/* NSTA Atom demo — CustomGPT.ai sales prop (visual parity with nsta.org) */
:root {
  --navy: #283359;
  --nav: #3A4A6B;
  --cta: #0B6FA4;
  --cta-dark: #095a86;
  --cyan: #1FB5D0;
  --purple: #5B3FD9;
  --teal-banner: #0d5c6b;
  --text: #283359;
  --muted: #5a6570;
  --bg: #f0f3f9;
  --card: #fff;
  --border: #dae2ef;
  --brand: #0B6FA4;
  --brand-dark: #095a86;
  --accent: #5B3FD9;
  --font: "Inter", "Segoe UI", system-ui, sans-serif;
  --radius: 8px;
  --shadow: 0 8px 24px rgba(40, 51, 89, 0.08);
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font-family: var(--font); color: var(--text); background: #fff; line-height: 1.55; }
a { color: var(--cta); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { width: min(1140px, calc(100% - 2.5rem)); margin: 0 auto; }

.demo-banner {
  background: linear-gradient(90deg, #7a00df, #0B6FA4);
  color: #fff; text-align: center; font-size: 0.78rem; padding: 0.4rem 1rem; font-weight: 600;
  position: sticky; top: 0; z-index: 100;
}

.sponsor-bar {
  background: var(--teal-banner);
  background-image: radial-gradient(circle at 20% 50%, rgba(255,255,255,0.06) 0, transparent 40%),
    radial-gradient(circle at 80% 30%, rgba(255,255,255,0.05) 0, transparent 35%);
  color: #fff; padding: 0.85rem 0; font-size: 0.85rem;
}
.sponsor-bar .container { display: flex; align-items: center; gap: 1rem; }
.sponsor-bar .sponsor-logo {
  font-weight: 800; letter-spacing: 0.02em; display: flex; align-items: center; gap: 0.5rem;
}
.sponsor-bar .sponsor-logo span {
  width: 28px; height: 28px; border: 2px solid rgba(255,255,255,0.7); border-radius: 4px;
  display: inline-flex; align-items: center; justify-content: center; font-size: 0.65rem;
}
.sponsor-bar .muted { opacity: 0.75; font-size: 0.78rem; }

.site-header { background: #fff; padding: 1rem 0 0.9rem; }
.site-header .container {
  display: flex; align-items: center; gap: 1rem; flex-wrap: wrap;
}
.logo-mark {
  display: flex; align-items: center; gap: 0.65rem; text-decoration: none !important; color: var(--navy); white-space: nowrap;
}
.atom-mark {
  width: 42px; height: 42px; position: relative; flex-shrink: 0;
}
.atom-mark .orbit {
  position: absolute; inset: 2px; border: 2.5px solid var(--cyan); border-radius: 50%;
  transform: rotate(-25deg);
}
.atom-mark .orbit2 { transform: rotate(35deg); border-color: #4ec8de; opacity: 0.85; }
.atom-mark .core {
  position: absolute; width: 12px; height: 12px; background: #f08a2a; border-radius: 50%;
  left: 50%; top: 50%; transform: translate(-50%,-50%);
  box-shadow: -8px -6px 0 -3px #4ec8de, 8px 4px 0 -3px #4ec8de;
}
.logo-text .word { font-size: 1.75rem; font-weight: 800; letter-spacing: -0.03em; line-height: 1; color: var(--navy); }
.logo-text .sub { font-size: 0.62rem; color: var(--navy); font-weight: 600; margin-top: 0.12rem; max-width: 11rem; line-height: 1.25; }

.demo-hsearch { flex: 1 1 280px; max-width: 420px; position: relative; min-width: 180px; }
.demo-hsearch form { position: relative; margin: 0; display: flex; }
.demo-hsearch input {
  flex: 1; padding: 0.7rem 0.9rem; border: 1px solid #c5d0e0; border-right: none;
  border-radius: 4px 0 0 4px; font-size: 0.92rem; font-family: var(--font); color: var(--navy); background: #fff;
}
.demo-hsearch input:focus { outline: 2px solid rgba(11,111,164,0.3); position: relative; z-index: 1; }
.demo-hsearch .ai-tag {
  position: absolute; right: 52px; top: 50%; transform: translateY(-50%);
  font-size: 0.62rem; font-weight: 800; color: var(--cta); pointer-events: none;
}
.demo-hsearch .go {
  width: 48px; border: none; border-radius: 0 4px 4px 0; background: var(--cta); color: #fff;
  cursor: pointer; font-size: 1.1rem;
}
.demo-hsearch .go:hover { background: var(--cta-dark); }
.demo-searchdrop {
  display: none; position: absolute; top: calc(100% + 10px); left: 0; right: 0;
  min-width: min(520px, 92vw); background: #fff; border: 1px solid var(--border);
  border-radius: 12px; box-shadow: 0 18px 40px rgba(0,0,0,0.18); z-index: 60; overflow: hidden;
}
.demo-searchdrop .sd-head {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--border); background: #f0f3f9;
}
.demo-searchdrop .sd-head .lab { color: var(--cta); letter-spacing: 0.05em; text-transform: uppercase; font-size: 0.72rem; font-weight: 800; }
.demo-searchdrop .sd-close { border: none; background: #e0e6f0; width: 28px; height: 28px; border-radius: 50%; cursor: pointer; font-size: 1.1rem; }
#customgpt_search { width: 100%; min-height: 160px; padding: 4px; }

