/**
 * shell.css — VF Business Chess League
 *
 * Shared styles: design tokens, nav, footer, page-hero, and common
 * utilities used across all inner pages (partnership, sponsors, register).
 *
 * index.html uses its own inline <style> for page-specific layout.
 * All inner pages link this file instead of duplicating these rules.
 */

/* ── RESET & TOKENS ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --navy:    #0A0E1A;
  --navy-2:  #111829;
  --navy-3:  #1E2640;
  --navy-4:  #2A3560;
  --amber:   #F59E0B;
  --amber-2: #D97706;
  --amber-3: #FCD34D;
  --ivory:   #F5F0E8;
  --ivory-2: #D4CBBA;
  --slate:   #8893AE;
  --red:     #EF4444;
  --font-display: 'Playfair Display', Georgia, serif;
  --font-body:    'Inter', system-ui, sans-serif;
}

html { scroll-behavior: smooth; }

body {
  background: var(--navy);
  color: var(--ivory);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
}

/* ── NAV ── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(1.5rem, 5vw, 4rem);
  height: 68px;
  background: rgba(10,14,26,0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(245,158,11,0.12);
  transition: background 0.3s;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
}

.nav-logo-text {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--ivory);
  letter-spacing: 0.01em;
}

.nav-logo-text span { color: var(--amber); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--slate);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: color 0.2s;
}

.nav-links a:hover { color: var(--ivory); }

.nav-cta {
  background: var(--amber);
  color: var(--navy) !important;
  padding: 0.5rem 1.25rem;
  border-radius: 6px;
  font-weight: 600 !important;
  transition: background 0.2s, transform 0.15s !important;
}

.nav-cta:hover {
  background: var(--amber-3) !important;
  transform: translateY(-1px);
}

/* Language switcher */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 2px;
  background: var(--navy-3);
  border: 1px solid var(--navy-4);
  border-radius: 6px;
  padding: 2px;
}

.lang-btn {
  padding: 0.3rem 0.625rem;
  border-radius: 4px;
  border: none;
  background: transparent;
  color: var(--slate);
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.lang-btn:hover { color: var(--ivory); }

.lang-btn.active {
  background: var(--amber);
  color: var(--navy);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--ivory);
  border-radius: 2px;
  transition: 0.3s;
}

/* ── PAGE HERO (inner pages) ── */
.page-hero {
  padding: 140px clamp(1.5rem, 5vw, 4rem) 80px;
  background: var(--navy-2);
  border-bottom: 1px solid var(--navy-4);
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 50% 80% at 80% 50%, rgba(245,158,11,0.06) 0%, transparent 70%);
  pointer-events: none;
}

.page-hero-inner { max-width: 680px; }

/* ── SHARED TYPOGRAPHY ── */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 1rem;
}

.eyebrow::before {
  content: '';
  display: block;
  width: 20px;
  height: 1px;
  background: var(--amber);
}

.page-headline {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 900;
  line-height: 1.1;
  color: var(--ivory);
  margin-bottom: 1.25rem;
}

.page-sub {
  font-size: 1.0625rem;
  color: var(--slate);
  line-height: 1.75;
  max-width: 560px;
}

/* ── SHARED LAYOUT ── */
.page-body {
  padding: clamp(3rem, 6vw, 5rem) clamp(1.5rem, 5vw, 4rem);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--slate);
  font-size: 0.875rem;
  text-decoration: none;
  margin-bottom: 2rem;
  transition: color 0.2s;
}

.back-link:hover { color: var(--amber); }

/* ── SHARED CARDS ── */
.info-cards {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.info-card {
  background: var(--navy-3);
  border: 1px solid var(--navy-4);
  border-radius: 12px;
  padding: 1.75rem;
  transition: border-color 0.2s, transform 0.2s;
}

.info-card:hover {
  border-color: rgba(245,158,11,0.25);
  transform: translateX(4px);
}

.info-card h3 {
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--ivory);
  margin-bottom: 0.625rem;
}

.info-card p {
  font-size: 0.9375rem;
  color: var(--slate);
  line-height: 1.7;
}

/* ── SHARED FORM ELEMENTS ── */
.form-card {
  background: var(--navy-3);
  border: 1px solid var(--navy-4);
  border-radius: 16px;
  padding: 2.25rem;
}

.form-title {
  font-family: var(--font-display);
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--ivory);
  margin-bottom: 1.75rem;
}

.form-group { margin-bottom: 1.25rem; }

.form-group label {
  display: block;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--ivory-2);
  letter-spacing: 0.04em;
  margin-bottom: 0.4rem;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  background: var(--navy-2);
  border: 1px solid var(--navy-4);
  border-radius: 8px;
  padding: 0.75rem 1rem;
  color: var(--ivory);
  font-family: var(--font-body);
  font-size: 0.9375rem;
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder { color: var(--slate); }

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--amber);
  box-shadow: 0 0 0 3px rgba(245,158,11,0.1);
}

.form-group input.required-missing {
  border-color: var(--red);
  box-shadow: 0 0 0 3px rgba(239,68,68,0.1);
}

.form-group textarea { resize: vertical; }

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--amber);
  color: var(--navy);
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 700;
  padding: 0.875rem 1.75rem;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  width: 100%;
  justify-content: center;
  margin-top: 0.5rem;
}

.btn-primary:hover {
  background: var(--amber-3);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(245,158,11,0.25);
}

.form-note {
  font-size: 0.8125rem;
  color: var(--slate);
  text-align: center;
  margin-top: 0.875rem;
}

/* ── FOOTER ── */
footer {
  background: var(--navy-2);
  border-top: 1px solid var(--navy-4);
  padding: 3.5rem clamp(1.5rem, 5vw, 4rem) 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  font-size: 0.9rem;
  color: var(--slate);
  line-height: 1.7;
  margin-top: 0.875rem;
  max-width: 240px;
}

.footer-col h5 {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ivory);
  margin-bottom: 1rem;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
}

.footer-col a {
  font-size: 0.9rem;
  color: var(--slate);
  text-decoration: none;
  transition: color 0.2s;
}

.footer-col a:hover { color: var(--amber); }

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid var(--navy-4);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer-bottom p {
  font-size: 0.8125rem;
  color: var(--slate);
}

.footer-social { display: flex; gap: 0.75rem; }

.footer-social a {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: var(--navy-3);
  border: 1px solid var(--navy-4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  color: var(--slate);
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
}

.footer-social a:hover {
  border-color: var(--amber);
  color: var(--amber);
  background: rgba(245,158,11,0.08);
}

/* ── RESPONSIVE ── */
@media (max-width: 900px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
}

@media (max-width: 600px) {
  .nav-links { display: none; }
  .hamburger { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    background: var(--navy-2);
    border-bottom: 1px solid var(--navy-4);
    padding: 1.5rem clamp(1.5rem, 5vw, 4rem);
    gap: 1.25rem;
  }

  .footer-grid { grid-template-columns: 1fr; }
  .form-row    { grid-template-columns: 1fr; }
}