/* ============================================================
   YES Lab Whitepaper — layout (cyberpunk / dark, matches homepage)
   Depends on assets/colors_and_type.css for design tokens.
   ============================================================ */

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg-void);
  color: var(--fg-1);
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* Shared background */
.bg-circuit {
  position: fixed; inset: 0; z-index: -2;
  background: url('assets/circuit-pattern.svg');
  background-size: 280px 280px;
  opacity: 0.08;
  pointer-events: none;
}
.bg-glow {
  position: fixed; inset: 0; z-index: -1; pointer-events: none; overflow: hidden;
}
.bg-glow::before, .bg-glow::after {
  content: ""; position: absolute; width: 480px; height: 480px; border-radius: 50%;
  filter: blur(140px); opacity: 0.45;
}
.bg-glow::before { background: var(--neon-cyan-30); top: -120px; left: -120px; }
.bg-glow::after  { background: var(--neon-blue-30); top: 280px; right: -160px; }

.container { max-width: 1280px; margin: 0 auto; padding: 0 32px; }
@media (max-width: 720px) { .container { padding: 0 20px; } }

/* ============================================================
   Navbar (mirrors homepage)
   ============================================================ */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  height: 64px;
  background: var(--bg-glass);
  backdrop-filter: var(--blur-glass);
  -webkit-backdrop-filter: var(--blur-glass);
  border-bottom: 1px solid var(--border-default);
}
.nav-inner {
  height: 100%; display: flex; align-items: center; justify-content: space-between;
}
.brand {
  display: flex; align-items: center;
  gap: 12px;
  text-decoration: none;
  height: 44px;
}
.brand-icon {
  height: 40px; width: auto;
  object-fit: contain;
  mix-blend-mode: screen;
  filter: drop-shadow(0 0 8px var(--neon-cyan-30));
  transition: filter var(--dur-base) var(--ease-out);
}
.brand-text {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-wide);
  color: var(--fg-1);
  text-shadow: 0 0 12px var(--neon-cyan-30);
  transition: color var(--dur-base) var(--ease-out), text-shadow var(--dur-base) var(--ease-out);
}
.brand:hover .brand-icon {
  filter: drop-shadow(0 0 16px var(--neon-cyan-50));
}
.brand:hover .brand-text {
  color: var(--neon-cyan);
  text-shadow: 0 0 18px var(--neon-cyan-50);
}
.brand-banner {
  height: 44px; width: auto;
  object-fit: contain;
  mix-blend-mode: screen;
  filter: drop-shadow(0 0 10px var(--neon-cyan-30));
  transition: filter var(--dur-base) var(--ease-out);
}
.brand:hover .brand-banner {
  filter: drop-shadow(0 0 18px var(--neon-cyan-50));
}
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a {
  font-family: var(--font-mono);
  font-size: 12px; font-weight: var(--fw-medium);
  letter-spacing: var(--ls-wider);
  color: var(--fg-3);
  transition: color var(--dur-fast) var(--ease-out);
  text-transform: uppercase;
}
.nav-links a:hover,
.nav-links a.is-active { color: var(--neon-cyan); }
.nav-right { display: flex; align-items: center; gap: 12px; }
.lang-toggle {
  font-family: var(--font-mono); font-size: 11px;
  padding: 5px 10px;
  border: 1px solid var(--neon-cyan-30);
  border-radius: var(--radius);
  color: var(--neon-cyan);
  background: var(--bg-glass);
  letter-spacing: var(--ls-wider);
  display: inline-flex; align-items: center;
}
.lang-toggle:hover { background: var(--neon-cyan-10); }
.nav-cta {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 8px 14px;
  font-family: var(--font-mono); font-size: 11px;
  letter-spacing: var(--ls-wider);
  color: var(--neon-cyan);
  border: 1px solid var(--neon-cyan-50);
  background: var(--neon-cyan-10);
  border-radius: var(--radius);
  transition: all var(--dur-base) var(--ease-out);
}
.nav-cta:hover {
  background: var(--neon-cyan);
  color: var(--fg-on-neon);
  box-shadow: var(--glow-cyan-md);
}
@media (max-width: 880px) {
  .nav-links { display: none; }
}

/* ============================================================
   Scroll-progress bar (top of viewport, below nav)
   ============================================================ */
.scroll-progress {
  position: fixed;
  top: 64px; left: 0; right: 0;
  height: 2px; z-index: 49;
  background: var(--bg-white-04);
}
.scroll-progress span {
  display: block; height: 100%;
  width: calc(var(--scroll-progress, 0) * 1%);
  background: linear-gradient(90deg, var(--neon-cyan), var(--neon-blue));
  box-shadow: 0 0 12px var(--neon-cyan-50);
  transition: width 120ms linear;
}

