size: 0.8rem;
}

.field-help ul {
    margin: 0.5rem 0 0;
    padding-left: 1.25rem;
}

.field-error {
    margin: 0;
    color: #f87171;
    font-size: 0.85rem;
}

.form-errors,
.message {
    margin-bottom: 1rem;
    padding: 1rem;
    border-radius: 0.5rem;
}

.form-errors {
    background: rgb(248 113 113 / 10%);
    color: #fca5a5;
    border: 1px solid rgb(248 113 113 / 30%);
}

.message.success {
    background: rgb(52 211 153 / 10%);
    color: var(--success);
    border: 1px solid rgb(52 211 153 / 30%);
}

.auth-button {
    width: 100%;
    border: 0;
    cursor: pointer;
    font: inherit;
}

.auth-switch {
    margin: 1.5rem 0 0;
    color: var(--muted);
    text-align: center;
}

.auth-switch a {
    color: var(--primary);
    font-weight: 700;
}

.logout-form {
    margin: 0;
}

.nav-button {
    padding: 0;
    background: none;
    color: var(--muted);
    border: 0;
    cursor: pointer;
    font: inherit;
}

.nav-button:hover {
    color: var(--text);
}

.nav-signup {
    padding: 0.45rem 0.8rem;
    background: var(--primary);
    color: #082f49 !important;
    border-radius: 0.4rem;
    font-weight: 700;
}

.dashboard-hero {
    padding: 5rem 0 3rem;
    background:
        radial-gradient(circle at top right, #075985 0, transparent 35%),
        var(--background);
}

.dashboard-hero h1 {
    margin: 0.5rem 0;
    font-size: clamp(2.25rem, 5vw, 3.75rem);
}

.dashboard-hero p:last-child {
    color: var(--muted);
    font-size: 1.1rem;
}

.dashboard-section {
    padding: 3rem 0 6rem;
}

.dashboard-stats {
    margin-bottom: 4rem;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
}

.stat-card {
    padding: 1.25rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.stat-card span {
    display: block;
    color: var(--muted);
    font-size: 0.85rem;
}

.stat-card strong {
    display: block;
    margin-top: 0.4rem;
    font-size: 2rem;
}

.dashboard-heading {
    margin-bottom: 2rem;
}

.dashboard-heading h2 {
    margin: 0;
    font-size: 2rem;
}

@media (max-width: 800px) {
    .dashboard-stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .navbar {
        align-items: flex-start;
        gap: 1rem;
        padding-block: 1rem;
    }

    .nav-links {
        flex-wrap: wrap;
        justify-content: flex-end;
    }
}

@media (max-width: 500px) {
    .dashboard-stats {
        grid-template-columns: 1fr;
    }

    .auth-card {
        padding: 1.25rem;
    }
}

.lab-launch-panel {
    margin-top: 2rem;
    padding: 1.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
}

.lab-launch-panel p {
    color: var(--muted);
}

.danger-button {
    background: #ef4444;
    color: white;
    border: 0;
    cursor: pointer;
}

