/* =====================================================
   Helix Therapeutics — Main CSS
   Variables · Reset · Typography · Layout Utilities
   ===================================================== */

/* ---- Custom Properties ---- */
:root {
  --color-primary:      #1B3A6B;
  --color-primary-dark: #122A50;
  --color-primary-light:#2563EB;
  --color-accent:       #0066CC;
  --color-white:        #FFFFFF;
  --color-off-white:    #F5F7FA;
  --color-gray-100:     #F0F4F8;
  --color-gray-200:     #E2E8F0;
  --color-gray-400:     #94A3B8;
  --color-gray-600:     #64748B;
  --color-gray-800:     #334155;
  --color-text:         #1A1A2E;
  --color-border:       #E2E8F0;

  --font-heading: 'Poppins', sans-serif;
  --font-body:    'Inter', sans-serif;

  --shadow-sm:  0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
  --shadow-md:  0 4px 6px rgba(0,0,0,.07), 0 2px 4px rgba(0,0,0,.06);
  --shadow-lg:  0 10px 15px rgba(0,0,0,.1), 0 4px 6px rgba(0,0,0,.05);
  --shadow-xl:  0 20px 25px rgba(0,0,0,.1), 0 10px 10px rgba(0,0,0,.04);

  --radius-sm:  4px;
  --radius-md:  8px;
  --radius-lg:  12px;
  --radius-xl:  20px;

  --transition: 220ms ease;

  --container-max: 1200px;
  --header-h:      80px;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a  { color: var(--color-accent); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-primary); }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ---- Typography ---- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.25;
  color: var(--color-primary);
}
h1 { font-size: clamp(2rem, 4vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.125rem; }
h5 { font-size: 1rem; }

p { margin-bottom: 1rem; color: var(--color-gray-800); }
p:last-child { margin-bottom: 0; }

.lead { font-size: 1.125rem; color: var(--color-gray-600); line-height: 1.75; }

/* ---- Layout ---- */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
}

section { padding: 5rem 0; }

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}
.section-header h2 { margin-bottom: .75rem; }
.section-header p { max-width: 600px; margin: 0 auto; }

/* ---- Section Label ---- */
.section-label {
  display: inline-block;
  font-size: .8rem;
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: .75rem;
}

/* ---- Grid Utilities ---- */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 2rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 2rem; }

/* ---- Flex Utilities ---- */
.flex        { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between{ display: flex; align-items: center; justify-content: space-between; }
.flex-gap    { gap: 1rem; }

/* ---- Spacing Utilities ---- */
.mt-1 { margin-top: .5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: .5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

/* ---- Backgrounds ---- */
.bg-light   { background: var(--color-gray-100); }
.bg-primary { background: var(--color-primary); color: var(--color-white); }
.bg-primary h1, .bg-primary h2, .bg-primary h3, .bg-primary h4,
.bg-primary p { color: var(--color-white); }

/* ---- Breadcrumb ---- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-size: .875rem;
  color: var(--color-gray-600);
  padding: 1rem 0;
}
.breadcrumb a { color: var(--color-gray-600); }
.breadcrumb a:hover { color: var(--color-primary); }
.breadcrumb .sep { color: var(--color-gray-400); }
.breadcrumb .current { color: var(--color-primary); font-weight: 500; }

.breadcrumb-bar {
  background: var(--color-gray-100);
  border-bottom: 1px solid var(--color-border);
}

/* ---- Page Hero (inner pages) ---- */
.page-hero {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: var(--color-white);
  padding: 4rem 0;
  text-align: center;
}
.page-hero h1 { color: var(--color-white); margin-bottom: .75rem; }
.page-hero p  { color: rgba(255,255,255,.8); font-size: 1.125rem; max-width: 600px; margin: 0 auto; }

/* ---- Divider ---- */
.divider {
  width: 60px;
  height: 4px;
  background: var(--color-accent);
  border-radius: 2px;
  margin: 1rem 0 1.5rem;
}
.divider-center { margin: 1rem auto 1.5rem; }

/* ---- Responsive ---- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  section { padding: 3.5rem 0; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .grid-4 { grid-template-columns: 1fr; }
}