:root {
  --fs-xl: clamp(2.5rem, 5vw, 4rem);
  --fs-lg: 1.5rem;
  --fs-md: 1.1rem;
  --fs-sm: 0.9rem;

  --dark-bg: #0d0d0d;
  --dark-gray: #1a1a1a;
  --primary: #306bac;
  --secondary: #6f9ceb;
  --accent: #918ef4;
  --text-light: #f0f0f0;
  --transition-speed: 0.3s;
}

.article-page {
  background: var(--dark-bg);
  padding: 60px 16px;
}

.article {
  background: #ffffff;
  color: #111;
  max-width: 800px;
  margin: 0 auto;
  padding: 3rem 2rem;
  border-radius: 12px;
  box-shadow: 0 12px 40px rgba(48, 107, 172, 0.15);
}

.article-tag {
  display: inline-block;
  background: var(--secondary);
  color: #fff;
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  font-size: var(--fs-sm);
  margin-bottom: 1rem;
}

.article h1 {
  font-size: var(--fs-xl);
  line-height: 1.2;
  margin-bottom: 0.5rem;
  color: #111;
}

.article-meta {
  font-size: var(--fs-sm);
  color: #666;
  margin-bottom: 2rem;
}

.article h2 {
  font-size: var(--fs-lg);
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  color: var(--primary);
}

.article p {
  font-size: var(--fs-md);
  line-height: 1.6;
  margin-bottom: 1rem;
  color: #222;
}

.article a {
  color: var(--primary);
  text-decoration: underline;
}

.article a:hover {
  color: var(--accent);
}

.references {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--secondary);
}

.references li {
  font-size: var(--fs-sm);
  margin-bottom: 0.8rem;
  color: #333;
}

.blog-page {
  padding: 40px 16px;
}

.blog-header {
  text-align: center;
  padding: 30px 20px;
  margin-bottom: 20px;
}

.blog-header h1 {
  font-size: var(--fs-xl);
  color: var(--text-light);
  margin: 0;
}

.blog-header p {
  margin-top: 10px;
  color: var(--text-light);
  font-size: var(--fs-md);
}

.categories {
  display: flex;
  justify-content: center;
  gap: 15px;
  padding: 15px 0;
}

.categories button {
  padding: 8px 16px;
  border-radius: 6px;
  font-weight: bold;
  border: none;
  cursor: pointer;
  background: var(--dark-gray);
  color: var(--text-light);
  transition: background var(--transition-speed), color var(--transition-speed);
}

.categories button.active,
.categories button:hover {
  background: var(--primary);
  color: var(--text-light);
}

.articles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  padding: 20px;
  max-width: 1400px;
  margin: 0 auto;
}

.article-card {
  background: var(--dark-gray);
  padding: 16px;
  display: none;
  flex-direction: column;
  border-radius: 10px;
  box-shadow: 0 6px 15px rgba(0,0,0,0.25);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
  font-size: 0.95rem;
}

.article-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 25px rgba(0,0,0,0.35);
}

.article-card img {
  width: 100%;
  height: 140px;
  border-radius: 6px;
  margin-bottom: 10px;
  object-fit: cover;
}

.article-card h3 {
  margin: 0 0 8px 0;
  color: var(--text-light);
}

.article-card p {
  color: #ccc;
  flex-grow: 1;
}

.article-card a {
  text-decoration: none;
  font-weight: bold;
  margin-top: 8px;
  display: inline-block;
  color: var(--primary);
}

.article-card a:hover {
  color: var(--accent);
}

@media (max-width: 1024px) {
  .articles {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  }
}

@media (max-width: 768px) {
  .article-page {
    padding: 50px 12px;
  }

  .article {
    padding: 2rem 1.5rem;
  }

  .article h1 {
    font-size: 2.2rem;
  }

  .articles {
    gap: 14px;
  }

  .article-card {
    padding: 14px;
  }

  .categories {
    flex-wrap: wrap;
    gap: 10px;
  }
}

@media (max-width: 480px) {
  .article {
    padding: 1.5rem 1.2rem;
  }

  .article h1 {
    font-size: 1.9rem;
  }

  .article p {
    font-size: 1rem;
  }

  .article-card {
    padding: 12px;
  }
}

.article-page .nav,
.article-page .nav-links li a,
.article-page .nav-links li a:hover {
  background: var(--dark-gray) !important;
  color: var(--text-light) !important;
}

.article-page .nav-links li a:hover {
  background: var(--dark-gray) !important;
  color: var(--secondary) !important;
}

.back-btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: var(--primary);
  color: #fff !important;
  border-radius: 4px;
  font-weight: bold;
  font-size: var(--fs-sm);
  text-decoration: none;
  transition: transform var(--transition-speed), background var(--transition-speed), color var(--transition-speed);
}

.back-btn:hover {
  transform: translateY(-2px);
  background: var(--accent);
  color: #fff !important;
}