/* ============================================================
   BSA Design Tokens — Warm, honest, trades-inspired palette
   ============================================================ */

:root {
  /* Type Scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Fonts */
  --font-display: 'Cabinet Grotesk', 'Arial Black', sans-serif;
  --font-body: 'Satoshi', 'Helvetica Neue', sans-serif;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
}

/* LIGHT MODE — Warm cream & copper/steel blue */
:root, [data-theme="light"] {
  --color-bg:             #faf8f5;
  --color-surface:        #f4f1ec;
  --color-surface-2:      #ede9e2;
  --color-divider:        #d9d3c9;
  --color-border:         #c9c1b5;
  --color-text:           #1c1a16;
  --color-text-muted:     #6b6560;
  --color-text-faint:     #a39d96;
  --color-text-inverse:   #faf8f5;
  --color-primary:        #b45309;
  --color-primary-hover:  #92400e;
  --color-primary-active: #78350f;
  --color-primary-light:  #fef3c7;
  --color-accent:         #1e3a5f;
  --color-accent-light:   #e8eef5;

  --shadow-sm: 0 1px 2px rgba(28, 26, 22, 0.06);
  --shadow-md: 0 4px 12px rgba(28, 26, 22, 0.08);
  --shadow-lg: 0 12px 32px rgba(28, 26, 22, 0.12);
}

/* DARK MODE */
[data-theme="dark"] {
  --color-bg:             #141210;
  --color-surface:        #1c1a17;
  --color-surface-2:      #242119;
  --color-divider:        #302c25;
  --color-border:         #3d3830;
  --color-text:           #e8e4de;
  --color-text-muted:     #9c968e;
  --color-text-faint:     #5c5750;
  --color-text-inverse:   #141210;
  --color-primary:        #f59e0b;
  --color-primary-hover:  #d97706;
  --color-primary-active: #b45309;
  --color-primary-light:  #342a14;
  --color-accent:         #7db4e0;
  --color-accent-light:   #1a2a3e;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.4);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg:             #141210;
    --color-surface:        #1c1a17;
    --color-surface-2:      #242119;
    --color-divider:        #302c25;
    --color-border:         #3d3830;
    --color-text:           #e8e4de;
    --color-text-muted:     #9c968e;
    --color-text-faint:     #5c5750;
    --color-text-inverse:   #141210;
    --color-primary:        #f59e0b;
    --color-primary-hover:  #d97706;
    --color-primary-active: #b45309;
    --color-primary-light:  #342a14;
    --color-accent:         #7db4e0;
    --color-accent-light:   #1a2a3e;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.4);
  }
}

/* ============================================================
   Components
   ============================================================ */

/* -- Skip link -- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  z-index: 100;
}
.skip-link:focus { left: var(--space-4); }

/* -- Header -- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--color-bg) 92%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-divider);
  transition: box-shadow 0.3s ease;
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }

.header-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding: var(--space-3) var(--space-4);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.logo-group {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}
.logo-group:hover { color: var(--color-primary); }

.logo-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.2;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.logo-text span { display: block; }
.logo-text .build { color: var(--color-primary); }

/* Desktop nav */
.main-nav { display: flex; align-items: center; gap: var(--space-6); }
.main-nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  text-decoration: none;
  color: var(--color-text-muted);
  padding: var(--space-1) 0;
  position: relative;
}
.main-nav a:hover { color: var(--color-text); }
.main-nav a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width 0.3s ease;
}
.main-nav a:hover::after { width: 100%; }

.theme-toggle {
  padding: var(--space-2);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
}
.theme-toggle:hover {
  background: var(--color-surface);
  color: var(--color-text);
}

/* Mobile hamburger */
.mobile-toggle {
  display: none;
  padding: var(--space-2);
  color: var(--color-text);
}
.mobile-toggle svg { width: 24px; height: 24px; }

@media (max-width: 768px) {
  .main-nav { display: none; }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-divider);
    padding: var(--space-4);
    gap: var(--space-4);
    box-shadow: var(--shadow-md);
  }
  .mobile-toggle { display: block; }
}

/* -- Container -- */
.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-4);
}
.container--narrow { max-width: var(--content-default); }

/* -- Section spacing -- */
.section {
  padding-block: clamp(var(--space-12), 8vw, var(--space-24));
}

/* -- Hero -- */
.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to right,
    rgba(20, 18, 16, 0.88) 0%,
    rgba(20, 18, 16, 0.7) 50%,
    rgba(20, 18, 16, 0.3) 100%
  );
}
.hero-content {
  position: relative;
  z-index: 1;
  max-width: 640px;
  padding: var(--space-16) var(--space-4);
}
@media (min-width: 768px) {
  .hero-content { padding: var(--space-20) var(--space-8); }
}

.hero-tag {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}
[data-theme="dark"] .hero-tag,
:root:not([data-theme]) .hero-tag { color: #f59e0b; }

.hero h1 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
  color: #faf8f5;
  margin-bottom: var(--space-4);
  line-height: 1.08;
}

.hero-sub {
  font-size: var(--text-base);
  color: #d4cfc8;
  line-height: 1.65;
  margin-bottom: var(--space-8);
}

.hero-ctas { display: flex; flex-wrap: wrap; gap: var(--space-3); }

/* -- Buttons -- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  text-decoration: none;
  cursor: pointer;
  border: none;
  min-height: 44px;
}
.btn-primary {
  background: var(--color-primary);
  color: #faf8f5;
}
.btn-primary:hover { background: var(--color-primary-hover); }
.btn-primary:active { background: var(--color-primary-active); }

