/* OpenAEC Foundation — Shared Stylesheet v1.0 */
/* Based on DESIGN-SYSTEM.md v0.3 */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;700&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  /* Colors */
  --amber: #D97706;
  --deep-forge: #36363E;
  --signal-orange: #EA580C;
  --warm-gold: #F59E0B;
  --scaffold-gray: #A1A1AA;
  --blueprint-white: #FAFAF9;
  --concrete: #F5F5F4;
  --night-build: #2A2A32;
  --success: #16A34A;
  --error: #DC2626;
  --info: #2563EB;

  /* Typography */
  --font-heading: "Space Grotesk", system-ui, sans-serif;
  --font-body: "Inter", system-ui, sans-serif;
  --font-code: "JetBrains Mono", monospace;

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

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);

  /* Gradient */
  --gradient-accent: linear-gradient(90deg, #D97706 0%, #F59E0B 40%, #EA580C 100%);
}

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

body {
  font-family: var(--font-body);
  color: var(--deep-forge);
  background-color: var(--blueprint-white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3 {
  font-family: var(--font-heading);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 500;
  letter-spacing: -0.01em;
  line-height: 1.3;
}
h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p { max-width: 70ch; }

a { color: var(--amber); text-decoration: none; }
a:hover { color: var(--signal-orange); }

code, pre {
  font-family: var(--font-code);
  font-size: 0.875rem;
}
code {
  background: var(--concrete);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
}
pre {
  background: var(--night-build);
  color: var(--blueprint-white);
  padding: var(--sp-6);
  border-radius: var(--radius-md);
  overflow-x: auto;
  line-height: 1.5;
}
pre code {
  background: none;
  padding: 0;
}

/* Section label */
.section-label {
  font-family: var(--font-code);
  font-weight: 500;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--amber);
}

/* Navigation */
.navbar {
  background: var(--deep-forge);
  border-bottom: 3px solid transparent;
  border-image: var(--gradient-accent) 1;
  padding: var(--sp-4) var(--sp-6);
  position: sticky;
  top: 0;
  z-index: 1000;
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.nav-brand {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.25rem;
  color: white;
  text-decoration: none;
}
.nav-brand .accent { color: var(--amber); }
.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--sp-6);
}
.nav-links {
  display: flex;
  gap: var(--sp-6);
  list-style: none;
  align-items: center;
}
.nav-links a {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.875rem;
  color: var(--scaffold-gray);
  text-decoration: none;
  transition: color 0.15s ease;
  white-space: nowrap;
}
.nav-links a:hover { color: white; }
.nav-links a.active { color: var(--amber); }
.nav-feedback-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--amber);
  color: var(--night-build);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
  text-decoration: none;
  flex-shrink: 0;
  transition: background 0.2s;
}
.nav-feedback-btn:hover {
  background: var(--amber-light);
}
.lang-switcher {
  display: flex;
  gap: var(--sp-1);
  flex-shrink: 0;
}
.lang-btn {
  background: none;
  border: 1px solid var(--scaffold-gray);
  color: var(--scaffold-gray);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}
.lang-btn.active {
  background: var(--amber);
  border-color: var(--amber);
  color: white;
}
.lang-btn:hover { color: white; border-color: white; }

/* Hero */
.hero {
  background: var(--night-build);
  padding: var(--sp-24) var(--sp-6);
  text-align: center;
}
.hero .section-label {
  color: var(--warm-gold);
  margin-bottom: var(--sp-4);
  display: block;
}
.hero h1 {
  color: white;
  font-size: 3rem;
  margin-bottom: var(--sp-4);
}
.hero h1 .accent { color: var(--amber); }
.hero .tagline {
  font-size: 1.25rem;
  color: var(--scaffold-gray);
  margin-bottom: var(--sp-8);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  border: none;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  text-decoration: none;
}
.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn-primary {
  background: var(--amber);
  color: white;
}
.btn-primary:hover { background: var(--signal-orange); color: white; }
.btn-secondary {
  background: transparent;
  color: var(--deep-forge);
  border: 2px solid var(--deep-forge);
}
.btn-secondary:hover {
  background: var(--deep-forge);
  color: white;
}
.btn-ghost {
  background: transparent;
  color: var(--amber);
  border: 2px solid var(--amber);
}
.btn-ghost:hover {
  background: var(--amber);
  color: white;
}
.btn-dark {
  background: var(--deep-forge);
  color: var(--blueprint-white);
}
.btn-dark:hover { background: #27272A; color: var(--blueprint-white); }
.btn-sm { font-size: 0.75rem; padding: 8px 16px; }
.btn-lg { font-size: 1rem; padding: 16px 32px; }
.btn-group { display: flex; gap: var(--sp-4); flex-wrap: wrap; justify-content: center; }

