:root {
  --background: 210 33% 98%;
  --foreground: 217 48% 20%;
  --card: 0 0% 100%;
  --card-foreground: 217 48% 20%;
  --muted: 210 20% 95%;
  --muted-foreground: 216 14% 40%;
  --primary: 217 48% 20%;
  --primary-foreground: 0 0% 100%;
  --accent: 207 55% 40%;
  --accent-foreground: 0 0% 100%;
  --border: 214 32% 91%;
  --input: 214 32% 91%;
  --destructive: 0 72% 51%;
  --success: 160 84% 29%;
  --warning: 37 92% 44%;
  --navy: 217 48% 20%;
  --blue: 207 55% 40%;
  --radius: 0.625rem;
}

.dark {
  --background: 220 20% 8%;
  --foreground: 210 33% 95%;
  --card: 220 18% 12%;
  --card-foreground: 210 33% 95%;
  --muted: 220 16% 16%;
  --muted-foreground: 216 14% 65%;
  --primary: 210 33% 95%;
  --primary-foreground: 220 20% 8%;
  --accent: 207 55% 50%;
  --accent-foreground: 0 0% 100%;
  --border: 220 16% 20%;
  --input: 220 16% 20%;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Plus Jakarta Sans', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: hsl(var(--background));
  color: hsl(var(--foreground));
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  margin: 0;
}

.text-gradient {
  background: linear-gradient(135deg, hsl(var(--navy)) 0%, hsl(var(--blue)) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.dark .text-gradient {
  background: linear-gradient(135deg, hsl(210 33% 95%) 0%, hsl(207 55% 65%) 100%);
  -webkit-background-clip: text;
  background-clip: text;
}

.bg-gradient-accent {
  background: linear-gradient(135deg, hsl(var(--navy)) 0%, hsl(var(--blue)) 100%);
}

.bg-gradient-accent-light {
  background: linear-gradient(135deg, hsla(var(--navy) / 0.05) 0%, hsla(var(--blue) / 0.05) 100%);
}

.dark .bg-gradient-accent-light {
  background: linear-gradient(135deg, hsla(var(--blue) / 0.08) 0%, hsla(var(--navy) / 0.08) 100%);
}

/* Accessible focus ring */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid hsl(var(--accent));
  outline-offset: 2px;
  border-radius: 4px;
}

/* Skip link */
.skip-link {
  position: absolute;
  left: -9999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.skip-link:focus {
  position: fixed;
  top: 12px;
  left: 12px;
  width: auto;
  height: auto;
  padding: 8px 16px;
  background: hsl(var(--accent));
  color: white;
  border-radius: 4px;
  font-weight: 600;
  z-index: 9999;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: hsl(var(--muted));
}
::-webkit-scrollbar-thumb {
  background: hsl(var(--muted-foreground) / 0.4);
  border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
  background: hsl(var(--muted-foreground) / 0.6);
}

/* Card helper */
.as-card {
  background: hsl(var(--card));
  color: hsl(var(--card-foreground));
  border: 1px solid hsl(var(--border));
  border-radius: var(--radius);
}

/* Course carousel — hide scrollbar on webkit + firefox */
.course-carousel { scrollbar-width: thin; }
.course-carousel::-webkit-scrollbar { height: 8px; }
.course-carousel::-webkit-scrollbar-thumb { background: hsl(var(--border)); border-radius: 9999px; }
.course-carousel::-webkit-scrollbar-track { background: transparent; }