/* Erasmus-Helsinki Modern Skin
   - Light, friendly, high-contrast UI
   - WCAG 2.1 AA-focused
   - No external libs; Bootstrap remains as-is
*/

:root{
  --color-primary: #1E88E5;
  --color-primary-700: #1565C0;
  --color-accent: #FFB74D;
  --color-text: #212121;
  --color-muted: #455A64;
  --bg: #FFFFFF;
  --bg-soft: #FAFAFA;
  --border: #E0E0E0;

  --radius: 12px;
  --shadow-1: 0 2px 6px rgba(0,0,0,0.08);
  --shadow-2: 0 8px 24px rgba(0,0,0,0.12);

  --focus: 3px solid #1E88E5;
}

/* Base typography */
html { font-size: 100%; }
body {
  color: var(--color-text);
  background: var(--bg);
  line-height: 1.65;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
  text-rendering: optimizeLegibility;
}

p { max-width: 70ch; }
h1, h2, h3 { line-height: 1.25; font-weight: 700; }
h1 { font-size: clamp(2rem, 4vw, 3rem); }
h2 { font-size: clamp(1.5rem, 2.5vw, 2rem); margin-top: 1.5rem; }
h3 { font-size: clamp(1.125rem, 2vw, 1.35rem); }

/* Layout constraints */
.container { max-width: 1200px; }
section, .container .row { margin-bottom: 2rem; }

/* Navbar: sticky with clear hover/focus */
.navbar {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(255,255,255,0.98);
  border-bottom: 1px solid var(--border);
  transition: box-shadow .2s ease;
}
.navbar-scrolled { box-shadow: var(--shadow-1); }
.navbar-brand { font-weight: 700; color: var(--color-text); }
.navbar-brand:focus, .navbar-brand:hover { color: var(--color-primary); }
.navbar-nav .nav-link { font-weight: 600; padding: .5rem .75rem; }
.navbar-nav .nav-link:hover { color: var(--color-primary); }
.navbar-nav .nav-link.active { color: var(--color-primary); }

/* Skip link */
.skip-link {
  position: absolute; left: -999px; top: auto; width: 1px; height: 1px; overflow: hidden;
}
.skip-link:focus {
  left: 1rem; top: 1rem; width: auto; height: auto;
  background: var(--color-primary); color: #fff; padding: .5rem .75rem;
  border-radius: 6px; outline: none;
}

/* Hero with overlay for contrast */
.hero {
  min-height: 56vh;
  display: grid; place-items: center;
  text-align: center; color: #fff;
  position: relative;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,.45), rgba(0,0,0,.35));
}
.hero .hero-content { position: relative; padding: 2rem; }
.hero h1, .hero p { text-shadow: 0 2px 6px rgba(0,0,0,.35); }

/* Cards */
.card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
}
.card:hover { box-shadow: var(--shadow-2); transform: translateY(-2px); }
.card img { border-top-left-radius: var(--radius); border-top-right-radius: var(--radius); }

/* Buttons */
.btn-primary, .btn-outline-primary, a.btn.btn-outline-primary {
  --btn-bg: var(--color-primary);
  --btn-bg-hover: var(--color-primary-700);
  --btn-text: #fff;
  border: 2px solid var(--color-primary);
  color: var(--color-primary);
  background: transparent;
  font-weight: 700;
}
.btn-primary { background: var(--btn-bg); color: #fff; border-color: var(--btn-bg); }
.btn-primary:hover, .btn-primary:focus { background: var(--btn-bg-hover); border-color: var(--btn-bg-hover); color: #fff; }
.btn-outline-primary:hover, .btn-outline-primary:focus { background: var(--btn-bg); color: #fff; }

/* Accent tag */
.badge-accent { background: var(--color-accent); color: #4E342E; font-weight: 700; }

/* Footer */
.footer { background: var(--color-text); color: #fff; }
.footer a { color: #fff; text-decoration: underline; }
.footer a:focus { outline: var(--focus); outline-offset: 2px; }

/* Focus visibility for a11y */
:where(a, button, [role="button"], .nav-link, .card):focus-visible {
  outline: var(--focus);
  outline-offset: 2px;
  border-radius: 8px;
}

/* Motion sensitivity */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}

/* Utility */
.prose { max-width: 70ch; }
.text-muted-strong { color: var(--color-muted); }

/* Media tweaks */
@media (max-width: 768px) {
  .hero { min-height: 44vh; }
}