:root {
  --theme-main-bg: #f4f5f7;
  --theme-main-surface: #ffffff;
  --theme-main-text: #1f2937;
  --theme-main-muted: #6b7280;
  --theme-main-line: #e5e7eb;
  --theme-main-accent: #0f766e;
  --theme-main-accent-contrast: #ffffff;
  --theme-main-radius: 0.75rem;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Source Sans 3", "Helvetica Neue", Helvetica, sans-serif;
  color: var(--theme-main-text);
  background: linear-gradient(180deg, #f7f8fa 0%, #eef2f7 100%);
}

a {
  color: inherit;
}

.theme-main-container {
  width: min(1120px, 92vw);
  margin: 0 auto;
}

.theme-main-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(8px);
  background: color-mix(in srgb, var(--theme-main-bg) 88%, transparent);
  border-bottom: 1px solid var(--theme-main-line);
}

.theme-main-header .theme-main-container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 0;
}

.theme-main-brand {
  font-family: "Space Grotesk", "Segoe UI", sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  text-decoration: none;
  letter-spacing: 0.01em;
}

.theme-main-nav-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.theme-main-nav-item a {
  display: inline-block;
  padding: 0.45rem 0.8rem;
  border-radius: 999px;
  text-decoration: none;
  color: var(--theme-main-muted);
  transition: all 0.18s ease;
}

.theme-main-nav-item a:hover,
.theme-main-nav-item.is-active a {
  color: var(--theme-main-accent-contrast);
  background: var(--theme-main-accent);
}

.theme-main-content {
  padding: 2rem 0 3rem;
}

.theme-main-content .frame {
  background: var(--theme-main-surface);
  border: 1px solid var(--theme-main-line);
  border-radius: var(--theme-main-radius);
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.05);
  padding: clamp(1rem, 3vw, 2rem);
}

.theme-main-footer {
  border-top: 1px solid var(--theme-main-line);
  padding: 1.5rem 0 2rem;
  color: var(--theme-main-muted);
  font-size: 0.95rem;
}

.theme-main-footer p {
  margin: 0;
}

@media (max-width: 640px) {
  .theme-main-header .theme-main-container {
    align-items: flex-start;
  }

  .theme-main-nav-list {
    gap: 0.25rem;
  }

  .theme-main-nav-item a {
    padding: 0.4rem 0.7rem;
  }
}