/* ============================================================
   Attic Philosophy Tutoring — Design Tokens
   Warm, scholarly, typographically precise.
   ============================================================ */

:root {
  /* ---------- Colour ---------- */
  --bone:        oklch(0.975 0.005 85);    /* page bg — warm off-white */
  --bone-2:      oklch(0.955 0.007 80);    /* card surface */
  --bone-3:      oklch(0.925 0.009 80);    /* inset / hairline panels */

  --ink:         oklch(0.22 0.012 60);     /* primary text */
  --ink-2:       oklch(0.34 0.012 60);     /* secondary text */
  --ink-3:       oklch(0.52 0.010 65);     /* tertiary / captions */
  --ink-4:       oklch(0.74 0.008 70);     /* hairlines, disabled */

  /* Single accent — deep teal, used sparingly */
  --teal:        oklch(0.45 0.07 200);
  --teal-deep:   oklch(0.38 0.075 205);
  --teal-soft:   oklch(0.93 0.025 200);

  /* ---------- Type ---------- */
  --font-display: "Newsreader", "Cormorant Garamond", Georgia, serif;
  --font-sans:    "Geist", "Söhne", "Inter", system-ui, -apple-system, "Helvetica Neue", sans-serif;
  --font-mono:    "Geist Mono", "JetBrains Mono", "SF Mono", ui-monospace, monospace;

  /* ---------- Spacing (8-pt base) ---------- */
  --s-1:  4px;
  --s-2:  8px;
  --s-3:  12px;
  --s-4:  16px;
  --s-5:  24px;
  --s-6:  32px;
  --s-7:  48px;
  --s-8:  64px;
  --s-9:  96px;
  --s-10: 128px;
  --s-11: 160px;

  /* ---------- Radii ---------- */
  --r-sm:   4px;
  --r-md:   8px;
  --r-lg:   14px;
  --r-xl:   22px;
  --r-pill: 999px;

  /* ---------- Elevation ---------- */
  --sh-1: 0 1px 2px rgba(28, 24, 20, 0.04), 0 1px 1px rgba(28, 24, 20, 0.03);
  --sh-2: 0 8px 24px rgba(28, 24, 20, 0.06), 0 2px 4px rgba(28, 24, 20, 0.04);
  --sh-3: 0 24px 60px rgba(28, 24, 20, 0.10), 0 6px 12px rgba(28, 24, 20, 0.05);

  /* ---------- Layout ---------- */
  --container:      1180px;
  --container-wide: 1320px;
  --gutter:         clamp(20px, 4vw, 48px);
}

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

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

html { scroll-behavior: smooth; scroll-padding-top: 88px; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bone);
  color: var(--ink);
  font-family: var(--font-sans);
  font-feature-settings: "kern", "ss01", "cv11";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-size: 16px;
  line-height: 1.5;
  letter-spacing: -0.01em;
}

img { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

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

.display-xl {
  font-family: var(--font-display);
  font-weight: 360;
  font-size: clamp(44px, 7.4vw, 96px);
  line-height: 1.02;
  letter-spacing: -0.025em;
}
.display-xl em { font-style: italic; font-weight: 340; color: var(--teal-deep); }

.display-lg {
  font-family: var(--font-display);
  font-weight: 380;
  font-size: clamp(34px, 4.4vw, 56px);
  line-height: 1.04;
  letter-spacing: -0.022em;
}
.display-lg em { font-style: italic; font-weight: 360; color: var(--teal-deep); }

.heading-md {
  font-family: var(--font-display);
  font-weight: 420;
  font-size: clamp(24px, 2.6vw, 32px);
  line-height: 1.12;
  letter-spacing: -0.018em;
}

.heading-sm {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 20px;
  line-height: 1.25;
  letter-spacing: -0.015em;
}

.body-lg {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 19px;
  line-height: 1.6;
  letter-spacing: -0.012em;
  color: var(--ink-2);
}

.body-md {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  letter-spacing: -0.005em;
  color: var(--ink-2);
}

.body-sm {
  font-family: var(--font-sans);
  font-weight: 420;
  font-size: 14px;
  line-height: 1.55;
  letter-spacing: -0.003em;
  color: var(--ink-3);
}

.mono-label {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 12px;
  line-height: 1.2;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-2);
}

.mono-label-lg {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 13px;
  line-height: 1.3;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-2);
}

.section-marker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.section-marker::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--teal);
  display: inline-block;
}

/* ============================================================
   Buttons
   ============================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  border-radius: var(--r-pill);
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 15px;
  letter-spacing: -0.005em;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
  white-space: nowrap;
  line-height: 1;
}
.btn:focus-visible {
  outline: 1.5px dashed var(--ink);
  outline-offset: 3px;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--ink {
  background: var(--ink);
  color: var(--bone);
}
.btn--ink:hover { background: #000; }

.btn--teal {
  background: var(--teal-deep);
  color: var(--bone);
}
.btn--teal:hover { background: oklch(0.32 0.08 205); }

.btn--ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
}
.btn--ghost:hover { background: var(--ink); color: var(--bone); }

.btn--lg { padding: 18px 30px; font-size: 16px; }
.btn--sm { padding: 10px 16px; font-size: 13px; }

/* Inline arrow */
.btn .arrow {
  display: inline-block;
  width: 16px; height: 16px;
  transition: transform 0.2s ease;
}
.btn:hover .arrow { transform: translateX(3px); }

/* ============================================================
   Utilities
   ============================================================ */

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

.hairline { height: 1px; background: var(--ink-4); opacity: 0.35; }

.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;
}