/* =========================================================
   Devil's Advocate — shared UI primitives
   Source of truth for colors, typography, and component styles
   used across landing, high-school, debate-ai, learn, devils-advocate.
   Mirrors the main app (app/index.html) aesthetic so every page
   reads as the same product.
   ========================================================= */

/* ── Tokens (default: grey/dark) ─────────────────────────── */
:root,
body{
  --bg:#111;
  --bg-card:rgba(255,255,255,.03);
  --bg-elev:rgba(20,20,24,.55);
  --border:rgba(255,255,255,.08);
  --border-strong:rgba(255,255,255,.18);
  --text:#fff;
  --text-dim:rgba(255,255,255,.55);
  --text-ghost:rgba(255,255,255,.15);
  --accent:#ef4444;
  --accent-hover:#f87171;
  --accent-soft:rgba(239,68,68,.08);
  --accent-border:rgba(239,68,68,.25);
  --accent-glow:rgba(200,30,30,.35);
  --accent-glow2:rgba(80,20,20,.25);
  --radius-sm:6px;
  --radius:10px;
  --radius-lg:14px;
  --radius-pill:999px;
  --shadow-sm:0 2px 10px rgba(0,0,0,.2);
  --shadow:0 6px 18px rgba(0,0,0,.35);
  --shadow-lg:0 20px 60px rgba(0,0,0,.45);
  --ease:cubic-bezier(.2,.65,.3,.9);
}
body.light-theme{
  --bg:#f5f5f7;
  --bg-card:rgba(0,0,0,.03);
  --bg-elev:rgba(255,255,255,.8);
  --border:rgba(0,0,0,.1);
  --border-strong:rgba(0,0,0,.18);
  --text:#111;
  --text-dim:rgba(0,0,0,.55);
  --text-ghost:rgba(0,0,0,.12);
  --accent:#2563eb;
  --accent-hover:#1d4ed8;
  --accent-soft:rgba(37,99,235,.08);
  --accent-border:rgba(37,99,235,.25);
  --accent-glow:rgba(37,99,235,.18);
  --accent-glow2:rgba(37,99,235,.08);
}
body.crimson-theme{
  --bg:#000;
  --bg-card:rgba(255,40,40,.03);
  --bg-elev:rgba(30,10,10,.55);
  --border:rgba(239,68,68,.12);
  --border-strong:rgba(239,68,68,.28);
  --text:#fff;
  --text-dim:rgba(255,255,255,.55);
  --text-ghost:rgba(239,68,68,.15);
  --accent:#ef4444;
  --accent-hover:#f87171;
  --accent-soft:rgba(239,68,68,.08);
  --accent-border:rgba(239,68,68,.3);
  --accent-glow:rgba(239,68,68,.4);
  --accent-glow2:rgba(239,68,68,.2);
}

/* ── Base ─────────────────────────────────────────────────── */
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:'Inter',system-ui,-apple-system,Segoe UI,sans-serif;
  -webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
  background:var(--bg);color:var(--text);
  font-size:16px;line-height:1.55;
  transition:background .4s,color .4s;
}
a{color:inherit}
::selection{background:var(--accent);color:#fff}

/* ── Beta strip (fixed, top of every page) ───────────────── */
.ui-beta-strip{
  position:fixed;top:0;left:0;right:0;z-index:10000;
  padding:6px 36px 6px 14px;text-align:center;
  font-size:.72rem;color:#fff;font-weight:600;letter-spacing:.02em;
  /* Fully opaque — earlier alpha of `dd` let hero content bleed through when it scrolled under */
  background:linear-gradient(90deg,#ef4444,#f59e0b);
  border-bottom:1px solid #00000040;
  font-family:'Inter',system-ui,sans-serif;line-height:1.4;
  box-shadow:0 2px 8px rgba(0,0,0,.35);
}
.ui-beta-strip a{color:#fff;text-decoration:underline;font-weight:800}
.ui-beta-strip-dismiss{
  position:absolute;right:8px;top:50%;transform:translateY(-50%);
  background:transparent;border:none;color:#fff;opacity:.7;
  cursor:pointer;font-size:1rem;line-height:1;padding:4px 6px;
}
.ui-beta-strip-dismiss:hover{opacity:1}
body.has-beta-strip{padding-top:32px}

/* ── Neural constellation canvas (fixed bg) ──────────────── */
.ui-neural-canvas{
  position:fixed;top:0;left:0;width:100vw;height:100vh;
  z-index:1;pointer-events:none;opacity:.45;
  transition:opacity 1s ease;
}
body.crimson-theme .ui-neural-canvas{opacity:.8}
body.light-theme .ui-neural-canvas{opacity:.35}

