/* ============================================================
   The Eduverse · design tokens, typography, layout primitives
   ============================================================ */

:root {
  /* Brand */
  --color-navy:        #0E2A6E;
  --color-navy-deep:   #081A47;
  --color-navy-soft:   #1B3D8F;
  --color-red:         #C8102E;
  --color-red-deep:    #9C0B23;
  --color-red-soft:    #E03A52;

  /* Neutrals */
  --color-ink:         #0B1530;
  --color-graphite:    #2A3346;
  --color-slate:       #5C6478;
  --color-mute:        #8A92A6;
  --color-line:        #E4E6EC;
  --color-line-soft:   #F0F1F4;
  --color-paper:       #FAFAF7;
  --color-cream:       #F4F1EA;
  --color-white:       #FFFFFF;

  /* Surface */
  --bg:                var(--color-paper);
  --bg-elevated:       var(--color-white);
  --bg-deep:           var(--color-navy-deep);

  /* Type */
  --font-serif: "Fraunces", "Times New Roman", Georgia, serif;
  --font-sans:  "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  /* Fluid type scale */
  --step--2: clamp(0.75rem, 0.72rem + 0.15vw, 0.82rem);
  --step--1: clamp(0.875rem, 0.84rem + 0.18vw, 0.95rem);
  --step-0:  clamp(1rem, 0.96rem + 0.2vw, 1.075rem);
  --step-1:  clamp(1.125rem, 1.07rem + 0.28vw, 1.25rem);
  --step-2:  clamp(1.35rem, 1.25rem + 0.5vw, 1.6rem);
  --step-3:  clamp(1.65rem, 1.5rem + 0.75vw, 2.05rem);
  --step-4:  clamp(2rem, 1.75rem + 1.25vw, 2.75rem);
  --step-5:  clamp(2.5rem, 2.05rem + 2.25vw, 3.85rem);
  --step-6:  clamp(3rem, 2.4rem + 3vw, 5rem);
  --step-7:  clamp(3.75rem, 2.8rem + 4.75vw, 7rem);

  /* Space scale */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.5rem;
  --space-6:  2rem;
  --space-7:  3rem;
  --space-8:  4.5rem;
  --space-9:  6.5rem;
  --space-10: 9rem;

  /* Layout */
  --container:        72rem;
  --container-wide:   84rem;
  --container-narrow: 56rem;
  --gutter: clamp(1.25rem, 4vw, 3rem);

  /* Radii */
  --radius-sm: 4px;
  --radius:    8px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-pill: 999px;

  /* Shadow */
  --shadow-1: 0 1px 2px rgba(11, 21, 48, .06), 0 1px 1px rgba(11, 21, 48, .04);
  --shadow-2: 0 6px 24px -8px rgba(11, 21, 48, .12), 0 2px 6px rgba(11, 21, 48, .06);
  --shadow-3: 0 30px 60px -25px rgba(11, 21, 48, .25), 0 8px 20px -10px rgba(11, 21, 48, .12);

  /* Motion */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur-1: 180ms;
  --dur-2: 320ms;
  --dur-3: 600ms;
}

/* ============================================================
   Base
   ============================================================ */

html { scroll-padding-top: 92px; }

body {
  font-family: var(--font-sans);
  font-size: var(--step-0);
  color: var(--color-ink);
  background: var(--bg);
  font-feature-settings: "ss01", "cv11";
}

p { color: var(--color-graphite); max-width: 70ch; }
p + p { margin-top: var(--space-4); }

a { color: var(--color-navy); transition: color var(--dur-1) var(--ease-out); }
a:hover { color: var(--color-red); }

strong, b { font-weight: 600; color: var(--color-ink); }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--color-line-soft); }
::-webkit-scrollbar-thumb { background: var(--color-line); border-radius: 99px; }
::-webkit-scrollbar-thumb:hover { background: var(--color-mute); }