/* Cards */
.card {
  background: white;
  border: 1px solid #E7E5E4;
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.15s ease, border-color 0.15s ease;
}
.card:hover {
  box-shadow: var(--shadow-md);
  border-color: #D6D3D1;
}
.card.featured { border: 2px solid var(--amber); }
.card-dark {
  background: var(--deep-forge);
  border: 1px solid #27272A;
  color: var(--blueprint-white);
}

/* Badges */
.badge {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.2em 0.6em;
  border-radius: var(--radius-full);
  display: inline-block;
}
.badge-amber { background: #FEF3C7; color: #92400E; }
.badge-green { background: #DCFCE7; color: #166534; }
.badge-blue { background: #DBEAFE; color: #1E40AF; }
.badge-gray { background: #F4F4F5; color: #3F3F46; }

/* Tags */
.tag {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  border: 1px solid #E7E5E4;
  color: #57534E;
  background: white;
  display: inline-block;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--sp-6);
}

/* Sections */
.section {
  padding: var(--sp-16) var(--sp-6);
}
.section-alt {
  background: var(--concrete);
}
.section-dark {
  background: var(--deep-forge);
  color: var(--blueprint-white);
}

/* Grid */
.grid {
  display: grid;
  gap: var(--sp-6);
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Release card */
.release-card {
  background: white;
  border: 1px solid #E7E5E4;
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.15s ease, border-color 0.15s ease;
}
.release-card:hover {
  box-shadow: var(--shadow-md);
  border-color: #D6D3D1;
}
.release-card .version {
  font-family: var(--font-code);
  font-weight: 500;
  color: var(--amber);
  font-size: 0.875rem;
}
.release-card .date {
  font-size: 0.75rem;
  color: var(--scaffold-gray);
}
.release-card h4 { margin: var(--sp-2) 0; }

/* Download section */
.download-section {
  background: var(--night-build);
  border-radius: var(--radius-lg);
  padding: var(--sp-8);
  margin: var(--sp-8) 0;
}
.download-section h3 { color: white; margin-bottom: var(--sp-4); }
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--sp-4);
}
.download-item {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
  text-align: center;
}
.download-item .os {
  font-weight: 600;
  color: var(--blueprint-white);
  margin-bottom: var(--sp-2);
}
.download-item .size {
  font-size: 0.75rem;
  color: var(--scaffold-gray);
  margin-bottom: var(--sp-3);
}

/* Features list */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--sp-6);
}
.feature {
  padding: var(--sp-6);
}
.feature-icon {
  font-size: 2rem;
  margin-bottom: var(--sp-3);
}
.feature h4 { margin-bottom: var(--sp-2); }
.feature p {
  color: #57534E;
  font-size: 0.875rem;
}

/* Footer */
.footer {
  background: var(--deep-forge);
  border-top: 3px solid transparent;
  border-image: var(--gradient-accent) 1;
  padding: var(--sp-8) var(--sp-6);
  color: var(--scaffold-gray);
  font-size: 0.875rem;
}
.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--sp-4);
}
.footer a { color: var(--scaffold-gray); }
.footer a:hover { color: white; }
.footer .nav-brand { font-size: 1rem; }

/* Hamburger menu */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  z-index: 1001;
}
.hamburger span {
  display: block;
  width: 28px;
  height: 3px;
  background: white;
  margin: 6px 0;
  border-radius: 2px;
  transition: all 0.3s ease;
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.6rem; word-break: break-word; overflow-wrap: anywhere; }
  .hero .tagline { font-size: 0.95rem; }
  .hero { padding: var(--sp-8) var(--sp-4) !important; }
  .page-header h1 { font-size: 1.6rem; word-break: break-word; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .hamburger { display: block; }
  .nav-menu { display: none !important; }
  .nav-menu.active {
    display: flex !important;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--deep-forge);
    padding: var(--sp-4) var(--sp-6);
    border-bottom: 3px solid transparent;
    border-image: var(--gradient-accent) 1;
    z-index: 1000;
    gap: var(--sp-2);
  }
  .nav-menu.active .nav-links {
    display: flex !important;
    flex-direction: column;
    gap: var(--sp-3);
  }
  .nav-menu.active .nav-links a {
    font-size: 1rem;
    padding: var(--sp-2) 0;
  }
  .nav-menu.active .lang-switcher {
    display: flex !important;
    margin-left: 0;
    margin-top: var(--sp-3);
    justify-content: flex-start;
  }
  .nav-menu.active .nav-feedback-btn {
    display: inline-flex;
    align-self: flex-start;
    margin-top: var(--sp-2);
  }
  .navbar .nav-container { position: relative; }
  .footer-container { flex-direction: column; text-align: center; }
  .section { padding: var(--sp-8) var(--sp-4); }
  .download-grid { grid-template-columns: 1fr; }
  .table-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    max-width: 100%;
  }
  table {
    min-width: 600px;
  }
}