/* ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
   DD — Deep Downloader Landing Page
   Design System & Styles
   ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ */

/* ─── Design Tokens ─── */
:root {
    --bg-primary: #050810;
    --bg-secondary: #0A0F1E;
    --bg-card: #0E1425;
    --bg-card-hover: #131B30;
    --surface: #161E33;
    --border: rgba(255, 255, 255, 0.06);
    --border-hover: rgba(0, 229, 255, 0.2);

    --text-primary: #F0F2F5;
    --text-secondary: #8B95A8;
    --text-tertiary: #5A6478;

    --accent: #00E5FF;
    --accent-dim: rgba(0, 229, 255, 0.12);
    --accent-glow: rgba(0, 229, 255, 0.3);
    --gradient-start: #00E5FF;
    --gradient-end: #6C63FF;

    --success: #4CAF50;
    --warning: #FF9800;

    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 40px rgba(0, 229, 255, 0.15);

    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-main);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a { text-decoration: none; color: inherit; transition: color var(--transition); }
img { max-width: 100%; height: auto; display: block; }

/* ─── Particles Canvas ─── */
#particles-canvas {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ─── Navigation ─── */
#navbar {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    padding: 0 24px;
    transition: all var(--transition);
    background: transparent;
}

#navbar.scrolled {
    background: rgba(5, 8, 16, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.1rem;
    z-index: 10;
}

.logo-dd {
    color: var(--accent);
    font-weight: 900;
    font-size: 1.4rem;
    letter-spacing: -1px;
}

.logo-separator { color: var(--text-tertiary); font-weight: 300; }
.logo-text { color: var(--text-secondary); font-weight: 500; }

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

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition);
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px; left: 0;
    width: 0; height: 2px;
    background: var(--accent);
    transition: width var(--transition);
    border-radius: 1px;
}

.nav-links a:hover::after { width: 100%; }

.nav-cta {
    background: var(--accent-dim) !important;
    color: var(--accent) !important;
    padding: 8px 20px;
    border-radius: var(--radius-xl);
    border: 1px solid rgba(0, 229, 255, 0.2);
    font-weight: 600 !important;
}

.nav-cta:hover {
    background: rgba(0, 229, 255, 0.2) !important;
    border-color: rgba(0, 229, 255, 0.4);
}

.nav-cta::after { display: none !important; }

.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 10;
}

.nav-hamburger span {
    width: 24px; height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(5, 8, 16, 0.95);
    backdrop-filter: blur(20px);
    z-index: 999;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 24px;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition);
}

.mobile-menu.active { opacity: 1; pointer-events: all; }

.mobile-link {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-secondary);
    transition: color var(--transition);
}

.mobile-link:hover { color: var(--accent); }
.mobile-link.cta { color: var(--accent); }

/* ─── Hero Section ─── */
#hero {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 24px 80px;
    max-width: 1200px;
    margin: 0 auto;
    gap: 60px;
}

.hero-content { flex: 1; max-width: 560px; }

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: var(--accent-dim);
    border: 1px solid rgba(0, 229, 255, 0.15);
    border-radius: var(--radius-xl);
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 24px;
    animation: fadeInUp 0.8s ease;
}

.badge-dot {
    width: 6px; height: 6px;
    background: var(--accent);
    border-radius: 50%;
    animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    font-weight: 900;
    line-height: 1.05;
    letter-spacing: -2px;
    margin-bottom: 16px;
    animation: fadeInUp 0.8s ease 0.1s both;
}

.title-accent {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.title-dash { color: var(--text-tertiary); font-weight: 300; }
.title-sub { color: var(--text-primary); }

.hero-tagline {
    font-size: 1.25rem;
    color: var(--accent);
    font-weight: 600;
    margin-bottom: 16px;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-description {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 32px;
    animation: fadeInUp 0.8s ease 0.3s both;
}

.hero-actions {
    display: flex;
    gap: 14px;
    margin-bottom: 48px;
    animation: fadeInUp 0.8s ease 0.4s both;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 24px;
    animation: fadeInUp 0.8s ease 0.5s both;
    flex-wrap: wrap;
}

.stat { text-align: center; }

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
    letter-spacing: -1px;
}

