:root {
  --brand-dark: #0f172a;
  --brand-light: #f8fafc;
  --brand-primary: #2563eb;
  --brand-secondary: #4f46e5;
  --brand-accent: #38bdf8;
  --brand-danger: #f59e0b;
  --text-dark: #1e293b;
  --text-muted: #64748b;
  --surface: rgba(255,255,255,0.9);
}
*, *::before, *::after { box-sizing: border-box; }
html, body { margin:0; padding:0; font-family: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif; color: var(--text-dark); background: linear-gradient(120deg, #f8fafc 0%, #e0e7ff 100%); min-height:100%; }
a { color: inherit; }
.visually-hidden { position:absolute; width:1px; height:1px; padding:0; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0; }
.site-shell { min-height: 100vh; display:flex; flex-direction:column; }

/* Navigation styles */
.site-nav { background: rgba(15, 23, 42, 0.96); color:#fff; position:sticky; top:0; z-index:40; box-shadow:0 12px 24px rgba(15,23,42,0.18); }
.nav-inner { max-width:1120px; margin:0 auto; padding:0.9rem 1.5rem; display:flex; align-items:center; gap:1rem; justify-content:space-between; }
.nav-brand { display:flex; align-items:center; gap:0.65rem; font-weight:600; letter-spacing:0.02em; text-decoration:none; color:inherit; }
.nav-brand svg { width:1.6rem; height:1.6rem; color:#38bdf8; }
.nav-toggle { display:none; padding:0.45rem; border:1px solid rgba(148,163,184,0.4); border-radius:0.65rem; background:rgba(15,23,42,0.4); color:#fff; cursor:pointer; transition:background 0.2s ease; }
.nav-toggle:hover, .nav-toggle:focus-visible { background:rgba(148,163,184,0.25); }
.nav-toggle span { display:block; width:1.5rem; height:0.14rem; background:currentColor; position:relative; transition:transform 0.2s ease; }
.nav-toggle span::before,
.nav-toggle span::after { content:""; position:absolute; left:0; width:100%; height:100%; background:currentColor; transition:transform 0.2s ease; }
.nav-toggle span::before { top:-0.4rem; }
.nav-toggle span::after { top:0.4rem; }
.nav-links { display:flex; align-items:center; gap:1.25rem; }
.nav-link { color:rgba(255,255,255,0.85); text-decoration:none; font-size:0.98rem; transition:color 0.2s ease; }
.nav-link:hover, .nav-link:focus-visible { color:#fff; }
.nav-link.active { color: var(--brand-accent); font-weight:600; }
.nav-cta { display:flex; align-items:center; gap:0.45rem; padding:0.45rem 0.85rem; border-radius:999px; background:rgba(56,189,248,0.18); color:#e0f2fe; font-weight:600; letter-spacing:0.01em; }
.nav-cta svg { width:1.15rem; height:1.15rem; }
@media (max-width: 960px) {
  .nav-toggle { display:inline-flex; }
  .nav-links { position:absolute; top:100%; left:0; right:0; flex-direction:column; align-items:flex-start; background:rgba(15,23,42,0.97); padding:1.1rem 1.5rem; gap:0.8rem; border-bottom-left-radius:1.2rem; border-bottom-right-radius:1.2rem; max-height:0; overflow:hidden; opacity:0; pointer-events:none; transition:max-height 0.25s ease, opacity 0.25s ease; }
  .nav-links.open { max-height:360px; opacity:1; pointer-events:auto; }
  .nav-link, .nav-cta { width:100%; }
}

/* Utility classes */
.d-none { display:none !important; }
.icon { width:1em; height:1em; display:inline-block; }
.icon-sm { width:0.95rem; height:0.95rem; }
.icon-lg { width:1.45rem; height:1.45rem; }
.icon-sprite { position:absolute; width:0; height:0; overflow:hidden; }

/* Button styles */
.btn { display:inline-flex; align-items:center; justify-content:center; gap:0.6rem; padding:0.75rem 1.4rem; border-radius:12px; border:1.5px solid transparent; font-weight:600; text-decoration:none; cursor:pointer; transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border 0.2s ease; }
.btn svg { width:1.05rem; height:1.05rem; }
.btn-primary { background: linear-gradient(135deg, var(--brand-primary), var(--brand-secondary)); color:#fff; box-shadow:0 16px 32px rgba(37, 99, 235, 0.25); }
.btn-primary:hover, .btn-primary:focus-visible { transform:translateY(-1px); box-shadow:0 22px 44px rgba(37, 99, 235, 0.32); }
.btn-outline { background:transparent; color:var(--brand-primary); border-color:rgba(37, 99, 235, 0.4); box-shadow:0 12px 24px rgba(15, 23, 42, 0.08); }
.btn-outline:hover, .btn-outline:focus-visible { background:rgba(37, 99, 235, 0.1); border-color:rgba(37, 99, 235, 0.6); }
.btn-secondary { background:rgba(15, 23, 42, 0.05); color:var(--text-dark); border-color:rgba(15, 23, 42, 0.12); }
.btn-sm { padding:0.55rem 1rem; font-size:0.92rem; }

/* Badge styles */
.badge { display:inline-flex; align-items:center; gap:0.5rem; border-radius:999px; padding:0.4rem 1rem; font-weight:600; font-size:0.95rem; letter-spacing:0.02em; text-transform:uppercase; }
.badge svg { width:1rem; height:1rem; }
.badge-soft { background: rgba(37, 99, 235, 0.15); color: var(--brand-primary); }
.badge-pill { border-radius:999px; background: rgba(148, 163, 184, 0.2); color: var(--text-dark); font-weight:500; }
.badge-stack { display:flex; flex-wrap:wrap; gap:0.75rem; }
.badge-stack .badge { text-transform:none; font-size:0.92rem; padding:0.4rem 0.9rem; box-shadow:0 12px 24px rgba(37, 99, 235, 0.12); }
.badge-primary { background: linear-gradient(135deg, #2563eb, #3b82f6); color:#fff; }
.badge-success { background: linear-gradient(135deg, #16a34a, #22c55e); color:#fff; }
.badge-info { background: linear-gradient(135deg, #38bdf8, #0ea5e9); color:#0f172a; }

/* Authentication pages - common styles for mobile */
@media (max-width: 680px) {
  .btn { width:100%; justify-content:center; }
  .badge-stack { gap:0.6rem; }
}