.header-actions { display: flex; align-items: center; gap: 0.85rem; margin-left: auto; flex-wrap: wrap; }
.ask-atom {
  display: inline-flex; align-items: center; gap: 0.4rem; color: var(--navy); font-weight: 700;
  text-decoration: none !important; font-size: 0.92rem;
}
.ask-atom:hover { color: var(--cta); }
.ask-atom .mini-atom {
  width: 22px; height: 22px; border-radius: 50%; border: 2px solid var(--cyan);
  position: relative; display: inline-block;
}
.ask-atom .mini-atom::after {
  content: ""; position: absolute; width: 6px; height: 6px; background: #f08a2a; border-radius: 50%;
  left: 50%; top: 50%; transform: translate(-50%,-50%);
}
.btn-join {
  background: var(--cta); color: #fff !important; padding: 0.55rem 1rem; border-radius: 4px;
  font-weight: 700; text-decoration: none !important; font-size: 0.9rem;
  display: inline-flex; align-items: center; gap: 0.35rem;
}
.btn-join:hover { background: var(--cta-dark); }
.sign-in { color: #6a7385; font-weight: 600; text-decoration: none; font-size: 0.9rem; }
.sign-in:hover { color: var(--cta); }

.main-nav {
  background: var(--nav); position: sticky; top: 28px; z-index: 40;
}
.main-nav .container { display: flex; align-items: center; gap: 0.5rem; flex-wrap: wrap; }
.nav { display: flex; align-items: center; gap: 0.2rem 1.35rem; flex-wrap: wrap; padding: 0.75rem 0; }
.nav a { color: #fff; font-weight: 600; font-size: 0.88rem; text-decoration: none; }
.nav a:hover, .nav a.active { color: var(--cyan); text-decoration: underline; }
.nav .btn { background: var(--cta); color: #fff !important; padding: 0.4rem 0.85rem; border-radius: 4px; }
.nav-toggle {
  display: none; background: rgba(255,255,255,0.12); border: 1px solid rgba(255,255,255,0.25);
  color: #fff; border-radius: 4px; padding: 0.4rem 0.7rem; font-weight: 700; margin: 0.5rem 0;
}

.hero {
  background: linear-gradient(120deg, #1a2744 0%, #2a3d66 50%, #0B6FA4 100%);
  color: #fff; padding: 3.5rem 0 3rem; position: relative; overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(circle at 85% 40%, rgba(31,181,208,0.25), transparent 45%);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 1; display: grid; grid-template-columns: 1.3fr 1fr; gap: 2rem; align-items: center; }
.hero-kicker {
  display: inline-block; background: rgba(255,255,255,0.12); border: 1px solid rgba(255,255,255,0.25);
  border-radius: 4px; padding: 0.25rem 0.7rem; font-size: 0.75rem; font-weight: 700;
  letter-spacing: 0.04em; text-transform: uppercase; margin-bottom: 0.85rem;
}
.hero h1 { margin: 0 0 0.85rem; font-size: clamp(1.75rem, 3.2vw, 2.4rem); line-height: 1.2; font-weight: 800; }
.hero p { margin: 0 0 1.35rem; color: #d0dcec; max-width: 34rem; font-size: 1.05rem; }
.hero-actions { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.btn-primary, .btn-secondary, .btn-try {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 0.75rem 1.25rem; border-radius: 4px; font-weight: 700; text-decoration: none !important; font-size: 0.95rem;
}
.btn-primary { background: #fff; color: var(--navy) !important; }
.btn-primary:hover { background: #e8f4fb; }
.btn-secondary { background: transparent; color: #fff !important; border: 1.5px solid rgba(255,255,255,0.55); }
.btn-try { background: var(--purple) !important; color: #fff !important; box-shadow: 0 6px 18px rgba(0,0,0,0.2); }
.btn-try:hover { filter: brightness(1.08); }
.hero-card {
  background: rgba(255,255,255,0.1); border: 1px solid rgba(255,255,255,0.2); border-radius: 10px;
  padding: 1.5rem; backdrop-filter: blur(6px); text-align: center;
}
.hero-card .agent-pill {
  display: inline-block; background: rgba(255,255,255,0.18); border-radius: 999px;
  padding: 0.35rem 0.9rem; font-weight: 700; margin-bottom: 0.75rem;
}
.hero-card p { color: #d0dcec; margin: 0 0 1rem; font-size: 0.92rem; }