.stat-unit { font-size: 1.2rem; color: var(--accent); }
.stat-label { font-size: 0.75rem; color: var(--text-tertiary); font-weight: 500; text-transform: uppercase; letter-spacing: 1px; }
.stat-divider { width: 1px; height: 40px; background: var(--border); }

/* ─── Hero Visual ─── */
.hero-visual {
    flex: 1;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 500px;
    animation: fadeInUp 1s ease 0.3s both;
}

.phone-mockup {
    position: absolute;
    width: 260px;
    border-radius: 28px;
    overflow: hidden;
    box-shadow: var(--shadow-card), var(--shadow-glow);
    border: 1px solid var(--border);
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.phone-mockup img {
    width: 100%;
    height: auto;
    display: block;
}

.phone-1 {
    transform: rotate(-6deg) translateX(-30px);
    z-index: 2;
}

.phone-1:hover { transform: rotate(-2deg) translateX(-30px) scale(1.03); }

.phone-2 {
    transform: rotate(6deg) translateX(50px) translateY(40px);
    z-index: 1;
    opacity: 0.9;
}

.phone-2:hover { transform: rotate(3deg) translateX(50px) translateY(40px) scale(1.03); opacity: 1; }

.hero-glow {
    position: absolute;
    width: 400px; height: 400px;
    background: radial-gradient(circle, var(--accent-glow), transparent 70%);
    z-index: 0;
    filter: blur(60px);
    animation: glow-pulse 4s ease-in-out infinite alternate;
}

@keyframes glow-pulse {
    0% { opacity: 0.4; transform: scale(0.9); }
    100% { opacity: 0.7; transform: scale(1.1); }
}

/* ─── Buttons ─── */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: var(--radius-xl);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: #050810;
    box-shadow: 0 4px 20px rgba(0, 229, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 229, 255, 0.4);
}

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

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

.btn-large { padding: 18px 36px; font-size: 1.05rem; }

/* ─── Sections ─── */
section {
    position: relative;
    z-index: 1;
    padding: 100px 24px;
}

.section-container { max-width: 1200px; margin: 0 auto; }

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-badge {
    display: inline-block;
    padding: 6px 16px;
    background: var(--accent-dim);
    border: 1px solid rgba(0, 229, 255, 0.15);
    border-radius: var(--radius-xl);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 2px;
    margin-bottom: 16px;
}

.section-header h2 {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 12px;
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 560px;
    margin: 0 auto;
}

/* ─── Features ─── */
#features { background: var(--bg-secondary); }

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px;
    transition: all var(--transition);
}

.feature-card:hover {
    border-color: var(--border-hover);
    background: var(--bg-card-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.feature-card.featured {
    grid-column: span 1;
    background: linear-gradient(135deg, rgba(0, 229, 255, 0.08), rgba(108, 99, 255, 0.05));
    border-color: rgba(0, 229, 255, 0.15);
}

.feature-icon {
    width: 52px; height: 52px;
    display: flex; align-items: center; justify-content: center;
    background: var(--accent-dim);
    border-radius: var(--radius-md);
    color: var(--accent);
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ─── Sources ─── */
.sources-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 16px;
}

.source-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 24px 20px;
    text-align: center;
    transition: all var(--transition);
}

.source-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.source-icon { font-size: 2rem; margin-bottom: 10px; }
.source-card h4 { font-size: 0.95rem; font-weight: 700; margin-bottom: 6px; }
.source-card p { font-size: 0.75rem; color: var(--text-tertiary); }

.source-type {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.source-type.api { background: rgba(0, 229, 255, 0.12); color: var(--accent); }
.source-type.scraper { background: rgba(108, 99, 255, 0.12); color: #8B80FF; }

/* ─── Themes ─── */
#themes { background: var(--bg-secondary); }

.themes-showcase {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.theme-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    transition: all var(--transition);
}

.theme-card:hover { transform: translateY(-6px); }

.theme-preview {
    width: 140px; height: 200px;
    border-radius: var(--radius-lg);
    border: 2px solid var(--border);
    position: relative;
    overflow: hidden;
    transition: border-color var(--transition);
}

.theme-card.active .theme-preview { border-color: var(--accent); box-shadow: var(--shadow-glow); }