.btn-outline {
  background: transparent;
  color: #faf8f5;
  border: 1px solid rgba(250, 248, 245, 0.3);
}
.btn-outline:hover {
  background: rgba(250, 248, 245, 0.08);
  border-color: rgba(250, 248, 245, 0.5);
}

/* Buttons in non-hero context */
.section .btn-outline {
  color: var(--color-text);
  border-color: var(--color-border);
}
.section .btn-outline:hover {
  background: var(--color-surface);
  border-color: var(--color-text-muted);
  color: var(--color-text);
}

/* -- Stats bar -- */
.stats-bar {
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
  border-bottom: 1px solid var(--color-divider);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
  padding-block: var(--space-8);
  text-align: center;
}
.stat-number {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
  margin-bottom: var(--space-1);
}
.stat-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 500;
}
@media (max-width: 640px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: var(--space-6); }
}

/* -- Two-column feature -- */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(var(--space-8), 5vw, var(--space-16));
  align-items: center;
}
.two-col--reverse .two-col-media { order: -1; }
@media (max-width: 768px) {
  .two-col { grid-template-columns: 1fr; }
  .two-col--reverse .two-col-media { order: 0; }
}

.two-col-content h2 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}
.two-col-content p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.7;
}
.two-col-content p:last-child { margin-bottom: 0; }
.two-col-media img {
  border-radius: var(--radius-lg);
  width: 100%;
  aspect-ratio: 4/3;
  object-fit: cover;
  box-shadow: var(--shadow-md);
}

/* -- Section headers -- */
.section-eyebrow {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}
.section-heading {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}
.section-desc {
  color: var(--color-text-muted);
  max-width: 60ch;
  line-height: 1.7;
}

/* -- Curriculum cards -- */
.curriculum-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
  margin-top: var(--space-8);
}
@media (max-width: 640px) {
  .curriculum-grid { grid-template-columns: 1fr; }
}

.curr-card {
  background: var(--color-surface);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
}
.curr-card-icon {
  width: 40px;
  height: 40px;
  margin-bottom: var(--space-4);
  color: var(--color-primary);
}
.curr-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}
.curr-card ul {
  list-style: none;
  padding: 0;
}
.curr-card li {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  padding: var(--space-1) 0;
  padding-left: var(--space-5);
  position: relative;
  line-height: 1.5;
}
.curr-card li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  opacity: 0.6;
}

/* -- Comparison section -- */
.comparison {
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
  border-bottom: 1px solid var(--color-divider);
}
.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
  margin-top: var(--space-8);
}
@media (max-width: 640px) {
  .comparison-grid { grid-template-columns: 1fr; }
}
.comp-card {
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-divider);
}
.comp-card--other { background: var(--color-bg); }
.comp-card--bsa {
  background: var(--color-primary-light);
  border-color: var(--color-primary);
}
.comp-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-4);
  color: var(--color-text);
}
.comp-card li {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  padding: var(--space-2) 0;
  padding-left: var(--space-5);
  position: relative;
  line-height: 1.5;
}
.comp-card--other li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: var(--color-text-faint);
}
.comp-card--bsa li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-weight: 700;
}

/* -- Donor section -- */
.donor-highlights {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  margin-top: var(--space-8);
}
@media (max-width: 640px) {
  .donor-highlights { grid-template-columns: 1fr; }
}
.donor-card {
  text-align: center;
  padding: var(--space-6);
  background: var(--color-surface);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
}
.donor-card-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto var(--space-4);
  color: var(--color-primary);
}
.donor-card h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}
.donor-card p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-inline: auto;
}

/* -- CTA banner -- */
.cta-banner {
  background: var(--color-accent);
  color: #faf8f5;
  text-align: center;
}
[data-theme="dark"] .cta-banner { background: var(--color-accent-light); color: var(--color-text); }

.cta-banner h2 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  margin-bottom: var(--space-3);
}
.cta-banner p {
  font-size: var(--text-base);
  opacity: 0.85;
  max-width: 55ch;
  margin-inline: auto;
  margin-bottom: var(--space-6);
  line-height: 1.65;
}
.cta-banner .btn-primary {
  background: var(--color-primary);
  color: #faf8f5;
}
[data-theme="dark"] .cta-banner .btn-primary {
  background: var(--color-primary);
  color: #141210;
}

/* -- Contact section -- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-8);
  margin-top: var(--space-8);
}
@media (max-width: 640px) {
  .contact-grid { grid-template-columns: 1fr; }
}
.contact-info h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-4);
}
.contact-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}
.contact-item svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--color-primary);
  margin-top: 2px;
}
.contact-item a {
  color: var(--color-text);
  text-decoration: none;
  font-size: var(--text-sm);
}
.contact-item a:hover { color: var(--color-primary); }
.contact-item p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
}

.legal-box {
  background: var(--color-surface);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
}
.legal-box h3 {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-3);
}
.legal-box p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: var(--space-2);
}

/* -- Footer -- */
.site-footer {
  border-top: 1px solid var(--color-divider);
  padding-block: var(--space-8);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-4);
}
.footer-copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.footer-links {
  display: flex;
  gap: var(--space-6);
}
.footer-links a {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-decoration: none;
}
.footer-links a:hover { color: var(--color-primary); }

/* -- Scroll fade-in -- */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}