/* NFTWhy Design System — Cyber-Digital NFT Academy (light, airy) */
/* Pale canvas · dark ink · restrained cyan + violet accents · dark footer */
/* Sora (display) · Inter (body) · Space Mono (labels) */


:root {
  /* Surfaces — light */
  --bg: #f3f5fc;
  --bg-deep: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8f9fe;
  --bg-glass: rgba(255, 255, 255, 0.72);
  --surface-low: #eef1fa;
  --surface-high: #e5e8f5;

  /* Footer / dark anchor */
  --ink: #14162e;

  /* Lines */
  --border: rgba(28, 30, 60, 0.10);
  --border-strong: rgba(0, 150, 170, 0.36);
  --border-hover: #00aeb8;
  --outline-variant: rgba(28, 30, 60, 0.14);

  /* Ink */
  --text: #2c2f4a;
  --text-muted: #565b78;
  --text-dim: #8388a6;
  --heading: #16182e;

  /* Accents — readable on light */
  --accent: #00b3c4;            /* teal-cyan: borders, icons, hovers */
  --accent-bright: #00d4e0;     /* button fill (with dark ink text) */
  --accent-light: #0a7d86;      /* links — AA on white */
  --accent-2: #6d3bd1;          /* electric violet */
  --accent-2-deep: #4a1f9e;
  --lavender: #8b7fd0;
  --accent-gradient: linear-gradient(135deg, #00cfe0 0%, #00b3c4 100%);
  --text-gradient: linear-gradient(90deg, #1f9bd1 0%, #6d57c0 100%);
  --on-accent: #00343a;         /* dark ink on cyan fills */

  /* Semantic (AA on light) */
  --success: #0a9e80;
  --warning: #b06f00;
  --danger: #c0392b;
  --info: #0a7d86;

  /* Shape — soft-tech */
  --radius: 12px;
  --radius-sm: 4px;
  --radius-lg: 12px;

  /* Depth — soft, tinted (never pure black) */
  --shadow: 0 10px 30px rgba(40, 50, 110, 0.10);
  --shadow-glow: 0 8px 24px rgba(0, 179, 196, 0.22);
  --shadow-glow-soft: 0 6px 20px rgba(40, 50, 110, 0.08);

  /* Type */
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-display: 'Sora', 'Inter', sans-serif;
  --font-mono: 'Space Mono', 'JetBrains Mono', ui-monospace, monospace;

  --max-w: 1280px;
  --max-w-article: 820px;
  --transition: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font);
  color: var(--text);
  background-color: var(--bg);
  background-image:
    radial-gradient(680px 480px at 8% -8%, rgba(0, 179, 196, 0.10), transparent 70%),
    radial-gradient(620px 460px at 100% -4%, rgba(109, 59, 209, 0.08), transparent 72%),
    linear-gradient(to right, rgba(28, 40, 90, 0.025) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(28, 40, 90, 0.025) 1px, transparent 1px);
  background-size: auto, auto, 46px 46px, 46px 46px;
  background-attachment: fixed, fixed, scroll, scroll;
  line-height: 1.6;
  font-size: 16px;
  min-height: 100vh;
  overflow-x: hidden;
}

.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }
a { color: var(--accent-light); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-2-deep); }
img { max-width: 100%; height: auto; }
::selection { background: rgba(0, 179, 196, 0.22); }

h1, h2, h3, h4 { font-family: var(--font-display); color: var(--heading); }

/* ==================== HEADER ==================== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(243, 245, 252, 0.82);
  backdrop-filter: saturate(140%) blur(14px);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid var(--border);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 66px; }
.brand {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--heading);
  font-family: var(--font-display); font-weight: 800; font-size: 1.18rem; letter-spacing: -0.01em;
}
.brand:hover { color: var(--accent-light); }
.brand-mark { width: 34px; height: 34px; max-width: 34px; max-height: 34px; flex-shrink: 0; overflow: hidden; }
.brand-mark svg, .brand-mark img { width: 100%; height: 100%; object-fit: contain; }
.brand-name { white-space: nowrap; }

