/* ==========================================================================
   Base Styles & Reset - NIOSA Academy
   ========================================================================== */

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

html {
  font-family: var(--na-font);
  font-size: 16px;
  line-height: var(--na-lh-body);
  color: var(--na-text-body);
  background-color: var(--na-bg);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body.na-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--na-bg);
  overflow-x: clip;
  position: relative;
}

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

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--na-dur-micro) var(--na-ease-out);
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
  background: transparent;
  border: none;
  outline: none;
}

button {
  cursor: pointer;
  user-select: none;
}

ul, ol {
  list-style: none;
}

/* Accessibility: Focus outlines */
:focus-visible {
  outline: 3px solid rgba(30, 136, 229, 0.6);
  outline-offset: 3px;
}

/* Skip link */
.na-skip-link {
  position: absolute;
  top: -100px;
  left: 20px;
  padding: 12px 20px;
  background: var(--na-brand);
  color: var(--na-text-inverse);
  font-weight: 700;
  border-radius: var(--na-radius-md);
  z-index: 99999;
  transition: top var(--na-dur-base) var(--na-ease-spring);
}
.na-skip-link:focus {
  top: 20px;
}

/* Scroll progress */
.na-scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: var(--na-grad-progress);
  z-index: var(--na-z-progress);
  transition: width 50ms linear;
}

/* Layout Container */
.na-container {
  width: 100%;
  max-width: var(--na-container);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--na-gutter);
  padding-right: var(--na-gutter);
  box-sizing: border-box;
}

@media (max-width: 991px) {
  :root {
    --na-gutter: 24px;
  }
}

@media (max-width: 640px) {
  :root {
    --na-gutter: 18px;
    --na-section-y: 44px;
    --na-grid-gap: 16px;
  }
}

@media (max-width: 480px) {
  :root {
    --na-gutter: 16px;
  }
}

/* Typography Scale */
h1, h2, h3, h4, h5, h6 {
  color: var(--na-text-main);
  font-weight: 800;
  line-height: var(--na-lh-tight);
  letter-spacing: var(--na-tracking-tight);
}

h1 { font-size: clamp(1.75rem, 3.2vw, 2.35rem); }
h2 { font-size: clamp(1.35rem, 2.2vw, 1.85rem); }
h3 { font-size: clamp(1.15rem, 1.6vw, 1.35rem); font-weight: 700; }
h4 { font-size: 1.1rem; font-weight: 700; }

p {
  color: var(--na-text-body);
  line-height: var(--na-lh-body);
}

.na-text-gradient {
  background: var(--na-grad-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  color: var(--na-brand);
}

.na-text-muted { color: var(--na-text-muted); }
.na-text-brand { color: var(--na-brand); }
.na-text-accent { color: var(--na-accent); }

/* Section Header */
.na-section-header {
  margin-bottom: 32px;
}
.na-section-header.text-center {
  text-align: center;
}
.na-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  background: var(--na-brand-light);
  color: var(--na-brand);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--na-radius-full);
  margin-bottom: 10px;
}
.na-section-title {
  font-size: clamp(1.35rem, 2.2vw, 1.85rem);
  margin-bottom: 10px;
}
.na-section-desc {
  max-width: 620px;
  font-size: 0.95rem;
  color: var(--na-text-muted);
}
.na-section-header.text-center .na-section-desc {
  margin-left: auto;
  margin-right: auto;
}