/* ===== CSS Variables - Dark Mode (Default) ===== */
:root {
    --color-bg: #000000;
    --color-bg-secondary: #0a0a0a;
    --color-bg-card: #111111;
    --color-text: #ffffff;
    --color-text-muted: #f2f2f2;
    --color-accent: #ffffff;
    --color-highlight: rgba(255,255,255,0.06);
    --color-border: #222222;
    --color-link: #ffffff;
    --color-link-hover: #aaaaaa;
    
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
    
    --content-width: min(65%, 800px);
    --max-width: 1000px;
    --radius: 0;
    --radius-lg: 0;
    --shadow: none;
    --transition: 0.15s ease;
}

/* ===== Light Mode ===== */
[data-theme="light"] {
    --color-bg: #ffffff;
    --color-bg-secondary: #fafafa;
    --color-bg-card: #f5f5f5;
    --color-text: #000000;
    --color-text-muted: #666666;
    --color-accent: #000000;
    --color-border: #e0e0e0;
    --color-link: #000000;
    --color-link-hover: #444444;
    --color-highlight: rgba(0,0,0,0.06);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    color: var(--color-link);
    text-decoration: none;
    transition: color var(--transition);
}

a:hover {
    color: var(--color-link-hover);
    text-decoration: underline;
}

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

/* ===== Navbar ===== */
.navbar {
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 1rem;
    color: var(--color-text);
    text-decoration: none;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.navbar-brand:hover {
    color: var(--color-text-muted);
    text-decoration: none;
}

.navbar-brand img {
    height: 24px;
    width: auto;
}

.navbar-menu {
    display: flex;
    list-style: none;
    gap: 0;
    align-items: center;
}

.navbar-item {
    padding: 0.5rem 0.75rem;
    color: var(--color-text-muted);
    font-weight: 400;
    font-size: 0.875rem;
    transition: color var(--transition), background var(--transition);
}

.navbar-item:hover {
    color: var(--color-text);
    background: var(--color-highlight);
    text-decoration: none;
}

.navbar-item.active {
    color: var(--color-text);
    font-weight: 500;
    background: var(--color-highlight);
}

.desktop-only {
    display: block;
}

/* Theme Toggle Button */
.theme-toggle {
    padding: 0.5rem;
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
    cursor: pointer;
    transition: all var(--transition);
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
}

.theme-toggle:hover {
    border-color: var(--color-text);
}

/* Language Switcher */
.lang-switcher {
    position: relative;
}

.lang-btn {
    padding: 0.4rem 0.6rem;
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
    cursor: pointer;
    transition: all var(--transition);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.05em;
}

.lang-btn:hover {
    border-color: var(--color-text);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 0.25rem;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    min-width: 80px;
    display: none;
    flex-direction: column;
}

.lang-dropdown.show {
    display: flex;
}

.lang-option {
    padding: 0.5rem 0.75rem;
    color: var(--color-text-muted);
    font-size: 0.75rem;
    transition: all var(--transition);
    cursor: pointer;
}

.lang-option:hover {
    background: var(--color-highlight);
    color: var(--color-text);
    text-decoration: none;
}

/* ===== Hero Section ===== */;
}

/* Language Switcher */
.lang-switcher {
    position: relative;
}

.lang-btn {
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    color: var(--color-text);
    cursor: pointer;
    transition: all var(--transition);
    font-size: 0.875rem;
    font-weight: 500;
}

.lang-btn:hover {
    border-color: var(--color-accent);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 0.5rem;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    min-width: 150px;
    display: none;
    flex-direction: column;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.lang-dropdown.show {
    display: flex;
}

.lang-option {
    padding: 0.75rem 1rem;
    color: var(--color-text);
    transition: all var(--transition);
    cursor: pointer;
}

.lang-option:hover {
    background: var(--color-bg-secondary);
    text-decoration: none;
}

/* ===== Hero Section ===== */
.hero {
    background: var(--color-bg);
    padding: 5rem 1.5rem;
    text-align: center;
    border-bottom: 1px solid var(--color-border);
}

.hero-container {
    max-width: var(--content-width);
    margin: 0 auto;
}

.hero-tagline {
    display: inline-block;
    font-size: 0.75rem;
    color: var(--color-text-muted);
    font-weight: 400;
    margin-bottom: 2rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.hero-logo {
    width: 80px;
    height: 80px;
    margin-bottom: 1.5rem;
}

[data-theme="light"] .hero-logo,
[data-theme="light"] .navbar-brand img {
    filter: invert(1);
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 300;
    margin-bottom: 1.5rem;
    color: var(--color-text);
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.hero-subtitle {
    font-size: 1rem;
    color: var(--color-text-muted);
    max-width: 100%;
    margin: 0 auto 2.5rem;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    font-weight: 400;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition);
    border: 1px solid var(--color-border);
    text-decoration: none;
    background: transparent;
    color: var(--color-text);
}

