/* ========================================
   Tvastar Landing — Dark Cosmic Theme
   Mobile-first, no frameworks
   ======================================== */

:root {
  --bg: #0a0a14;
  --bg-card: #12121f;
  --bg-card-hover: #1a1a2e;
  --text: #e0e0e8;
  --text-muted: #8888a0;
  --text-heading: #f0f0ff;
  --accent: #7c5cfc;
  --accent-hover: #9b7dff;
  --accent-glow: rgba(124, 92, 252, 0.25);
  --border: #1e1e32;
  --radius: 12px;
  --radius-sm: 8px;
  --max-width: 1120px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover { color: var(--accent-hover); }

h1, h2, h3, h4 {
  color: var(--text-heading);
  line-height: 1.3;
  font-weight: 700;
}

h1 { font-size: clamp(1.75rem, 4vw, 2.75rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.1rem, 2vw, 1.35rem); }

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ========================================
   Header
   ======================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 10, 20, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-heading);
  font-weight: 700;
  font-size: 1.2rem;
  text-decoration: none;
}
.logo:hover { color: var(--accent); }
.logo-icon { font-size: 1.4rem; }

.main-nav { flex: 1; }

.nav-list {
  display: none;
  list-style: none;
  gap: 4px;
  flex-direction: column;
  position: absolute;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  padding: 12px 20px;
}
.nav-list.open { display: flex; }

.nav-list a {
  display: block;
  padding: 10px 12px;
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  transition: all 0.2s;
}
.nav-list a:hover, .nav-list a.active {
  color: var(--text-heading);
  background: var(--bg-card);
}

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: 0.2s;
}

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

.lang-link {
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}
.lang-link:hover {
  color: var(--text-heading);
  background: var(--bg-card);
}

.header-cta { display: none; }

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 20px var(--accent-glow);
}
.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  box-shadow: 0 6px 28px var(--accent-glow);
  transform: translateY(-1px);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.1rem;
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.85rem;
}

.icon-telegram {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

/* ========================================
   CTA Block
   ======================================== */
.cta-block {
  margin: 24px 0;
  text-align: center;
}

/* ========================================
   Hero
   ======================================== */
.hero {
  position: relative;
  padding: 80px 0 60px;
  overflow: hidden;
  text-align: center;
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin-bottom: 16px;
  background: linear-gradient(135deg, #f0f0ff, var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-visual {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 500px;
  height: 500px;
  pointer-events: none;
}

.hero-glow {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  filter: blur(60px);
  opacity: 0.5;
}

/* ========================================
   Section Titles
   ======================================== */
.section-title {
  text-align: center;
  margin-bottom: 48px;
}

/* ========================================
   Features Grid
   ======================================== */
.features {
  padding: 80px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.feature-card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-decoration: none;
  transition: all 0.25s;
}
.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 32px var(--accent-glow);
}

.feature-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.feature-card h3 {
  margin-bottom: 8px;
}

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

/* ========================================
   How It Works
   ======================================== */
.how-it-works {
  padding: 80px 0;
}

.steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  max-width: 700px;
  margin: 0 auto;
}

.step {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.step-num {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 1.2rem;
  border-radius: 50%;
}

.step h3 { margin-bottom: 4px; }
.step p { color: var(--text-muted); font-size: 0.95rem; }

/* ========================================
   Social Proof / Stats
   ======================================== */
.social-proof {
  padding: 60px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  text-align: center;
}

.stat-num {
  display: block;
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 800;
  color: var(--accent);
}

.stat-label {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ========================================
   Bottom CTA
   ======================================== */
.bottom-cta {
  padding: 80px 0;
  text-align: center;
}

.bottom-cta h2 {
  margin-bottom: 12px;
}

.bottom-cta p {
  color: var(--text-muted);
  margin-bottom: 8px;
}

/* ========================================
   Page (single SEO pages)
   ======================================== */
.page {
  padding: 60px 0;
}

.page-hero {
  text-align: center;
  margin-bottom: 48px;
}

.page-hero h1 { margin-bottom: 12px; }

.subtitle {
  color: var(--text-muted);
  font-size: 1.1rem;
}

.page-content {
  max-width: 720px;
  margin: 0 auto;
}

.page-content h2 {
  margin-top: 48px;
  margin-bottom: 16px;
}

.page-content ul, .page-content ol {
  margin: 16px 0;
  padding-left: 24px;
}

.page-content li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.page-content li strong {
  color: var(--text-heading);
}

.page-content p {
  margin-bottom: 16px;
}

.page-content a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-cta-bottom {
  margin-top: 48px;
}

/* ========================================
   FAQ Accordion
   ======================================== */
.faq-section {
  max-width: 720px;
  margin: 48px auto;
}

.faq-title {
  margin-bottom: 24px;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.faq-item summary {
  padding: 16px 20px;
  cursor: pointer;
  font-weight: 600;
  color: var(--text-heading);
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.2s;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
  content: '+';
  font-size: 1.3rem;
  color: var(--accent);
  flex-shrink: 0;
  margin-left: 12px;
  transition: transform 0.2s;
}

.faq-item[open] summary::after {
  content: '−';
}

.faq-item summary:hover {
  background: var(--bg-card-hover);
}

.faq-answer {
  padding: 0 20px 16px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ========================================
   Blog
   ======================================== */
.blog-list {
  padding: 60px 0;
}

.blog-list h1 {
  text-align: center;
  margin-bottom: 48px;
}

.blog-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.blog-card {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: all 0.25s;
}
.blog-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.blog-card a {
  text-decoration: none;
  color: inherit;
}

.blog-card img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
}

.blog-card-body {
  padding: 20px;
}

.blog-card-body time {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.blog-card-body h2 {
  font-size: 1.15rem;
  margin: 8px 0;
}

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

/* Blog Post */
.blog-post {
  padding: 60px 0;
}

.post-header {
  text-align: center;
  margin-bottom: 40px;
}

.post-header time {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.post-header h1 { margin: 12px 0 8px; }

.post-content {
  max-width: 720px;
  margin: 0 auto;
}

.post-content h2 {
  margin-top: 40px;
  margin-bottom: 16px;
}

.post-content h3 {
  margin-top: 32px;
  margin-bottom: 12px;
}

.post-content p {
  margin-bottom: 16px;
}

.post-content ul, .post-content ol {
  margin: 16px 0;
  padding-left: 24px;
}

.post-content li {
  margin-bottom: 8px;
}

.post-footer {
  margin-top: 48px;
  text-align: center;
}

/* ========================================
   Footer
   ======================================== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 48px 0 32px;
  margin-top: 40px;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  text-align: center;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.footer-tagline {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
}

.footer-nav a {
  color: var(--text-muted);
  font-size: 0.9rem;
}
.footer-nav a:hover { color: var(--text-heading); }

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

/* ========================================
   Desktop (768px+)
   ======================================== */
@media (min-width: 768px) {
  .nav-toggle { display: none; }

  .nav-list {
    display: flex;
    flex-direction: row;
    position: static;
    background: transparent;
    border: none;
    padding: 0;
    gap: 4px;
  }

  .header-cta { display: inline-flex; }

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

  .stats-grid {
    grid-template-columns: repeat(3, 1fr);
  }

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

/* ========================================
   Large Desktop (1024px+)
   ======================================== */
@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .hero {
    padding: 120px 0 80px;
  }

  .blog-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}