:root {
  --primary: #1f2937;
  --accent-start: #3b82f6;
  --accent-end: #8b5cf6;
  --accent-gradient: linear-gradient(135deg, var(--accent-start) 0%, var(--accent-end) 100%);
  --text: #111827;
  --text-muted: #6b7280;
  --text-lighter: #9ca3af;
  --bg: #ffffff;
  --bg-off-white: #fafafa;
  --card-bg: rgba(255, 255, 255, 0.65);
  --card-border: rgba(255, 255, 255, 0.28);
  --border: #e5e7eb;
  --pill: rgba(255, 255, 255, 0.9);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 12px 30px rgba(0, 0, 0, 0.12);
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme='dark'] {
  --primary: #f9fafb;
  --text: #f9fafb;
  --text-muted: #9ca3af;
  --text-lighter: #6b7280;
  --bg: transparent;
  --bg-off-white: #1f2937;
  --card-bg: rgba(31, 41, 55, 0.55);
  --card-border: rgba(255, 255, 255, 0.12);
  --border: #374151;
  --pill: rgba(31, 41, 55, 0.9);
}

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

html {
  scroll-behavior: smooth;
}

body {
  position: relative;
  min-height: 100vh;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  transition: color 0.2s var(--ease);
  -webkit-font-smoothing: antialiased;
}

[data-theme='dark'] body {
  background-color: #000;
}

[data-theme='dark'] body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse 80% 60% at 20% 20%, rgba(55, 20, 90, 0.45) 0%, transparent 55%),
    radial-gradient(ellipse 70% 50% at 80% 75%, rgba(15, 40, 90, 0.4) 0%, transparent 50%),
    radial-gradient(ellipse 60% 80% at 50% 100%, rgba(30, 10, 60, 0.35) 0%, transparent 45%),
    linear-gradient(135deg, #000000 0%, #0f0520 25%, #050a18 50%, #120818 75%, #000000 100%);
  background-size: 200% 200%, 200% 200%, 200% 200%, 400% 400%;
  animation: cosmic-drift 10s ease-in-out infinite;
}

@keyframes cosmic-drift {
  0%, 100% {
    background-position: 0% 50%, 100% 50%, 50% 100%, 0% 50%;
  }
  33% {
    background-position: 100% 0%, 0% 100%, 80% 0%, 50% 0%;
  }
  66% {
    background-position: 50% 100%, 100% 0%, 0% 50%, 100% 100%;
  }
}

.container {
  max-width: 980px;
  width: 100%;
  margin: 0 auto;
  padding: 0 40px 120px;
}

.header {
  text-align: center;
  padding: 80px 40px 16px;
}

.logo {
  display: block;
  height: 108px;
  width: auto;
  margin: 0 auto;
}

.hero {
  max-width: 900px;
  width: 100%;
  margin: 48px auto 0;
  font-size: 30pt;
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: var(--text);
  text-wrap: balance;
}

.filter-wrap {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  max-width: 980px;
  margin: 14px auto 42px;
}

.filter-line {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 980px;
  max-width: 100%;
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent 0%,
    var(--border) 18%,
    var(--border) 82%,
    transparent 100%
  );
  z-index: 0;
}

.filter-pill {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: 4px;
  width: fit-content;
  margin: 0;
  padding: 4px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-off-white);
}

.filter-segment {
  padding: 10px 28px;
  font: inherit;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-muted);
  background: transparent;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: color 0.2s var(--ease), background 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.filter-segment:hover {
  color: var(--text);
}

.filter-segment.active {
  background: var(--accent-gradient);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.filter-segment.active:hover {
  opacity: 0.92;
  color: #fff;
}

.masonry-grid {
  column-count: 2;
  column-gap: 24px;
}

.card {
  break-inside: avoid;
  margin-bottom: 24px;
  padding: 0;
  border: 4px solid var(--card-border);
  border-radius: 15px;
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease), transform 0.2s var(--ease), background 0.2s var(--ease);
}

.card-image {
  width: 100%;
  height: auto;
  display: block;
  border-top-left-radius: 11px;
  border-top-right-radius: 11px;
  object-fit: cover;
}

.card-body {
  padding: 20px;
}

.card:hover {
  border-color: rgba(59, 130, 246, 0.35);
  background: var(--card-bg);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
  line-height: 1.4;
  color: var(--primary);
}

.card-category {
  display: inline-block;
  margin-bottom: 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.card-description {
  margin-bottom: 16px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-muted);
}

.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 8px;
}

.card-github {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 6px 14px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--text);
  background: var(--bg-off-white);
  border: 1px solid var(--border);
  border-radius: 999px;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease), color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.card-github:hover {
  background: var(--card-bg);
  border-color: var(--accent-start);
  color: var(--accent-start);
  box-shadow: var(--shadow-md);
}

[data-theme='dark'] .card-github {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.15);
  color: var(--text);
}

[data-theme='dark'] .card-github:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.3);
  color: #ffffff;
}

.github-icon {
  display: block;
  flex-shrink: 0;
}

.card-btn-xs {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 6px 16px;
  font-size: 12px;
  font-weight: 600;
  color: #ffffff;
  background: var(--accent-gradient);
  border-radius: 999px;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.card-btn-xs:hover {
  opacity: 0.92;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
  color: #ffffff;
}

.theme-toggle-container {
  position: fixed;
  bottom: 40px;
  right: 40px;
  z-index: 100;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--pill);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-md);
  cursor: pointer;
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.theme-toggle:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-lg);
}

.theme-icon {
  font-size: 20px;
  line-height: 1;
}

@media (max-width: 1024px) {
  .container {
    padding-inline: 24px;
  }
}

@media (max-width: 768px) {
  .header {
    padding: 60px 24px 12px;
  }

  .hero {
    font-size: 24pt;
  }

  .masonry-grid {
    column-count: 1;
    column-gap: 20px;
  }
}

@media (max-width: 640px) {
  .container {
    padding-inline: 16px;
  }

  .header {
    padding: 48px 16px 22px;
  }

  .hero {
    font-size: 20pt;
  }

  .filter-wrap {
    margin: 20px auto 34px;
  }

  .filter-segment {
    padding: 10px 20px;
    font-size: 14px;
  }

  .masonry-grid {
    column-gap: 16px;
  }

  .card {
    margin-bottom: 16px;
  }

  .card-body {
    padding: 16px;
  }

  .theme-toggle-container {
    bottom: 24px;
    right: 24px;
  }
}