.btn:hover {
    text-decoration: none;
    border-color: var(--color-text);
    background: var(--color-highlight);
    color: var(--color-text);
}

.btn-primary {
    background: var(--color-text);
    color: var(--color-bg);
    border-color: var(--color-text);
}

.btn-primary:hover {
    background: var(--color-highlight);
    color: var(--color-text);
    border-color: var(--color-text);
}

.btn-secondary {
    background: transparent;
    color: var(--color-text);
}

.btn-secondary:hover {
    background: var(--color-bg-card);
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 4rem 1.5rem;
    width: 100%;
}

/* ===== Section ===== */
.section {
    margin-bottom: 4rem;
    padding-bottom: 4rem;
    border-bottom: 1px solid var(--color-border);
}

.section:last-of-type {
    border-bottom: none;
}

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

.section-title {
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 1rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

.section-description {
    color: var(--color-text);
    font-size: 1rem;
    max-width: 100%;
    line-height: 1.8;
}

/* ===== Features as Sections ===== */
.features-grid {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.feature-card {
    padding: 0;
    border: none;
    background: transparent;
}

.feature-icon {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.feature-title {
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.feature-description {
    color: var(--color-text-muted);
    line-height: 1.7;
    font-size: 0.875rem;
}

/* ===== Links Section ===== */
.links-section {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--color-border);
}

.links-title {
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 1rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

.links-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.link-item {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--color-border);
    color: var(--color-text-muted);
    transition: all var(--transition);
    font-size: 0.8rem;
}

.link-item:hover {
    border-color: var(--color-text);
    color: var(--color-text);
    background: var(--color-highlight);
    text-decoration: none;
}

.link-item span {
    font-size: 0.875rem;
}

/* ===== About Page ===== */
.about-header {
    margin-bottom: 3rem;
}

.about-title {
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 1rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

.about-intro {
    color: var(--color-text);
    font-size: 1rem;
    max-width: 100%;
    line-height: 1.8;
}

.about-section {
    padding: 2rem 0;
    border-bottom: 1px solid var(--color-border);
}

.about-section:last-of-type {
    border-bottom: none;
}

.about-section-title {
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
    color: var(--color-text);
}

.about-section-text {
    color: var(--color-text-muted);
    line-height: 1.8;
    font-size: 0.875rem;
}

/* ===== Footer ===== */
.footer {
    background: var(--color-bg);
    border-top: 1px solid var(--color-border);
    padding: 2rem 1.5rem;
    margin-top: auto;
}

.footer-container {
    max-width: var(--content-width);
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-section {
    flex: 1;
    min-width: 120px;
}

.footer-section h4 {
    font-size: 0.7rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
    color: var(--color-text-muted);
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.footer-links a {
    color: var(--color-text-muted);
    font-size: 0.8rem;
    transition: color var(--transition);
}

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

.footer-bottom {
    max-width: var(--content-width);
    margin: 1.5rem auto 0;
    padding-top: 1.5rem;
    border-top: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-text-muted);
    font-size: 0.75rem;
}

/* ===== Code Blocks ===== */
code {
    font-family: var(--font-mono);
    background: var(--color-bg-card);
    padding: 0.2rem 0.4rem;
    font-size: 0.9em;
}

pre {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 1.5rem;
    overflow-x: auto;
}

pre code {
    background: none;
    padding: 0;
}

/* ===== Utility Classes ===== */
.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    :root {
        --content-width: 80%;
    }
}

@media (max-width: 768px) {
    :root {
        --content-width: 90%;
    }
    
    .hero {
        padding: 3rem 1rem;
    }
    
    .hero-logo {
        width: 60px;
        height: 60px;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .hero-subtitle {
        font-size: 0.875rem;
    }
    
    .hero-tagline {
        font-size: 0.65rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: stretch;
    }
    
    .btn {
        justify-content: center;
    }
    
    .navbar-container {
        padding: 0 1rem;
    }
    
    .navbar-item {
        padding: 0.4rem 0.5rem;
        font-size: 0.75rem;
    }
    
    .desktop-only {
        display: none;
    }
    
    .main-content {
        padding: 2rem 1rem;
    }
    
    .footer-container {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .footer-section {
        min-width: 100%;
    }
}

@media (max-width: 480px) {
    :root {
        --content-width: 95%;
    }
    
    .navbar-brand {
        font-size: 0.875rem;
    }
    
    .navbar-brand img {
        height: 20px;
    }
}
    
    .footer-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
}