/* === CSS Custom Properties === */
:root {
    --primary-blue: #2563eb;
    --dark-blue: #1e3a5f;
    --secondary-blue: #1e40af;
    --accent-green: #10b981;
    --langguard-green: #00e676;
    --white: #ffffff;
    --dark-text: #111827;
    --body-text: #374151;
    --muted-text: #6b7280;
    --light-bg: #f9fafb;
    --blue-tint-bg: #eef3ff;
    --border-color: #e5e7eb;
    --font-stack: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --max-width: 1120px;
    --nav-height: 64px;
}

/* === Reset & Base === */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
}

body {
    font-family: var(--font-stack);
    color: var(--body-text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--primary-blue);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* === Container === */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* === Section Titles === */
.section-title {
    font-size: 2rem;
    color: var(--dark-text);
    text-align: center;
    margin-bottom: 8px;
    font-weight: 700;
}

.section-subtitle {
    text-align: center;
    color: var(--muted-text);
    font-size: 1.1rem;
    margin-bottom: 48px;
}

/* === Buttons === */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
    cursor: pointer;
    border: none;
}

.btn:hover {
    text-decoration: none;
    transform: translateY(-1px);
}

.btn-primary {
    background: var(--primary-blue);
    color: var(--white);
}

.btn-primary:hover {
    background: var(--secondary-blue);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--white);
    border: 2px solid rgba(255, 255, 255, 0.7);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--white);
}

.btn-secondary {
    background: var(--light-bg);
    color: var(--dark-text);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--white);
    border-color: var(--primary-blue);
    color: var(--primary-blue);
}

.btn-langguard {
    background: var(--langguard-green);
    color: #111;
}

.btn-langguard:hover {
    background: #00c864;
    box-shadow: 0 4px 12px rgba(0, 230, 118, 0.3);
}

/* ============================================ */
/* Section 1: Sticky Navigation                 */
/* ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    z-index: 1000;
    background: transparent;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.nav.scrolled {
    background: var(--dark-blue);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--white);
    text-decoration: none;
    font-weight: 700;
    font-size: 1.15rem;
}

.nav-brand:hover {
    text-decoration: none;
}

.nav-logo {
    width: 36px;
    height: 36px;
    border-radius: 50%;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-link {
    color: rgba(255, 255, 255, 0.85);
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    transition: color 0.2s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--white);
    text-decoration: none;
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--white);
    border-radius: 1px;
}

.nav-github {
    color: rgba(255, 255, 255, 0.85);
    transition: color 0.2s ease;
}

.nav-github:hover {
    color: var(--white);
}

.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-hamburger span {
    width: 24px;
    height: 2px;
    background: var(--white);
    border-radius: 1px;
    transition: all 0.3s ease;
}

/* ============================================ */
/* Section 2: Hero                              */
/* ============================================ */
.hero {
    background: linear-gradient(135deg, var(--dark-blue) 0%, var(--primary-blue) 100%);
    padding: 160px 24px 100px;
    text-align: center;
    color: var(--white);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-container {
    max-width: 700px;
    margin: 0 auto;
}

.hero-mascot {
    width: 180px;
    height: 180px;
    margin: 0 auto 24px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    padding: 8px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 12px;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 16px;
    font-weight: 400;
}

.hero-pitch {
    font-size: 1.15rem;
    opacity: 0.8;
    margin-bottom: 36px;
    line-height: 1.6;
}

.hero-ctas {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 48px;
    flex-wrap: wrap;
}

.hero-powered {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    opacity: 0.7;
    font-size: 0.9rem;
}

.hero-langguard-logo {
    height: 28px;
    display: inline-block;
}

/* ============================================ */
/* Section 3: About                             */
/* ============================================ */
.about {
    padding: 80px 24px;
    background: var(--white);
}

.about .section-title {
    margin-bottom: 32px;
}

.about-text {
    max-width: 780px;
    margin: 0 auto 20px;
    font-size: 1.1rem;
    line-height: 1.8;
    text-align: center;
    color: var(--body-text);
}

/* ============================================ */
/* Section 4: Features                          */
/* ============================================ */
.features {
    padding: 80px 24px;
    background: var(--light-bg);
}