/* ============================================================
   Buttons — match homepage btn primitive
   ============================================================ */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 14px 22px;
  font-family: var(--font-mono); font-size: 13px; font-weight: var(--fw-medium);
  letter-spacing: var(--ls-wider);
  text-decoration: none;
  border-radius: var(--radius);
  transition: all var(--dur-base) var(--ease-out);
  cursor: pointer;
  border: 1px solid;
}
.btn-primary {
  color: var(--neon-cyan);
  border-color: var(--neon-cyan-50);
  background: var(--neon-cyan-10);
}
.btn-primary:hover {
  color: var(--fg-on-neon);
  background: var(--neon-cyan);
  box-shadow: var(--glow-cyan-md);
}
.btn-ghost {
  color: var(--fg-2);
  border-color: var(--border-strong);
  background: transparent;
}
.btn-ghost:hover {
  color: var(--fg-1);
  border-color: var(--fg-1);
  background: var(--bg-white-05);
}

/* ============================================================
   Hero
   ============================================================ */
.whitepaper-shell {
  padding-top: 96px;
  padding-bottom: 80px;
}

.whitepaper-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(280px, 0.8fr);
  gap: 48px;
  align-items: center;
  padding: 56px 0 64px;
}
@media (max-width: 980px) {
  .whitepaper-hero { grid-template-columns: 1fr; gap: 36px; }
}

.whitepaper-hero .eyebrow {
  display: inline-block;
  margin-bottom: 24px;
}

.whitepaper-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4.6vw, 4rem);
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-tight);
  line-height: 1;
  margin: 0 0 18px;
  color: var(--fg-1);
}
html[lang="zh-CN"] .whitepaper-hero h1 {
  font-size: clamp(2.1rem, 4.2vw, 3.6rem);
  line-height: 1.05;
}

.whitepaper-subtitle {
  margin: 0 0 22px;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  letter-spacing: var(--ls-wider);
  color: var(--neon-green);
}

.whitepaper-summary {
  max-width: 640px;
  margin: 0 0 32px;
  color: var(--fg-2);
  font-size: var(--fs-lg);
  line-height: var(--lh-relaxed);
}

.whitepaper-actions {
  display: flex; flex-wrap: wrap; gap: 14px;
}

/* Hero right — info card with orbit */
.whitepaper-visual {
  position: relative;
  min-height: 340px;
  border: 1px solid var(--neon-cyan-30);
  border-radius: var(--radius-xl);
  background:
    radial-gradient(ellipse at top right, var(--neon-cyan-10), transparent 60%),
    rgba(8, 8, 10, 0.7);
  box-shadow: 0 0 50px var(--neon-cyan-20), 0 30px 80px rgba(0,0,0,0.6);
  overflow: hidden;
  backdrop-filter: blur(10px);
}
.whitepaper-visual::before {
  position: absolute; inset: 14px; content: "";
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  pointer-events: none;
}
.whitepaper-visual::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(0,243,255,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,243,255,0.06) 1px, transparent 1px);
  background-size: 36px 36px;
  pointer-events: none;
  mask-image: radial-gradient(ellipse at center, black, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse at center, black, transparent 80%);
}

.whitepaper-orbit {
  position: absolute;
  inset: 18px 18px auto auto;
  width: min(92%, 380px);
  height: auto;
  opacity: 0.6;
  filter: drop-shadow(0 0 18px var(--neon-cyan-30));
}
.whitepaper-orbit path {
  fill: none;
  stroke: url("#whitepaper-orbit-line");
  stroke-width: 1.4;
  stroke-dasharray: 9 11;
}
.whitepaper-orbit circle {
  fill: var(--bg-void);
  stroke: var(--neon-cyan);
  stroke-width: 1.8;
}

.whitepaper-card {
  position: absolute;
  left: 22px;
  right: 22px;
  bottom: 22px;
  display: grid; gap: 8px;
  padding: 22px 24px;
  border: 1px solid var(--neon-cyan-30);
  border-radius: var(--radius-md);
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(14px);
}
.whitepaper-card span {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-widest);
  text-transform: uppercase;
  color: var(--neon-cyan);
}
.whitepaper-card strong {
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 2vw, 1.8rem);
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-tight);
  color: var(--fg-1);
}
.whitepaper-card em {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-wide);
  color: var(--fg-4);
  font-style: normal;
}

/* ============================================================
   Layout — TOC + Article
   ============================================================ */
.whitepaper-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 34px;
  align-items: start;
  padding-bottom: 96px;
}
@media (max-width: 980px) {
  .whitepaper-layout { grid-template-columns: 1fr; }
}

