/* ==========================================================================
   ToolWorld — Base / Reset / Typography
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

html, body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--duration-base) var(--ease), color var(--duration-base) var(--ease);
}

img, svg { display: block; max-width: 100%; }

h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; margin: 0 0 var(--space-3); letter-spacing: -0.01em; }
h1 { font-size: clamp(1.9rem, 1.5rem + 1.6vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 1.3rem + 0.9vw, 2rem); }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.05rem; }

p { margin: 0 0 var(--space-4); color: var(--color-text-muted); }
p:last-child { margin-bottom: 0; }

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

ul, ol { margin: 0 0 var(--space-4); padding-left: 1.3em; color: var(--color-text-muted); }
li { margin-bottom: var(--space-2); }

code, pre {
  font-family: var(--font-mono);
  font-size: 0.9em;
}
pre {
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  overflow-x: auto;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

button { cursor: pointer; }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: 4px;
}

.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;
  left: var(--space-3);
  top: -48px;
  background: var(--color-primary);
  color: var(--color-on-primary);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  z-index: 1000;
  transition: top var(--duration-base) var(--ease);
}
.skip-link:focus { top: var(--space-3); }

/* Layout helpers */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: var(--space-5);
}

.section { padding-block: var(--space-8); }
.section-tight { padding-block: var(--space-6); }

.stack { display: flex; flex-direction: column; }
.row { display: flex; align-items: center; }
.gap-1 { gap: var(--space-1); } .gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); } .gap-4 { gap: var(--space-4); }
.gap-5 { gap: var(--space-5); }

.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }
.text-sm { font-size: 0.875rem; }
.mt-0 { margin-top: 0 !important; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}

.visually-hidden-mobile {
  display: none;
}

@media (min-width: 640px) {
  .visually-hidden-mobile { display: initial; }
}

::selection {
  background: var(--color-primary);
  color: var(--color-on-primary);
}