/* PERUSTYYLI (common to both themes) */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

.site-header,
.top-nav,
.layout,
.site-footer {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

.site-header {
  padding: 2.75rem 1.25rem 1.5rem;
}

.site-header h1 {
  margin: 0 0 0.3rem;
  font-size: clamp(2.1rem, 3vw, 2.6rem);
  letter-spacing: -0.03em;
}

.tagline {
  margin: 0;
  max-width: 38rem;
}

.top-nav {
  display: flex;
  gap: 0.75rem;
  padding-bottom: 1.1rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.8rem;
}

.top-nav a {
  font-size: 0.92rem;
  text-decoration: none;
  padding: 0.45rem 0.85rem;
  border-radius: 999px;
  transition: all 0.18s ease-out;
  border: 1px solid transparent;
}
.top-nav {
  display: flex;
  flex-wrap: wrap;          /* sallitaan rivinvaihto */
  justify-content: center;
  gap: 1rem;
  padding: 0.75rem 1rem 1.5rem;
}

.top-nav a {
  white-space: nowrap;      /* ei katkaista sanaa keskeltä */
  font-size: 0.95rem;
}
@media (max-width: 480px) {
  .top-nav {
    gap: 0.5rem;
  }

  .top-nav a {
    font-size: 0.85rem;
  }
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 2.5fr) minmax(0, 1.3fr);
  gap: 1.75rem;
  padding-bottom: 2.5rem;
}

.main-column,
.sidebar {
  border-radius: 16px;
  padding: 1.75rem 1.5rem;
}

.card {
  border-radius: 10px;
  padding: 1rem 1.1rem;
  margin-bottom: 0.75rem;
}

.muted {
  font-size: 0.9rem;
}

.site-footer {
  padding: 1.5rem 1.25rem 2.5rem;
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
  text-align: center;
}

/* ——————————————————————————————
   🌞 LIGHT THEME (Nordic Minimal)
—————————————————————————————— */
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f4f5f7;
    --bg-alt: #ffffff;
    --border: #dde2ea;
    --text: #111827;
    --text-muted: #6b7280;
    --accent: #2563eb;
    --accent-soft: #e0edff;
    --shadow: 0 10px 25px rgba(15, 23, 42, 0.08);
  }

  body {
    background: radial-gradient(circle at top, #e0ecff 0, #f4f5f7 40%, #eef1f6 100%);
    color: var(--text);
  }

  .main-column,
  .sidebar {
    background: var(--bg-alt);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
  }

  .top-nav a {
    color: var(--text-muted);
  }
  .top-nav a:hover {
    background: var(--accent-soft);
    color: var(--accent);
    border-color: var(--accent-soft);
  }

  a { color: var(--accent); }

  .card {
    background: linear-gradient(145deg, #ffffff, #f5f7fb);
    border: 1px solid var(--border);
  }

  .muted { color: var(--text-muted); }
}

/* ——————————————————————————————
   🌙 DARK THEME (AI / Futuristic)
—————————————————————————————— */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #050816;
    --bg-alt: #0b1020;
    --border: rgba(255,255,255,0.07);
    --text: #e5e7eb;
    --text-muted: #9ca3af;
    --accent: #60a5fa;
    --accent-soft: rgba(96,165,250,0.15);
    --shadow: 0 18px 40px rgba(0,0,0,0.6);
  }

  body {
    background: radial-gradient(circle at top, #1e2338 0, #050816 50%, #000 100%);
    color: var(--text);
  }

  .main-column,
  .sidebar {
    background: linear-gradient(145deg, #0f172aee, #111827ee);
    box-shadow: var(--shadow);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border);
  }

  .top-nav { border-color: rgba(255,255,255,0.12); }

  .top-nav a {
    color: var(--text-muted);
    background: rgba(15, 23, 42, 0.5);
  }
  .top-nav a:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(96,165,250,0.1);
  }

  a { color: var(--accent); }

  .card {
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.08);
    backdrop-filter: blur(6px);
  }

  .muted { color: var(--text-muted); }
}

/* ——————————————————————————————
   📱 RESPONSIVE
—————————————————————————————— */
@media (max-width: 800px) {
  .layout {
    grid-template-columns: minmax(0, 1fr);
  }
}
.button {
  display: inline-block;
  padding: 0.6rem 1.2rem;
  border-radius: 999px;
  text-decoration: none;
  border: 1px solid rgba(0,0,0,0.1);
  font-weight: 500;
  font-size: 0.95rem;
}

.button:hover {
  filter: brightness(0.96);
}