.site-nav { display: flex; align-items: center; gap: 4px; list-style: none; flex-wrap: wrap; }
.nav-text {
  padding: 7px 13px; border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-family: var(--font-mono); font-size: 0.74rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  transition: all var(--transition);
}
.nav-text:hover { color: var(--accent-light); background: var(--surface-low); }
.nav-cta {
  display: inline-flex; align-items: center; gap: 6px; padding: 9px 18px;
  background: var(--accent-bright); color: var(--on-accent) !important;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono); font-weight: 700; font-size: 0.74rem;
  text-transform: uppercase; letter-spacing: 0.07em;
  box-shadow: var(--shadow-glow-soft);
  transition: box-shadow var(--transition), transform var(--transition);
}
.nav-cta .nav-text { padding: 0; color: var(--on-accent); }
.nav-cta:hover { box-shadow: var(--shadow-glow); transform: translateY(-1px); }
.nav-cta:active { transform: scale(0.97); }

.lang-switch { position: relative; }
.lang-switch summary {
  cursor: pointer; padding: 7px 12px; border-radius: var(--radius-sm);
  font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em;
  color: var(--text-muted); list-style: none;
}
.lang-switch summary::-webkit-details-marker { display: none; }
.lang-switch summary:hover { color: var(--accent-light); }
.lang-dropdown {
  position: absolute; right: 0; top: 120%;
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 8px 4px; min-width: 150px;
  box-shadow: var(--shadow); display: flex; flex-direction: column; z-index: 200;
}
.lang-dropdown a { padding: 7px 14px; border-radius: var(--radius-sm); color: var(--text-muted); font-size: 0.86rem; }
.lang-dropdown a:hover { background: var(--surface-low); color: var(--accent-light); }

/* ==================== HERO (minor-lang index) ==================== */
.hero { padding: 84px 0 60px; text-align: center; position: relative; }
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 5vw, 3.6rem); font-weight: 800; color: var(--heading);
  line-height: 1.1; letter-spacing: -0.02em; margin-bottom: 18px; text-wrap: balance;
}
.hero .subtitle { font-size: 1.12rem; color: var(--text-muted); max-width: 620px; margin: 0 auto 32px; line-height: 1.6; }
.hero-cta-group { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* Buttons */
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px; padding: 13px 28px;
  background: var(--accent-bright); color: var(--on-accent);
  font-family: var(--font-mono); font-weight: 700; font-size: 0.82rem;
  text-transform: uppercase; letter-spacing: 0.07em;
  border-radius: var(--radius-sm); border: none; cursor: pointer;
  box-shadow: var(--shadow-glow);
  transition: box-shadow var(--transition), transform var(--transition);
}
.btn-primary:hover { box-shadow: 0 10px 28px rgba(0,179,196,0.34); transform: translateY(-2px); color: var(--on-accent); }
.btn-primary:active { transform: scale(0.98); }
.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px; padding: 13px 28px;
  background: transparent; color: var(--accent-light);
  font-family: var(--font-mono); font-weight: 700; font-size: 0.82rem;
  text-transform: uppercase; letter-spacing: 0.07em;
  border-radius: var(--radius-sm); border: 1px solid var(--accent); cursor: pointer;
  transition: all var(--transition);
}
.btn-secondary:hover { background: rgba(0,179,196,0.08); border-color: var(--accent-light); }

/* Article header */
.article-header { padding: 64px 0 30px; border-bottom: 1px solid var(--border); }
.article-header h1 {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4vw, 2.8rem); font-weight: 800; color: var(--heading);
  line-height: 1.18; letter-spacing: -0.015em; text-wrap: balance;
}
.article-header h1 small { display: block; margin-top: 10px; font-family: var(--font); font-size: 0.5em; font-weight: 400; letter-spacing: 0; line-height: 1.4; color: var(--text-muted); }
.article-meta { display: flex; gap: 16px; margin-top: 14px; color: var(--text-dim); font-family: var(--font-mono); font-size: 0.78rem; letter-spacing: 0.02em; }
.article-meta a { color: var(--accent-light); }