.theme-accent {
    position: absolute;
    bottom: 16px; left: 16px; right: 16px;
    height: 4px;
    border-radius: 2px;
}

.theme-card span { font-size: 0.85rem; font-weight: 600; color: var(--text-secondary); }
.theme-card.active span { color: var(--accent); }

/* ─── Architecture ─── */
.arch-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 48px;
}

.arch-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: all var(--transition);
}

.arch-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-3px);
}

.arch-label {
    display: inline-block;
    padding: 3px 10px;
    background: var(--accent-dim);
    border-radius: 6px;
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 10px;
}

.arch-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 8px; }
.arch-card p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.6; }

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}

.tech-tag {
    padding: 8px 18px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    font-family: var(--font-mono);
    transition: all var(--transition);
}

.tech-tag:hover { border-color: var(--accent); color: var(--accent); }

/* ─── Download Section ─── */
#download {
    background: var(--bg-secondary);
}

.download-card {
    max-width: 680px;
    margin: 0 auto;
    text-align: center;
    background: linear-gradient(135deg, rgba(0, 229, 255, 0.06), rgba(108, 99, 255, 0.04));
    border: 1px solid rgba(0, 229, 255, 0.12);
    border-radius: var(--radius-xl);
    padding: 60px 40px;
}

.download-icon {
    width: 96px; height: 96px;
    border-radius: var(--radius-lg);
    margin: 0 auto 24px;
    box-shadow: var(--shadow-glow);
}

.download-card h2 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.download-card > p {
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-size: 1.05rem;
}

.download-specs {
    display: flex;
    justify-content: center;
    gap: 32px;
    margin-bottom: 36px;
    flex-wrap: wrap;
}

.spec { text-align: center; }
.spec-label { display: block; font-size: 0.7rem; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 1px; font-weight: 600; }
.spec-value { display: block; font-size: 0.95rem; font-weight: 700; color: var(--text-primary); margin-top: 4px; }

.download-buttons {
    display: flex;
    justify-content: center;
    gap: 14px;
    flex-wrap: wrap;
}

/* ─── Footer ─── */
footer {
    position: relative;
    z-index: 1;
    padding: 60px 24px 30px;
    border-top: 1px solid var(--border);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-brand { margin-bottom: 32px; }
.footer-logo { font-size: 2rem; font-weight: 900; color: var(--accent); }
.footer-brand p { color: var(--text-tertiary); margin-top: 6px; }

.footer-links {
    display: flex;
    gap: 80px;
    margin-bottom: 40px;
}

.footer-col { display: flex; flex-direction: column; gap: 10px; }
.footer-col h5 { font-size: 0.85rem; font-weight: 700; color: var(--text-primary); margin-bottom: 4px; text-transform: uppercase; letter-spacing: 1px; }
.footer-col a { font-size: 0.9rem; color: var(--text-secondary); transition: color var(--transition); }
.footer-col a:hover { color: var(--accent); }

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}

.footer-bottom p { font-size: 0.85rem; color: var(--text-tertiary); }
.footer-bottom strong { color: var(--accent); }
.footer-copy { font-size: 0.8rem !important; }

/* ─── Animations ─── */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.animate-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ─── Responsive ─── */
@media (max-width: 1024px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .sources-grid { grid-template-columns: repeat(3, 1fr); }
    .arch-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    #hero {
        flex-direction: column;
        padding-top: 100px;
        min-height: auto;
        gap: 40px;
    }

    .hero-content { max-width: 100%; text-align: center; }
    .hero-actions { justify-content: center; }
    .hero-stats { justify-content: center; }

    .hero-visual { min-height: 380px; }
    .phone-mockup { width: 200px; }

    .nav-links { display: none; }
    .nav-hamburger { display: flex; }
    .mobile-menu { display: flex; }

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

    .themes-showcase { gap: 12px; }
    .theme-preview { width: 100px; height: 150px; }

    .download-card { padding: 40px 24px; }
    .footer-links { flex-direction: column; gap: 32px; }
    .footer-bottom { flex-direction: column; text-align: center; }

    .download-specs { gap: 20px; }
}

@media (max-width: 480px) {
    .sources-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-title { letter-spacing: -1px; }
    .btn { padding: 12px 22px; font-size: 0.9rem; }
    .btn-large { padding: 14px 28px; }
}