.features .section-title {
    margin-bottom: 48px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--white);
    border-radius: 12px;
    padding: 32px 24px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.feature-icon {
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
}

.feature-card h3 {
    font-size: 1.15rem;
    color: var(--dark-text);
    margin-bottom: 10px;
    font-weight: 600;
}

.feature-card p {
    font-size: 0.95rem;
    color: var(--muted-text);
    line-height: 1.6;
}

/* ============================================ */
/* Section 5: Platforms                         */
/* ============================================ */
.platforms {
    padding: 80px 24px;
    background: var(--white);
}

.platforms-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 32px;
}

.platform-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--body-text);
    transition: transform 0.2s ease;
    min-width: 90px;
}

.platform-item:hover {
    transform: scale(1.08);
    text-decoration: none;
    color: var(--dark-text);
}

.platform-icon {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--light-bg);
    border: 1px solid var(--border-color);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.platform-item:hover .platform-icon {
    border-color: var(--platform-color, var(--primary-blue));
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

.platform-item span {
    font-size: 0.85rem;
    font-weight: 500;
    text-align: center;
}

/* ============================================ */
/* Section 6: Screenshots                       */
/* ============================================ */
.screenshots {
    padding: 80px 24px;
    background: var(--blue-tint-bg);
}

.screenshot-tabs {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 32px;
    flex-wrap: wrap;
}

.screenshot-tab {
    padding: 8px 20px;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    background: var(--white);
    color: var(--muted-text);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
}

.screenshot-tab:hover {
    border-color: var(--primary-blue);
    color: var(--primary-blue);
}

.screenshot-tab.active {
    background: var(--primary-blue);
    color: var(--white);
    border-color: var(--primary-blue);
}

.screenshot-panel {
    display: none;
    max-width: 960px;
    margin: 0 auto;
}

.screenshot-panel.active {
    display: block;
}

/* Browser Frame Mockup */
.browser-frame {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12), 0 2px 8px rgba(0, 0, 0, 0.06);
    background: #fff;
}

.browser-bar {
    background: #e8eaed;
    padding: 8px 12px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.browser-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}

.browser-dot.red { background: #ff5f57; }
.browser-dot.yellow { background: #febc2e; }
.browser-dot.green { background: #28c840; }

.browser-frame img {
    width: 100%;
    display: block;
}

.screenshot-caption {
    text-align: center;
    margin-top: 16px;
    font-size: 0.95rem;
    color: var(--muted-text);
}

/* ============================================ */
/* Section 7: Getting Started                   */
/* ============================================ */
.getting-started {
    padding: 80px 24px;
    background: var(--white);
}

.steps {
    max-width: 700px;
    margin: 0 auto;
}

.step {
    display: flex;
    gap: 24px;
    margin-bottom: 40px;
    align-items: flex-start;
}

.step-number {
    width: 48px;
    height: 48px;
    min-width: 48px;
    border-radius: 50%;
    background: var(--primary-blue);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
}

.step-content {
    flex: 1;
}

.step-content h3 {
    font-size: 1.2rem;
    color: var(--dark-text);
    margin-bottom: 12px;
    font-weight: 600;
}

.step-text {
    color: var(--body-text);
    line-height: 1.6;
}

pre {
    background: #1e293b;
    border-radius: 8px;
    overflow-x: auto;
}

code {
    display: block;
    padding: 16px 20px;
    font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', Consolas, monospace;
    font-size: 0.88rem;
    line-height: 1.7;
    color: #e2e8f0;
}

.code-comment {
    color: #64748b;
}

.code-keyword {
    color: #c084fc;
}

.code-string {
    color: #86efac;
}

.code-literal {
    color: #fbbf24;
}

.steps-footer {
    max-width: 700px;
    margin: 40px auto 0;
    text-align: center;
}

.steps-footer p {
    margin-bottom: 16px;
    color: var(--muted-text);
}

.steps-footer pre {
    text-align: left;
    margin-bottom: 24px;
}

/* ============================================ */
/* Section 8: Plugins                           */
/* ============================================ */
.plugins {
    padding: 80px 24px;
    background: var(--light-bg);
}

