* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: #0f1115;
  color: #f1f1f1;
}

.site-header {
  padding: 2.5rem 1.5rem 1rem;
  text-align: center;
}

.site-header h1 {
  margin: 0 0 0.25rem;
  font-size: 2.25rem;
}

.site-header p {
  margin: 0;
  color: #9aa0ab;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0.5rem 1.5rem 3rem;
}

.about-me {
  background: #1b1e25;
  border: 1px solid #2c303a;
  border-radius: 14px;
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.about-me h2 {
  margin: 0 0 0.5rem;
  font-size: 1.25rem;
}

.about-me p {
  margin: 0;
  color: #9aa0ab;
  font-size: 0.95rem;
  line-height: 1.5;
}

.section-title {
  margin: 0 0 1rem;
  font-size: 1.5rem;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: #1b1e25;
  border: 1px solid #2c303a;
  border-radius: 14px;
  padding: 1.5rem;
  cursor: pointer;
  transition: transform 0.15s ease, border-color 0.15s ease;
}

.project-card:hover {
  transform: translateY(-3px);
  border-color: #4f7cff;
}

.project-card h2 {
  margin: 0 0 0.5rem;
  font-size: 1.25rem;
}

.project-card p {
  margin: 0 0 1rem;
  color: #9aa0ab;
  font-size: 0.95rem;
}

.open-hint {
  color: #4f7cff;
  font-size: 0.9rem;
  font-weight: 600;
}

.viewer-overlay {
  position: fixed;
  inset: 0;
  background: #0f1115;
  display: flex;
  flex-direction: column;
  z-index: 100;
}

.viewer-overlay[hidden] {
  display: none;
}

.viewer-bar {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  background: #1b1e25;
  border-bottom: 1px solid #2c303a;
}

.viewer-bar button {
  background: #4f7cff;
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.5rem 1rem;
  cursor: pointer;
  font-size: 0.95rem;
}

.viewer-bar button:hover {
  background: #3d66e0;
}

#viewer-title {
  font-weight: 600;
  color: #f1f1f1;
}

#viewer-frame {
  flex: 1;
  width: 100%;
  border: none;
  background: #fff;
}