.tabs-section { background: #fff; padding: 0 0 2.5rem; }
.tabs {
  display: flex; gap: 0; margin-top: -1.25rem; position: relative; z-index: 2; margin-bottom: 1.5rem;
}
.tab {
  flex: 1; text-align: center; padding: 1rem 1.25rem; background: #e8edf5; color: #6a7385;
  font-weight: 700; font-size: 1.05rem; border-radius: 8px 8px 0 0; border: 1px solid var(--border); border-bottom: none;
}
.tab.active { background: #fff; color: var(--purple); box-shadow: 0 -4px 12px rgba(91,63,217,0.08); }
.tabs-body h2 { margin: 0 0 0.5rem; font-size: 1.65rem; color: var(--navy); }
.tabs-body p { margin: 0; color: var(--muted); font-size: 1.05rem; }
.tabs-body a { color: var(--cta); font-weight: 600; text-decoration: underline; }

.section { padding: 3rem 0; }
.section.alt { background: var(--bg); }
.section-head { margin-bottom: 1.5rem; }
.section-head h2 { margin: 0; font-size: 1.55rem; color: var(--navy); }
.section-head p { margin: 0.4rem 0 0; color: var(--muted); max-width: 38rem; }
.eyebrow { color: var(--purple); font-size: 0.75rem; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase; margin: 0 0 0.35rem; }

.grid { display: grid; gap: 1.25rem; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow); display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-2px); box-shadow: 0 12px 28px rgba(40,51,89,0.12); transition: 0.15s; }
.card-accent { height: 5px; background: linear-gradient(90deg, var(--cta), var(--purple)); }
.card-body { padding: 1.15rem; display: flex; flex-direction: column; gap: 0.4rem; flex: 1; }
.card-body .tag {
  align-self: flex-start; background: rgba(91,63,217,0.1); color: var(--purple);
  font-size: 0.7rem; font-weight: 700; letter-spacing: 0.04em; text-transform: uppercase;
  padding: 0.2rem 0.5rem; border-radius: 4px;
}
.card-body h3 { margin: 0; font-size: 1.05rem; color: var(--navy); }
.card-body p { margin: 0; color: var(--muted); font-size: 0.92rem; flex: 1; }

.cta-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.85rem; }
.cta-pill {
  display: block; text-align: center; font-weight: 700; background: #fff; border: 1.5px solid var(--border);
  border-radius: 8px; padding: 1rem 0.75rem; color: var(--navy); text-decoration: none !important; box-shadow: var(--shadow);
}
.cta-pill:hover { border-color: var(--cta); color: var(--cta); }

.cta-band {
  background: linear-gradient(120deg, var(--nav), var(--cta));
  color: #fff; border-radius: 12px; padding: 2rem 2.25rem;
  display: flex; justify-content: space-between; align-items: center; gap: 1.5rem; flex-wrap: wrap;
}
.cta-band h2 { margin: 0 0 0.4rem; font-size: 1.45rem; }
.cta-band p { margin: 0; color: #d0dcec; max-width: 34rem; }

.site-footer { background: var(--navy); color: #b7c3d4; padding: 2.5rem 0 1.5rem; margin-top: 1rem; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 1.5rem; margin-bottom: 1.75rem; }
.site-footer h4 { color: #fff; margin: 0 0 0.7rem; font-size: 0.92rem; }
.site-footer a { color: #c9d6e8; display: block; margin-bottom: 0.35rem; font-size: 0.9rem; text-decoration: none; }
.site-footer a:hover { color: #fff; }
.footer-note { border-top: 1px solid rgba(255,255,255,0.12); padding-top: 1rem; font-size: 0.8rem; color: #8fa0b5; }
.footer-note strong { color: #d5deea; }

.assistant-page { margin: 0; min-height: 100vh; display: flex; flex-direction: column; background: #f5f7fa; }
.assistant-page .assistant-frame { flex: 1; min-height: 0; display: flex; flex-direction: column; }
.assistant-page #customgpt_chat { flex: 1; min-height: calc(100vh - 96px); width: 100%; }
.assistant-bar { background: #fff; border-bottom: 1px solid var(--border); padding: 0.65rem 0; }
.assistant-bar .container { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.assistant-bar a.back { font-weight: 700; color: var(--cta); text-decoration: none; }
.assistant-bar strong { color: var(--navy); }

@media (max-width: 960px) {
  .hero .container, .grid-3, .footer-grid, .cta-strip { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 720px) {
  .nav-toggle { display: inline-block; }
  .nav { display: none; width: 100%; flex-direction: column; align-items: flex-start; }
  .nav.open { display: flex; }
  .hero .container, .grid-3, .footer-grid, .cta-strip { grid-template-columns: 1fr; }
  .demo-hsearch { flex: 1 1 100%; max-width: none; }
  .header-actions { margin-left: 0; width: 100%; }
  .main-nav { top: 0; }
  .tabs { flex-direction: column; }
}