/* Dark Navy Theme */
:root {
  --color-bg: #0b1523;
  --color-bg-contrast: #152940;
  --color-primary: #1fb6ff;
  --color-primary-light: #65d6ff;
  --color-text: #e0e7ff;
  --color-text-muted: #a3adc8;
  --color-card-bg: #1b2a48;
  --color-border: #27527a;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
}
html, body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
header {
  background-color: var(--color-bg-contrast);
  padding: 1rem 1.5rem;
}
.nav-list {
  list-style: none;
  display: flex;
  gap: 1rem;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
}
.nav-list a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 600;
  padding: 0.3rem 0.5rem;
  border-radius: 4px;
  transition: background-color 0.2s ease, color 0.2s ease;
}
.nav-list a:hover,
.nav-list a:focus {
  background-color: var(--color-primary-light);
  color: var(--color-bg);
  outline: none;
}
.nav-list a[aria-current="page"] {
  color: var(--color-primary);
  border-bottom: 2px solid var(--color-primary);
}
main {
  flex-grow: 1;
  padding: 1rem 1.5rem 2rem;
  max-width: 900px;
  margin: 0 auto;
}
.hero {
  text-align: center;
}
.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 0.25rem;
}
.hero p {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  margin-top: 0;
  margin-bottom: 1.5rem;
}
.hero img {
  max-width: 100%;
  height: auto;
  margin: 0 auto;
  display: block;
}
article h1,
article h2,
h1, h2 {
  font-weight: 700;
  color: var(--color-primary);
  margin-top: 1rem;
  margin-bottom: 0.5rem;
}
article p,
article ul,
section p,
section ul {
  font-size: 1rem;
  color: var(--color-text);
}
article ul {
  padding-left: 1.25rem;
  margin-top: 0;
}
article ul li {
  margin-bottom: 0.4rem;
}
.project-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}
.card {
  background-color: var(--color-card-bg);
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  box-shadow: 0 2px 5px rgba(15, 30, 50, 0.3);
  transition: transform 0.15s ease-in-out;
}
.card:focus-within,
.card:hover {
  transform: translateY(-3px);
  border-color: var(--color-primary);
  box-shadow: 0 4px 10px rgba(31, 182, 255, 0.5);
  outline: none;
}
.card h2 {
  font-size: 1.25rem;
  margin-top: 0;
  margin-bottom: 0.5rem;
  color: var(--color-primary-light);
}
.card p {
  margin: 0;
  color: var(--color-text-muted);
}
[role="toolbar"] {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}
[role="toolbar"] button {
  background-color: var(--color-bg-contrast);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  padding: 0.4rem 1rem;
  border-radius: 20px;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}
[role="toolbar"] button[aria-pressed="true"] {
  background-color: var(--color-primary);
  color: var(--color-bg);
  border-color: var(--color-primary-light);
}
[role="toolbar"] button:hover,
[role="toolbar"] button:focus {
  background-color: var(--color-primary-light);
  color: var(--color-bg);
  border-color: var(--color-primary-light);
  outline: none;
}
.error-page {
  text-align: center;
  margin-top: 4rem;
}
.error-page h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  color: var(--color-primary);
}
.error-page p {
  font-size: 1.125rem;
  margin-bottom: 0.5rem;
}
footer {
  text-align: center;
  padding: 1rem 1.5rem;
  background-color: var(--color-bg-contrast);
  color: var(--color-text-muted);
  font-size: 0.9rem;
  flex-shrink: 0;
}
address {
  font-style: normal;
  color: var(--color-text-muted);
  margin-top: 0.5rem;
}
@media (max-width: 600px) {
  .nav-list {
    justify-content: center;
  }
  .nav-list li {
    flex: 1 0 auto;
    text-align: center;
  }
  main {
    padding: 1rem;
  }
  .hero h1 {
    font-size: 2rem;
  }
  .project-cards {
    grid-template-columns: 1fr;
  }
}