/* ── Top bar ─────────────────────────────────────────────── */
.ui-topbar{
  position:fixed;top:32px;left:0;right:0;z-index:1000;
  padding:0 32px;height:52px;
  display:flex;align-items:center;justify-content:space-between;
  background:color-mix(in srgb,var(--bg) 88%,transparent);
  border-bottom:1px solid var(--border);
  backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);
  transition:top .2s ease,background .4s,border-color .4s;
}
body:not(.has-beta-strip) .ui-topbar{top:0}
.ui-topbar-left{display:flex;align-items:center;gap:0;flex-shrink:0}
.ui-topbar-logo{
  font-size:1.15rem;font-weight:900;letter-spacing:-.02em;
  color:var(--text);cursor:pointer;white-space:nowrap;line-height:1;
  text-decoration:none;display:inline-block;
}
.ui-topbar-logo span{color:var(--accent)}
.ui-topbar-right{display:flex;align-items:center;gap:14px;flex-shrink:0}
.ui-topbar-link{
  font-size:.72rem;font-weight:500;line-height:18px;
  color:var(--text-dim);letter-spacing:.04em;
  text-decoration:none;background:transparent;border:none;
  padding:0;cursor:pointer;transition:color .2s;
  font-family:inherit;white-space:nowrap;
}
.ui-topbar-link:hover{color:var(--text)}
.ui-topbar-link.accent{color:var(--accent)}
.ui-topbar-link.accent:hover{color:var(--accent-hover)}
.ui-topbar-pill{
  font-size:.7rem;font-weight:500;padding:4px 12px;border-radius:999px;
  border:1px solid var(--border-strong);background:var(--bg-card);
  color:var(--text-dim);cursor:pointer;letter-spacing:.04em;
  text-decoration:none;font-family:inherit;transition:.2s;
}
.ui-topbar-pill:hover{color:var(--text);border-color:var(--text)}
@media(max-width:640px){
  .ui-topbar{padding:0 12px;height:48px;top:28px}
  .ui-topbar-logo{font-size:.95rem}
  .ui-topbar-right{gap:10px}
  .ui-topbar-link{font-size:.65rem}
}

/* ── Nav tabs (pill row, uppercase) ──────────────────────── */
.ui-nav{
  display:flex;gap:16px;margin:0 auto 48px;padding:4px 32px;
  flex-wrap:nowrap;justify-content:center;align-items:center;
  max-width:100%;width:100%;
  position:sticky;top:calc(32px + 52px);z-index:999;
  overflow-x:auto;overflow-y:visible;
  -webkit-overflow-scrolling:touch;scrollbar-width:none;
}
body:not(.has-beta-strip) .ui-nav{top:52px}
.ui-nav::-webkit-scrollbar{display:none}
.ui-nav-btn{
  background:var(--bg-elev);border:1px solid var(--border);
  color:var(--text-dim);
  padding:13px 26px;border-radius:var(--radius-pill);
  font-size:.82rem;font-weight:700;letter-spacing:.05em;text-transform:uppercase;
  cursor:pointer;transition:all .2s var(--ease);
  font-family:inherit;white-space:nowrap;text-decoration:none;flex-shrink:0;
  box-shadow:var(--shadow-sm);
}
.ui-nav-btn:hover{
  color:var(--text);background:rgba(40,40,48,.75);
  border-color:var(--border-strong);transform:translateY(-1px);
  box-shadow:var(--shadow);
}
.ui-nav-btn.active{
  color:#fff;background:var(--accent);border-color:var(--accent);
  box-shadow:0 6px 24px var(--accent-glow);
}
@media(max-width:640px){
  .ui-nav{padding:12px 14px 10px;gap:8px;justify-content:flex-start}
  .ui-nav-btn{padding:9px 18px;font-size:.72rem}
}

/* ── Page shell / sections ───────────────────────────────── */
.ui-shell{
  position:relative;z-index:2;min-height:100vh;
  display:flex;flex-direction:column;align-items:center;
  width:100%;max-width:100vw;overflow-x:hidden;
  padding-top:96px; /* clear beta strip + topbar */
}
body:not(.has-beta-strip) .ui-shell{padding-top:64px}
.ui-section{padding:80px 24px;width:100%}
.ui-section-sm{padding:48px 24px;width:100%}
.ui-container{max-width:1100px;margin:0 auto;width:100%}
.ui-container-sm{max-width:760px;margin:0 auto;width:100%}
.ui-divider{height:1px;max-width:1100px;margin:0 auto;background:var(--border)}