.plugin-list {
    max-width: 760px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.plugin-card {
    background: var(--white);
    border-radius: 10px;
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: box-shadow 0.2s ease;
}

.plugin-card:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.plugin-header {
    width: 100%;
    padding: 16px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    font-size: 1rem;
    text-align: left;
}

.plugin-header-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.plugin-name {
    font-weight: 600;
    color: var(--dark-text);
}

.plugin-chevron {
    color: var(--muted-text);
    font-size: 0.9rem;
    transition: transform 0.2s ease;
}

.plugin-card.expanded .plugin-chevron {
    transform: rotate(180deg);
}

.plugin-body {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.plugin-card.expanded .plugin-body {
    max-height: 300px;
}

.plugin-body ul {
    padding: 0 20px 16px 56px;
    list-style: disc;
}

.plugin-body li {
    margin-bottom: 6px;
    font-size: 0.92rem;
    color: var(--body-text);
    line-height: 1.5;
}

.plugin-docs-link {
    display: inline-block;
    margin: 0 0 16px 56px;
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--primary-blue);
}

/* ============================================ */
/* Section 9: Resources                         */
/* ============================================ */
.resources {
    padding: 80px 24px;
    background: var(--white);
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
    max-width: 800px;
    margin: 0 auto;
}

.resource-card {
    text-align: center;
    padding: 40px 32px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: box-shadow 0.2s ease;
}

.resource-card:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.resource-icon {
    margin: 0 auto 16px;
}

.resource-langguard-logo {
    height: 40px;
    margin: 0 auto 16px;
    object-fit: contain;
}

.resource-card h3 {
    font-size: 1.2rem;
    color: var(--dark-text);
    margin-bottom: 10px;
    font-weight: 600;
}

.resource-card p {
    font-size: 0.95rem;
    color: var(--muted-text);
    margin-bottom: 20px;
    line-height: 1.5;
}

/* ============================================ */
/* Section 10: Footer                           */
/* ============================================ */
.footer {
    background: var(--dark-blue);
    color: rgba(255, 255, 255, 0.8);
    padding: 48px 24px 24px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 32px;
    gap: 24px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-logo {
    width: 48px;
    height: 48px;
    border-radius: 50%;
}

.footer-title {
    font-size: 1.1rem;
    color: var(--white);
}

.footer-tagline {
    font-size: 0.85rem;
    opacity: 0.7;
    margin-top: 2px;
}

.footer-powered {
    font-size: 0.85rem;
    opacity: 0.7;
    margin-top: 4px;
}

.footer-powered a {
    color: var(--langguard-green);
}

.footer-powered a:hover {
    text-decoration: underline;
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-links a:hover {
    color: var(--white);
    text-decoration: none;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 20px;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.82rem;
    opacity: 0.6;
}

/* ============================================ */
/* Animations                                   */
/* ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================ */
/* Responsive: Tablet                           */
/* ============================================ */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .hero-title {
        font-size: 2.8rem;
    }

    .resources-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ============================================ */
/* Responsive: Mobile                           */
/* ============================================ */
@media (max-width: 768px) {
    .nav-hamburger {
        display: flex;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--dark-blue);
        flex-direction: column;
        padding: 16px 24px;
        gap: 16px;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    }

    .nav-links.open {
        display: flex;
    }

    .hero {
        padding: 120px 24px 60px;
        min-height: auto;
    }

    .hero-title {
        font-size: 2.2rem;
    }

    .hero-mascot {
        width: 140px;
        height: 140px;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .hero-pitch {
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.6rem;
    }

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

    .platforms-grid {
        gap: 20px;
    }

    .platform-item {
        min-width: 70px;
    }

    .platform-icon {
        width: 52px;
        height: 52px;
    }

    .screenshot-tabs {
        gap: 4px;
    }

    .screenshot-tab {
        padding: 6px 14px;
        font-size: 0.82rem;
    }

    .step {
        flex-direction: column;
        gap: 12px;
    }

    .resources-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .footer-brand {
        flex-direction: column;
        text-align: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}