.whitepaper-toc {
  position: sticky;
  top: 88px;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 20px;
  background: rgba(10, 10, 12, 0.7);
  backdrop-filter: blur(10px);
}
@media (max-width: 980px) {
  .whitepaper-toc { position: static; }
}
.whitepaper-toc > p {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-widest);
  color: var(--neon-cyan);
  text-transform: uppercase;
  border-left: 2px solid var(--neon-cyan);
  padding-left: 10px;
}
.whitepaper-toc nav {
  display: grid; gap: 2px;
}
.whitepaper-toc a {
  display: block;
  padding: 8px 10px;
  border-radius: var(--radius);
  color: var(--fg-3);
  font-family: var(--font-sans);
  font-size: 13px;
  line-height: 1.4;
  border-left: 2px solid transparent;
  transition: all var(--dur-fast) var(--ease-out);
}
.whitepaper-toc a:hover {
  color: var(--fg-1);
  background: var(--bg-white-05);
}
.whitepaper-toc a.is-active {
  color: var(--neon-cyan);
  background: var(--neon-cyan-10);
  border-left-color: var(--neon-cyan);
}
.whitepaper-toc .toc-level-3 {
  padding-left: 22px;
  font-size: 12px;
  color: var(--fg-4);
}
.whitepaper-toc .toc-level-3.is-active { padding-left: 22px; }

/* ============================================================
   Article — prose
   ============================================================ */
.whitepaper-article {
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: clamp(28px, 4vw, 56px);
  background: rgba(8, 8, 10, 0.6);
  backdrop-filter: blur(10px);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.35);
}
.whitepaper-article > :first-child { margin-top: 0; }

.whitepaper-article h2,
.whitepaper-article h3,
.whitepaper-article h4 {
  scroll-margin-top: 100px;
}

.whitepaper-article h2 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 2.6vw, 2rem);
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-tight);
  color: var(--fg-1);
  line-height: 1.2;
  margin: 56px 0 20px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-subtle);
  position: relative;
}
.whitepaper-article h2::before {
  content: "";
  display: inline-block;
  width: 12px; height: 12px;
  margin-right: 12px;
  vertical-align: 1px;
  background: var(--neon-cyan);
  box-shadow: 0 0 10px var(--neon-cyan-50);
  border-radius: 2px;
}

.whitepaper-article h3 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-tight);
  color: var(--neon-cyan);
  margin: 36px 0 14px;
}

.whitepaper-article p,
.whitepaper-article li {
  color: var(--fg-2);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.78;
}
.whitepaper-article p { margin: 0 0 18px; }

.whitepaper-article ul,
.whitepaper-article ol {
  display: grid; gap: 12px;
  margin: 18px 0 26px;
  padding-left: 22px;
}
.whitepaper-article li::marker { color: var(--neon-green); }

.whitepaper-article strong {
  color: var(--fg-1);
  font-weight: var(--fw-semibold);
}
.whitepaper-article em {
  color: var(--neon-cyan);
  font-style: normal;
}

.whitepaper-article code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--neon-cyan);
  background: var(--bg-white-05);
  border: 1px solid var(--border-subtle);
  padding: 0.1em 0.4em;
  border-radius: var(--radius-sm);
}

.whitepaper-article hr {
  height: 1px; border: 0; margin: 38px 0;
  background: linear-gradient(90deg, transparent, var(--neon-cyan-30), transparent);
}

.yee-link {
  color: inherit;
  text-decoration: underline dotted;
  text-decoration-color: var(--fg-5);
  text-underline-offset: 3px;
  transition: color var(--dur-fast) var(--ease-out), text-decoration-color var(--dur-fast) var(--ease-out);
}
.yee-link:hover {
  color: var(--neon-cyan);
  text-decoration-color: var(--neon-cyan);
}

/* ============================================================
   Footer
   ============================================================ */
.whitepaper-footer {
  border-top: 1px solid var(--border-default);
  padding: 36px 0;
  margin-top: 40px;
}
.whitepaper-footer .container {
  display: flex; justify-content: space-between; align-items: center;
  gap: 16px; flex-wrap: wrap;
}
.whitepaper-footer .foot-brand {
  display: flex; flex-direction: column; gap: 4px;
}
.whitepaper-footer .foot-brand strong {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-wide);
  color: var(--fg-1);
}
.whitepaper-footer .foot-brand span {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-wide);
  color: var(--fg-4);
}
.whitepaper-footer .foot-home {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: var(--ls-wider);
  color: var(--fg-3);
  text-transform: uppercase;
  text-decoration: none;
  border: 1px solid var(--border-default);
  padding: 8px 14px;
  border-radius: var(--radius);
  transition: all var(--dur-base) var(--ease-out);
}
.whitepaper-footer .foot-home:hover {
  color: var(--neon-cyan);
  border-color: var(--neon-cyan-50);
  background: var(--neon-cyan-10);
}

/* ============================================================
   Responsive tweaks
   ============================================================ */
@media (max-width: 640px) {
  .whitepaper-shell { padding-top: 80px; }
  .whitepaper-hero { padding: 36px 0 44px; }
  .whitepaper-actions .btn { width: 100%; justify-content: center; }
  .whitepaper-visual { min-height: 280px; }
  .whitepaper-article { padding: 22px; }
}