/* ── Typography ──────────────────────────────────────────── */
.ui-eyebrow{
  display:inline-block;font-size:.72rem;font-weight:700;
  letter-spacing:.14em;text-transform:uppercase;color:var(--accent);
  margin-bottom:20px;
}
.ui-h1{
  font-size:clamp(2.2rem,5vw,3.8rem);font-weight:900;
  text-transform:uppercase;letter-spacing:-.03em;line-height:.95;
  color:var(--text);margin:0 0 16px;
}
.ui-h1 .accent{color:var(--accent)}
.ui-h2{
  font-size:clamp(1.6rem,3.4vw,2.4rem);font-weight:800;
  letter-spacing:-.02em;line-height:1.1;color:var(--text);margin:0 0 14px;
}
.ui-h3{
  font-size:1.1rem;font-weight:700;letter-spacing:-.01em;
  line-height:1.25;color:var(--text);margin:0 0 8px;
}
.ui-lede{
  font-size:clamp(.95rem,1.4vw,1.1rem);color:var(--text-dim);
  line-height:1.65;max-width:620px;margin:0 auto 28px;font-weight:400;
}
.ui-p{font-size:.95rem;color:var(--text-dim);line-height:1.65;margin:0 0 14px}
.ui-muted{color:var(--text-dim)}

/* ── Buttons ─────────────────────────────────────────────── */
.ui-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:14px 32px;border-radius:var(--radius-pill);
  font-size:.82rem;font-weight:700;letter-spacing:.06em;text-transform:uppercase;
  font-family:inherit;cursor:pointer;text-decoration:none;
  border:1px solid transparent;transition:transform .2s var(--ease),background .2s,border-color .2s,box-shadow .2s;
  white-space:nowrap;
}
.ui-btn:hover{transform:translateY(-1px)}
.ui-btn-primary{
  background:var(--accent);color:#fff;border-color:var(--accent);
  box-shadow:0 6px 24px var(--accent-glow);
}
.ui-btn-primary:hover{background:var(--accent-hover);border-color:var(--accent-hover)}
.ui-btn-secondary{
  background:var(--bg-elev);color:var(--text);border-color:var(--border-strong);
}
.ui-btn-secondary:hover{background:rgba(40,40,48,.75);border-color:var(--text)}
.ui-btn-ghost{
  background:transparent;color:var(--text-dim);border-color:var(--border);
}
.ui-btn-ghost:hover{color:var(--text);border-color:var(--border-strong)}
.ui-btn-sm{padding:10px 20px;font-size:.72rem}

/* ── Badges / chips ──────────────────────────────────────── */
.ui-badge{
  display:inline-flex;align-items:center;gap:6px;
  padding:5px 12px;border-radius:var(--radius-pill);
  font-size:.7rem;font-weight:600;letter-spacing:.06em;text-transform:uppercase;
  border:1px solid var(--border);color:var(--text-dim);background:var(--bg-card);
}
.ui-badge.accent{border-color:var(--accent-border);color:var(--accent-hover);background:var(--accent-soft)}
.ui-chip{
  display:inline-flex;align-items:center;gap:6px;
  padding:8px 16px;border-radius:var(--radius-pill);
  font-size:.78rem;font-weight:500;color:var(--text-dim);
  background:var(--bg-card);border:1px solid var(--border);
  transition:border-color .2s,color .2s;
}
.ui-chip:hover{color:var(--text);border-color:var(--border-strong)}

/* ── Cards ───────────────────────────────────────────────── */
.ui-card{
  background:var(--bg-card);border:1px solid var(--border);
  border-radius:var(--radius-lg);padding:22px;
  transition:border-color .2s,transform .2s;
}
.ui-card:hover{border-color:var(--border-strong)}
.ui-card-label{
  display:block;font-size:.7rem;font-weight:700;color:var(--accent);
  text-transform:uppercase;letter-spacing:.08em;margin-bottom:6px;
}
.ui-card-body{font-size:.88rem;color:var(--text-dim);line-height:1.55}
.ui-grid{display:grid;gap:14px}
.ui-grid-2{grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}
.ui-grid-3{grid-template-columns:repeat(auto-fit,minmax(220px,1fr))}

/* ── Footer ──────────────────────────────────────────────── */
.ui-footer{
  padding:48px 24px 32px;border-top:1px solid var(--border);
  text-align:center;font-size:.78rem;color:var(--text-dim);line-height:1.6;
}
.ui-footer a{color:var(--text-dim);text-decoration:none;transition:color .2s}
.ui-footer a:hover{color:var(--text)}
.ui-footer-row{
  display:flex;gap:20px;justify-content:center;flex-wrap:wrap;
  margin-bottom:12px;
}

/* ── Reduced motion ──────────────────────────────────────── */
@media (prefers-reduced-motion:reduce){
  *{animation-duration:.01ms!important;transition-duration:.01ms!important}
  .ui-nav-btn:hover,.ui-btn:hover{transform:none}
}