/* ==================== CARDS ==================== */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; margin: 32px 0; }
.card {
  position: relative; overflow: hidden;
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 28px;
  box-shadow: var(--shadow-glow-soft);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.card::before {
  content: ""; position: absolute; inset: 0; border-radius: inherit; padding: 1px;
  background: linear-gradient(135deg, rgba(0,179,196,0.45) 0%, rgba(0,179,196,0.06) 50%, rgba(109,59,209,0.30) 100%);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude; pointer-events: none; opacity: 0.6;
  transition: opacity var(--transition);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--border-strong); }
.card:hover::before { opacity: 1; }
.card-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 52px; height: 52px; margin-bottom: 16px; border-radius: 50%;
  background: rgba(0, 179, 196, 0.10); border: 1px solid rgba(0,179,196,0.22);
  font-size: 1.5rem; transition: box-shadow var(--transition);
}
.card:hover .card-icon { box-shadow: 0 0 0 4px rgba(0,179,196,0.10); }
.card h3 { font-family: var(--font-display); font-size: 1.18rem; font-weight: 600; color: var(--heading); margin-bottom: 8px; }
.card p { color: var(--text-muted); font-size: 0.95rem; line-height: 1.6; }
.card-link {
  display: inline-flex; align-items: center; gap: 4px; margin-top: 16px;
  font-family: var(--font-mono); font-weight: 700; font-size: 0.74rem;
  text-transform: uppercase; letter-spacing: 0.05em; color: var(--accent-light);
}
.card-link::after { content: ' →'; transition: transform var(--transition); }
.card:hover .card-link::after { transform: translateX(4px); }

/* Path cards (3-step sequence) */
.path-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; margin: 32px 0; }
.path-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 28px 24px; text-align: center; box-shadow: var(--shadow-glow-soft);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.path-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--border-strong); }
.path-step {
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(0,179,196,0.08); border: 1.5px solid var(--accent);
  color: var(--accent-light); font-family: var(--font-mono); font-weight: 700; font-size: 1.05rem;
  display: inline-flex; align-items: center; justify-content: center; margin-bottom: 14px;
}
.path-card h3 { font-family: var(--font-display); font-size: 1.08rem; color: var(--heading); margin-bottom: 8px; }
.path-card p { color: var(--text-muted); font-size: 0.9rem; }

/* ==================== ARTICLE BODY ==================== */
.article-body { padding: 44px 0 64px; }
.article-body h2 {
  font-family: var(--font-display); font-size: 1.55rem; font-weight: 700; color: var(--heading);
  margin: 44px 0 16px; padding-bottom: 10px; letter-spacing: -0.01em;
  border-bottom: 1px solid var(--border); position: relative;
}
.article-body h2::after { content: ''; position: absolute; left: 0; bottom: -1px; width: 56px; height: 2px; background: var(--accent); }
.article-body h3 { font-family: var(--font-display); font-size: 1.18rem; font-weight: 600; color: var(--heading); margin: 28px 0 12px; }
.article-body p { margin-bottom: 16px; }
.article-body ul, .article-body ol { margin: 0 0 20px 24px; }
.article-body li { margin-bottom: 8px; }
.article-body strong { color: var(--heading); }
.article-body a { text-decoration: underline; text-decoration-color: rgba(0,179,196,0.5); text-underline-offset: 2px; }

/* Article banner (topic visual placed directly on the page, no panel) */
.article-banner {
  margin: 8px 0 30px;
  display: flex; align-items: center; justify-content: center;
}
.article-banner img {
  height: 260px; width: auto; max-width: 100%; object-fit: contain;
  filter: drop-shadow(0 12px 22px rgba(20, 30, 80, 0.20));
}
@media (max-width: 768px) { .article-banner img { height: 180px; } }

