* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Poppins', sans-serif;
}

body {
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background-color: var(--bg-color);
  color: var(--text-main);
  transition: background-color 0.3s ease, color 0.3s ease;
}

header {
  background: var(--card-bg);
  color: var(--text-main);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 100px;
  box-shadow: 0 4px 10px var(--shadow-color);
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

header h1 {
  margin: 0;
  font-size: 2.2rem;
  font-weight: 600;
}

/* main layout */
.main-layout {
  display: flex;
  flex: 1;
  padding: 2rem;
  color: var(--text-main);
  max-width: 1200px;
  margin: 20px auto;
  width: 100%;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  width: 100%;
}

.project-card {
  background-color: var(--card-bg);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 15px var(--shadow-color);
  transition: transform 0.3s ease, box-shadow 0.3s ease, background-color 0.3s ease;
  display: flex;
  flex-direction: column;
}

.project-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 8px 25px var(--shadow-color);
}

.project-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 2px solid var(--border-color);
}

.placeholder-img {
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-hover));
  color: #fff;
  font-size: 1.5rem;
  font-weight: 600;
}

.project-content {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.project-content h3 {
  color: var(--accent);
  margin-bottom: 10px;
  font-size: 1.4rem;
}

.project-content p {
  color: var(--text-main);
  margin-bottom: 15px;
  line-height: 1.5;
  flex: 1;
}

.project-tags {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.project-tags span {
  background-color: var(--bg-color);
  color: var(--text-muted);
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid var(--border-color);
}

.project-link {
  display: inline-block;
  text-align: center;
  background-color: var(--accent);
  color: #fff;
  text-decoration: none;
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 500;
  transition: background-color 0.3s ease, transform 0.3s ease;
}

.project-link:hover {
  background-color: var(--accent-hover);
  transform: translateY(-2px);
}

footer {
  width: 100%;
  background-color: var(--footer-bg);
  color: var(--text-muted);
  text-align: center;
  height: 60px;
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: auto;
  transition: background-color 0.3s ease;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
  .main-layout {
    padding: 1rem;
  }
  
  .projects-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  }

  header h1 {
    font-size: 1.8rem;
  }
}