.terminal-card { margin-top: 1.5rem; overflow: hidden; background: #07111f; border: 1px solid #263b55; border-radius: 14px; box-shadow: 0 24px 70px rgb(0 0 0 / 35%); }
.terminal-toolbar, .terminal-footer { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: .8rem 1rem; background: #0d1a2c; }
.terminal-toolbar { border-bottom: 1px solid #263b55; }
.terminal-title, .terminal-actions { display: flex; align-items: center; gap: .8rem; }
.terminal-title strong, .terminal-title small { display: block; line-height: 1.3; }
.terminal-title small, .terminal-footer { color: #8496ad; font-size: .75rem; }
.terminal-dots { display: flex; gap: 5px; }
.terminal-dots i { width: 10px; height: 10px; background: #fb7185; border-radius: 50%; }
.terminal-dots i:nth-child(2) { background: #fbbf24; }
.terminal-dots i:nth-child(3) { background: #34d399; }
.terminal-state { padding: .3rem .55rem; color: #fbbf24; background: rgb(251 191 36 / 10%); border-radius: 999px; font-size: .75rem; font-weight: 700; }
.terminal-state i { display: inline-block; width: 7px; height: 7px; margin-right: 4px; background: currentColor; border-radius: 50%; }
.terminal-state.connected { color: #34d399; background: rgb(52 211 153 / 10%); }
.terminal-state.disconnected { color: #fb7185; background: rgb(251 113 133 / 10%); }
.terminal-timer { color: #a8b8cc; font: 700 .75rem monospace; }
.terminal-stop, .terminal-reconnect { padding: .4rem .65rem; color: #fff; background: #b91c1c; border: 1px solid #ef4444; border-radius: 6px; cursor: pointer; font: 700 .75rem inherit; }
.terminal-reconnect { color: #bae6fd; background: #0c4a6e; border-color: #0284c7; }
.terminal-actions form { margin: 0; }
.terminal-screen { height: clamp(480px, 58vh, 760px); padding: 12px 8px; text-align: left; }
.terminal-screen .xterm { height: 100%; }
.terminal-footer { border-top: 1px solid #263b55; }

@media (max-width: 700px) {
    .terminal-toolbar, .terminal-footer { align-items: flex-start; flex-direction: column; }
    .terminal-actions { width: 100%; flex-wrap: wrap; }
    .terminal-screen { height: 360px; }
}

.lab-workspace-grid {
    display: grid;
    grid-template-columns: minmax(0, 3fr) minmax(320px, 1fr);
    gap: 1.5rem;
    align-items: stretch;
    margin-top: 1.5rem;
}

.lab-workspace-grid .terminal-card {
    min-width: 0;
    margin-top: 0;
}

.lab-task-panel {
    display: flex;
    flex-direction: column;
    min-width: 0;
    padding: 1.4rem;
    background: linear-gradient(180deg, #142033 0%, #0f1929 100%);
    border: 1px solid #2b3b51;
    border-radius: 14px;
    box-shadow: 0 24px 70px rgb(0 0 0 / 25%);
}

.lab-task-heading {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #2b3b51;
}

.lab-task-heading .eyebrow {
    margin: 0 0 0.15rem;
    font-size: 0.7rem;
}

.lab-task-heading h3 {
    margin: 0;
    font-size: 1.1rem;
    line-height: 1.3;
}

.lab-task-icon {
    display: grid;
    flex: 0 0 38px;
    width: 38px;
    height: 38px;
    place-items: center;
    color: #082f49;
    background: var(--primary);
    border-radius: 10px;
    font-weight: 900;
}

.lab-task-description {
    flex: 1;
    padding: 1rem 0;
    color: #cbd5e1;
    font-size: 0.92rem;
}

.lab-task-description p:first-child { margin-top: 0; }
.lab-task-description p:last-child { margin-bottom: 0; }

.lab-complete-area {
    padding-top: 1rem;
    border-top: 1px solid #2b3b51;
}

.lab-complete-area p {
    margin: 0 0 0.65rem;
    color: var(--muted);
    font-size: 0.8rem;
}

.lab-complete-button {
    display: flex;
    width: 100%;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    padding: 0.75rem 1rem;
    color: #052e26;
    background: var(--success);
    border: 0;
    border-radius: 8px;
    cursor: pointer;
    font: inherit;
    font-weight: 800;
}

.lab-complete-button:hover { background: #6ee7b7; }

@media (max-width: 900px) {
    .container { width: min(calc(100% - 2rem), var(--max-width)); }
    .lab-workspace-grid { grid-template-columns: 1fr; }
    .lab-task-panel { min-height: 280px; }
    .terminal-screen { height: 480px; }
}

@media (max-width: 500px) {
    .container { width: min(calc(100% - 1rem), var(--max-width)); }
    .lab-content { padding: 1rem; }
    .terminal-screen { height: 400px; }
}