/* Concept box */
.concept-box {
  background: linear-gradient(135deg, rgba(0,179,196,0.07), rgba(109,59,209,0.05));
  border: 1px solid var(--border-strong); border-radius: var(--radius-lg);
  padding: 24px; margin: 24px 0;
}
.concept-box h3 { margin: 0 0 8px; border: none; padding: 0; font-size: 1.1rem; color: var(--accent-light); }

/* Analogy box */
.analogy-box { background: rgba(109, 59, 209, 0.06); border: 1px solid rgba(109,59,209,0.22); border-radius: var(--radius-sm); padding: 16px 20px; margin: 20px 0; }

/* Callouts */
.callout { border-radius: var(--radius-sm); padding: 16px 20px; margin: 20px 0; font-size: 0.95rem; border: 1px solid; }
.callout-warning { background: rgba(176, 111, 0, 0.07); border-color: rgba(176, 111, 0, 0.30); }
.callout-danger  { background: rgba(192, 57, 43, 0.06); border-color: rgba(192, 57, 43, 0.28); }
.callout-info    { background: rgba(0, 179, 196, 0.07); border-color: rgba(0, 179, 196, 0.28); }
.callout-success { background: rgba(10, 158, 128, 0.07); border-color: rgba(10, 158, 128, 0.28); }

/* TOC */
details.toc { background: var(--surface-low); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 20px; margin: 24px 0; }
details.toc summary {
  cursor: pointer; font-family: var(--font-mono); font-weight: 700; color: var(--accent-light);
  font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.05em; list-style: none;
}
details.toc summary::-webkit-details-marker { display: none; }
details.toc summary::before { content: '> '; color: var(--accent); }
details.toc ol { margin: 14px 0 0 20px; }
details.toc li { margin-bottom: 5px; }
details.toc a { color: var(--text-muted); }
details.toc a:hover { color: var(--accent-light); }

/* FAQ */
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); margin: 12px 0; overflow: hidden; background: var(--bg-card); }
.faq-item summary {
  cursor: pointer; padding: 15px 18px; font-weight: 600; color: var(--heading);
  background: var(--surface-low); list-style: none; font-size: 0.97rem; transition: background var(--transition);
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::before { content: '+ '; color: var(--accent-light); font-family: var(--font-mono); }
.faq-item[open] summary::before { content: '− '; }
.faq-item summary:hover { background: var(--surface-high); }
.faq-answer { padding: 15px 18px; color: var(--text-muted); font-size: 0.95rem; line-height: 1.7; border-top: 1px solid var(--border); }

/* Tables */
.table-wrap { overflow-x: auto; margin: 20px 0; border-radius: var(--radius); border: 1px solid var(--border); }
.compare-table { width: 100%; border-collapse: collapse; font-size: 0.9rem; background: var(--bg-card); }
.compare-table th {
  background: var(--surface-low); color: var(--accent-light);
  font-family: var(--font-mono); font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.03em;
  padding: 13px 16px; text-align: left; font-weight: 700; border-bottom: 2px solid var(--accent);
}
.compare-table td { padding: 11px 16px; border-bottom: 1px solid var(--border); }
.compare-table tr:last-child td { border-bottom: none; }
.compare-table tbody tr:hover { background: var(--surface-low); }

/* Chain flow */
.chain-flow { display: flex; align-items: center; gap: 10px; overflow-x: auto; padding: 16px 0; flex-wrap: wrap; justify-content: center; }
.chain-block { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 18px; min-width: 140px; text-align: center; box-shadow: var(--shadow-glow-soft); }
.chain-block h4 { font-family: var(--font-display); color: var(--heading); font-size: 0.95rem; margin-bottom: 4px; }
.chain-block p { color: var(--text-muted); font-size: 0.85rem; margin: 0; }
.chain-arrow { color: var(--accent); font-size: 1.4rem; font-weight: 700; }