/* ============================================================
   Typography
   ============================================================ */

.h1, .h2, .h3, .h4 {
  font-family: var(--font-serif);
  color: var(--color-ink);
  letter-spacing: -0.015em;
  font-weight: 600;
}

.h-display {
  font-family: var(--font-serif);
  font-size: var(--step-7);
  line-height: 0.98;
  letter-spacing: -0.03em;
  font-weight: 700;
  color: var(--color-ink);
}

.h1 { font-size: var(--step-6); line-height: 1.05; letter-spacing: -0.025em; font-weight: 700; }
.h2 { font-size: var(--step-5); line-height: 1.08; letter-spacing: -0.022em; font-weight: 700; }
.h3 { font-size: var(--step-3); line-height: 1.18; }
.h4 { font-size: var(--step-2); line-height: 1.25; }

.eyebrow {
  font-family: var(--font-sans);
  font-size: var(--step--2);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--color-red);
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
}
.eyebrow::before {
  content: "";
  display: inline-block;
  width: 28px;
  height: 1px;
  background: currentColor;
}

.lead {
  font-family: var(--font-serif);
  font-size: var(--step-2);
  line-height: 1.4;
  color: var(--color-graphite);
  font-weight: 400;
  letter-spacing: -0.005em;
  max-width: 56ch;
}

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

/* Decorative serif "drop" character used on big sections */
.dropcap::first-letter {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 4.6em;
  float: left;
  line-height: 0.85;
  padding: 0.05em 0.12em 0 0;
  color: var(--color-red);
}

/* ============================================================
   Layout primitives
   ============================================================ */

.container        { width: 100%; max-width: var(--container); margin-inline: auto; padding-inline: var(--gutter); }
.container-wide   { width: 100%; max-width: var(--container-wide); margin-inline: auto; padding-inline: var(--gutter); }
.container-narrow { width: 100%; max-width: var(--container-narrow); margin-inline: auto; padding-inline: var(--gutter); }

.section { padding-block: var(--space-9); }
.section--tight { padding-block: var(--space-7); }
.section--loose { padding-block: var(--space-10); }

.section--navy { background: var(--color-navy); color: var(--color-white); }
.section--navy p, .section--navy .lead { color: rgba(255,255,255,.85); }
.section--navy .h1, .section--navy .h2, .section--navy .h3, .section--navy .h4 { color: var(--color-white); }
.section--navy .eyebrow { color: #FFB3BB; }

.section--ink  { background: var(--color-ink); color: var(--color-white); }
.section--ink p { color: rgba(255,255,255,.78); }
.section--ink .h1, .section--ink .h2, .section--ink .h3 { color: var(--color-white); }

.section--cream { background: var(--color-cream); }
.section--paper { background: var(--color-paper); }

.grid { display: grid; gap: var(--space-6); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

.flex { display: flex; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.flex-wrap { display: flex; flex-wrap: wrap; gap: var(--space-4); }

.stack > * + * { margin-top: var(--space-4); }
.stack-lg > * + * { margin-top: var(--space-6); }
.stack-xl > * + * { margin-top: var(--space-7); }

/* Visually hidden */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.skip-link { position: absolute; top: -100px; left: 0; padding: var(--space-3) var(--space-5); background: var(--color-navy); color: var(--color-white); z-index: 999; }
.skip-link:focus { top: 0; }

/* ============================================================
   Reveal-on-scroll
   ============================================================ */

[data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity var(--dur-3) var(--ease-out), transform var(--dur-3) var(--ease-out);
  will-change: opacity, transform;
}
[data-reveal].is-visible { opacity: 1; transform: none; }
[data-reveal-delay="1"] { transition-delay: 80ms; }
[data-reveal-delay="2"] { transition-delay: 160ms; }
[data-reveal-delay="3"] { transition-delay: 240ms; }
[data-reveal-delay="4"] { transition-delay: 320ms; }