/* === Reset & Base === */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-relaxed);
  color: var(--color-gray-800);
  background-color: var(--color-white);
  overflow-x: hidden;
}

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

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

a:hover {
  color: var(--color-primary);
}

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  outline: none;
}

/* === Typography === */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-dark);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--space-4);
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-accent { color: var(--color-accent); }
.text-muted { color: var(--color-gray-500); }
.text-white { color: var(--color-white); }

.font-medium { font-weight: var(--font-weight-medium); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

/* === Container === */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.container-narrow {
  max-width: 960px;
}

/* === Section === */
.section {
  padding-top: var(--space-20);
  padding-bottom: var(--space-20);
}

.section-sm {
  padding-top: var(--space-12);
  padding-bottom: var(--space-12);
}

.section-dark {
  background-color: var(--color-dark);
  color: var(--color-gray-200);
}

.section-dark h1,
.section-dark h2,
.section-dark h3,
.section-dark h4,
.section-dark h5,
.section-dark h6 {
  color: var(--color-white);
}

.section-light {
  background-color: var(--color-gray-50);
}

/* === Grid === */
.row {
  display: flex;
  flex-wrap: wrap;
  margin-left: calc(var(--space-4) * -1);
  margin-right: calc(var(--space-4) * -1);
}

.col {
  flex: 1 0 0%;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

.col-6 { flex: 0 0 50%; max-width: 50%; }
.col-4 { flex: 0 0 33.333%; max-width: 33.333%; }
.col-3 { flex: 0 0 25%; max-width: 25%; }
.col-12 { flex: 0 0 100%; max-width: 100%; }

/* === Visibility === */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* === Screen Reader Only === */
.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;
}