/* Related articles */
.related-articles { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; margin: 32px 0 16px; }
.related-link {
  display: flex; align-items: center; gap: 12px; padding: 15px 16px;
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-glow-soft);
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}
.related-link:hover { border-color: var(--border-strong); transform: translateX(4px); box-shadow: var(--shadow-glow); }
.rl-icon { font-size: 1.3rem; flex-shrink: 0; }
.rl-title { font-weight: 600; font-size: 0.9rem; color: var(--heading); }

/* Trust / safety notes */
.trust-note { margin: 40px 0 0; padding: 16px 18px; border-top: 1px solid var(--border); font-size: 0.84rem; color: var(--text-dim); }
.site-safety-note {
  background: rgba(192, 57, 43, 0.05); border: 1px solid rgba(192, 57, 43, 0.18);
  border-radius: var(--radius); padding: 14px 18px; font-size: 0.85rem; color: var(--text-muted); margin: 20px 0;
}
.site-safety-note a { color: var(--accent-light); }

/* ==================== FOOTER (dark anchor) ==================== */
.site-footer { border-top: 1px solid var(--ink); background: var(--ink); padding: 38px 0; text-align: center; position: relative; z-index: 1; }
.footer-bottom { color: rgba(224, 224, 255, 0.6); font-family: var(--font-mono); font-size: 0.8rem; letter-spacing: 0.02em; }
.footer-bottom span, .footer-bottom p { color: rgba(224, 224, 255, 0.75); }
.footer-links { margin-top: 10px; display: flex; gap: 4px; justify-content: center; flex-wrap: wrap; }
.footer-links a {
  color: rgba(224, 224, 255, 0.6); margin: 0 12px; font-family: var(--font-mono); font-size: 0.78rem;
  text-transform: uppercase; letter-spacing: 0.04em;
}
.footer-links a:hover { color: #00d4e0; }

/* Cookie consent banner */
.cookie-banner {
  position: fixed; left: 16px; right: 16px; bottom: 16px; z-index: 200;
  max-width: 720px; margin: 0 auto;
  display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  background: var(--ink); color: rgba(224,224,255,0.92);
  border: 1px solid var(--border-strong); border-radius: var(--radius);
  padding: 14px 18px; box-shadow: 0 12px 40px rgba(3,5,20,0.5); font-size: 0.86rem;
}
.cookie-banner .cb-text { flex: 1 1 240px; line-height: 1.5; }
.cookie-banner .cb-btns { display: flex; gap: 8px; flex-shrink: 0; }
.cookie-banner button {
  font-family: var(--font-mono); font-size: 0.72rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.05em;
  padding: 8px 16px; border-radius: var(--radius-sm); cursor: pointer; border: 1px solid;
}
.cookie-banner .cb-yes { background: var(--accent-bright); color: var(--on-accent); border-color: var(--accent-bright); }
.cookie-banner .cb-no { background: transparent; color: rgba(224,224,255,0.75); border-color: rgba(224,224,255,0.3); }
@media (max-width: 520px) { .cookie-banner { flex-direction: column; align-items: stretch; } .cookie-banner .cb-btns { justify-content: flex-end; } }

/* ==================== RESPONSIVE ==================== */
@media (max-width: 768px) {
  .site-header .container { height: auto; flex-wrap: wrap; padding: 12px 16px; gap: 8px; }
  .site-nav { gap: 2px; }
  .nav-text { padding: 5px 9px; font-size: 0.68rem; }
  .hero { padding: 52px 0 40px; }
  .container { padding: 0 16px; }
  .card-grid, .path-grid { grid-template-columns: 1fr; }
  .chain-flow { flex-direction: column; }
  .chain-arrow { transform: rotate(90deg); }
  .article-header { padding: 44px 0 22px; }
  .article-body h2 { font-size: 1.32rem; }
}
@media (max-width: 480px) {
  body { font-size: 15px; }
  .btn-primary, .btn-secondary { padding: 12px 22px; font-size: 0.78rem; }
}

/* ==================== MOTION ==================== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}