/* ========================================
   CET Club Platform — Design System
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

:root {
  /* ---- Colour tokens ---- */
  --blue-50:  #eff6ff;
  --blue-100: #dbeafe;
  --blue-200: #bfdbfe;
  --blue-300: #93c5fd;
  --blue-400: #60a5fa;
  --blue-500: #3b82f6;
  --blue-600: #2563eb;
  --blue-700: #1d4ed8;
  --blue-800: #1e40af;
  --blue-900: #1e3a5f;

  --sky-400:  #38bdf8;
  --sky-500:  #0ea5e9;

  --slate-50:  #f8fafc;
  --slate-100: #f1f5f9;
  --slate-200: #e2e8f0;
  --slate-300: #cbd5e1;
  --slate-400: #94a3b8;
  --slate-500: #64748b;
  --slate-600: #475569;
  --slate-700: #334155;
  --slate-800: #1e293b;
  --slate-900: #0f172a;

  --white: #ffffff;
  --black: #000000;

  /* ---- Semantic tokens ---- */
  --color-primary:   var(--blue-600);
  --color-primary-hover: var(--blue-700);
  --color-accent:    var(--sky-500);
  --color-bg:        var(--slate-50);
  --color-surface:   var(--white);
  --color-text:      var(--slate-800);
  --color-text-secondary: var(--slate-500);
  --color-text-muted: var(--slate-400);
  --color-border:    var(--slate-200);
  --color-border-hover: var(--slate-300);

  /* ---- Gradients ---- */
  --gradient-primary: linear-gradient(135deg, var(--blue-600), var(--sky-500));
  --gradient-dark:    linear-gradient(135deg, var(--slate-900), var(--blue-900));
  --gradient-surface: linear-gradient(180deg, var(--white), var(--blue-50));
  --gradient-hero:    linear-gradient(160deg, #0f172a 0%, #1e3a5f 50%, #1d4ed8 100%);

  /* ---- Spacing ---- */
  --space-xs:   0.25rem;
  --space-sm:   0.5rem;
  --space-md:   1rem;
  --space-lg:   1.5rem;
  --space-xl:   2rem;
  --space-2xl:  3rem;
  --space-3xl:  4rem;
  --space-4xl:  6rem;

  /* ---- Radii ---- */
  --radius-sm:  6px;
  --radius-md:  10px;
  --radius-lg:  16px;
  --radius-xl:  24px;
  --radius-full: 9999px;

  /* ---- Shadows ---- */
  --shadow-xs:  0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:  0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg:  0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl:  0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
  --shadow-glow: 0 0 40px rgba(37,99,235,0.15);

  /* ---- Transition ---- */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);

  /* ---- Layout ---- */
  --max-width: 1200px;
  --nav-height: 72px;
}

/* ========================================
   Reset & Base
   ======================================== */

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
}

/* ---- Typography ---- */

h1, h2, h3, h4, h5, h6 {
  color: var(--slate-900);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3.25rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2rem); }
h3 { font-size: clamp(1.15rem, 2.5vw, 1.35rem); }

p {
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---- Links ---- */

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-hover);
  text-decoration: none;
}

/* ---- Images ---- */

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ---- Utility ---- */

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ---- Selection ---- */

::selection {
  background-color: var(--blue-200);
  color: var(--slate-900);
}