:root {
  --bg-app: #0c0f14;
  --bg-card: #151a22;
  --bg-card-hover: #1b222d;
  --border-color: #262d3a;
  --border-hover: #00e5ff;
  --text-main: #f9fafb;
  --text-muted: #94a3b8;
  --text-sub: #64748b;
  --accent-cyan: #00e5ff;
  --accent-blue: #3b82f6;
  --accent-green: #00e676;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Monaco, "Cascadia Code", "JetBrains Mono", Consolas, monospace;
}

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

body {
  background-color: var(--bg-app);
  color: var(--text-main);
  font-family: var(--font-sans);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 48px 24px 64px 24px;
  width: 100%;
}

/* Header */
header {
  margin-bottom: 40px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 28px;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand-emblem {
  width: 56px;
  height: 56px;
  flex-shrink: 0;
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
}

h1 {
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-main);
  margin-bottom: 8px;
}

.subtitle {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* Platform Grid */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
  margin-bottom: 48px;
}

/* Platform Card */
.platform-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}

.platform-card:hover {
  background-color: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.card-top {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 16px;
}

.platform-icon {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-main);
}

.platform-icon svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

.card-title-group h2 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.2;
}

.platform-arch {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-sub);
  margin-top: 4px;
}

.card-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-sub);
  margin-bottom: 16px;
  padding-top: 12px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.file-name {
  color: var(--accent-cyan);
  font-weight: 500;
}

/* Download Button */
.download-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: #1e2633;
  color: var(--text-main);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 10px 16px;
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.download-btn svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.download-btn:hover {
  background-color: var(--accent-blue);
  border-color: var(--accent-blue);
  color: #ffffff;
}

.download-btn.primary {
  background-color: #0d3b66;
  border-color: var(--accent-blue);
  color: #ffffff;
}

.download-btn.primary:hover {
  background-color: #1d4ed8;
}

/* Footer / Extra info */
footer {
  margin-top: auto;
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-size: 0.88rem;
  color: var(--text-sub);
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

@media (max-width: 640px) {
  .container {
    padding: 24px 16px 40px 16px;
  }
  h1 {
    font-size: 1.75rem;
  }
  .platform-grid {
    grid-template-columns: 1fr;
  }
}