/* ==========================================================================
   Roban AI — site styles
   Dark, restrained, pre-launch. Tokens and rules are documented in DESIGN.md.
   ========================================================================== */

:root {
  /* Brand */
  --red: #e51717;
  --red-hover: #f52a2a;
  --red-press: #c21212;
  --red-bright: #ff4d4d;
  --red-wash: rgba(229, 23, 23, 0.14);
  --red-glow: rgba(229, 23, 23, 0.32);

  /* Surfaces */
  --bg: #0d0d10;
  --bg-raise: #131317;
  --panel: rgba(23, 23, 28, 0.92);
  --line: rgba(255, 255, 255, 0.08);
  --line-strong: rgba(255, 255, 255, 0.16);

  /* Text */
  --ink: #f5f5f6;
  --ink-dim: #c9c9cf;
  --muted: #94949c;
  --faint: #6d6d76;

  /* Shape & motion */
  --radius: 12px;
  --radius-pill: 999px;
  --ease: cubic-bezier(0.32, 0.72, 0, 1);
  --t-fast: 0.18s;
  --t-med: 0.32s;
  --shadow-menu: 0 18px 48px rgba(0, 0, 0, 0.55);
  --shadow-card: 0 30px 80px rgba(0, 0, 0, 0.55);

  /* Layout */
  --shell: 1120px;
  --header-h: 64px;
}

/* ============ Base ============ */

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: "Inter", "SF Pro Text", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: clip;
}

/* ---- Language ---- */

html.lang-en [data-lang="zh"] { display: none !important; }
html.lang-zh [data-lang="en"] { display: none !important; }

.lang-toggle {
  position: relative;
  width: 64px;
  height: 30px;
  padding: 3px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.03);
  display: flex;
  align-items: stretch;
  cursor: pointer;
  transition: border-color var(--t-fast) ease;
}

.lang-toggle:hover { border-color: rgba(255, 255, 255, 0.32); }

.lang-toggle .knob {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 28px;
  height: 22px;
  border-radius: var(--radius-pill);
  background: #f0f0f2;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.45);
  transition: transform 0.28s var(--ease);
  z-index: 1;
  pointer-events: none;
}

html.lang-zh .lang-toggle .knob { transform: translateX(30px); }

.lg-opt {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1;
  color: var(--muted);
  z-index: 2;
  pointer-events: none;
  transition: color var(--t-fast) ease;
}

html.lang-en .lg-en { color: #16161a; }
html.lang-zh .lg-zh { color: #16161a; }

/* Film grain over everything; purely decorative */
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  opacity: 0.045;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)'/%3E%3C/svg%3E");
}

::selection { background: rgba(229, 23, 23, 0.38); color: #fff; }

a { color: inherit; }

img { max-width: 100%; }

:focus-visible {
  outline: 2px solid var(--red-bright);
  outline-offset: 3px;
  border-radius: 4px;
}

.shell {
  width: min(var(--shell), calc(100% - 48px));
  margin-inline: auto;
}

main, .site-footer { position: relative; z-index: 1; }

/* ============ Atmosphere ============ */

#starfield {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.ambient {
  position: fixed;
  z-index: 0;
  pointer-events: none;
  border-radius: 50%;
}

.ambient-a {
  top: -18vh;
  right: -12vw;
  width: 60vw;
  aspect-ratio: 1;
  background: radial-gradient(circle at 50% 50%, rgba(229, 23, 23, 0.13), rgba(229, 23, 23, 0.05) 45%, transparent 70%);
  animation: ambient-drift 18s ease-in-out infinite alternate;
}

.ambient-b {
  bottom: -24vh;
  left: -14vw;
  width: 48vw;
  aspect-ratio: 1;
  background: radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.035), transparent 65%);
  animation: ambient-drift 24s ease-in-out infinite alternate-reverse;
}

@keyframes ambient-drift {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to { transform: translate3d(-2.5%, 2.5%, 0) scale(1.06); }
}

/* ============ Header ============ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: rgba(13, 13, 16, 0.72);
  backdrop-filter: blur(14px) saturate(1.2);
  -webkit-backdrop-filter: blur(14px) saturate(1.2);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--ink);
}

.brand-mark {
  width: 30px;
  height: 30px;
  display: block;
  border-radius: 50%;
}

.brand-name {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand-name b { color: var(--red-bright); font-weight: 700; }

.header-nav {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* ---- Dropdown ---- */

.menu { position: relative; }

.menu-trigger {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 38px;
  padding: 0 14px 0 16px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: transparent;
  color: var(--ink-dim);
  font-size: 14px;
  font-weight: 600;
  font-family: inherit;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition: border-color var(--t-fast) ease, color var(--t-fast) ease, background var(--t-fast) ease;
}

.menu-trigger:hover {
  border-color: rgba(255, 255, 255, 0.32);
  color: var(--ink);
  background: rgba(255, 255, 255, 0.04);
}

.menu-trigger[aria-expanded="true"] {
  border-color: rgba(255, 255, 255, 0.32);
  color: var(--ink);
  background: rgba(255, 255, 255, 0.06);
}

.menu-caret { transition: transform var(--t-med) var(--ease); }

.menu-trigger[aria-expanded="true"] .menu-caret { transform: rotate(180deg); }

.menu-panel {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 216px;
  padding: 6px;
  background: var(--panel);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  box-shadow: var(--shadow-menu);
  visibility: hidden;
  opacity: 0;
  transform: translateY(-4px) scale(0.985);
  transform-origin: top right;
  transition: opacity var(--t-med) var(--ease), transform var(--t-med) var(--ease), visibility 0s linear var(--t-med);
}

.menu-panel.open {
  visibility: visible;
  opacity: 1;
  transform: none;
  transition-delay: 0s;
}

.menu-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 9px 12px;
  border-radius: 8px;
  color: var(--ink-dim);
  font-size: 14px;
  font-weight: 560;
  text-decoration: none;
  transition: background var(--t-fast) ease, color var(--t-fast) ease;
}

.menu-item:hover { background: var(--red-wash); color: var(--ink); }

.menu-item-external { color: var(--muted); }
.menu-item-external:hover { color: var(--ink); }

/* ============ Buttons ============ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  height: 46px;
  padding: 0 24px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: 14.5px;
  font-weight: 640;
  letter-spacing: 0.005em;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition:
    background var(--t-fast) ease,
    border-color var(--t-fast) ease,
    color var(--t-fast) ease,
    box-shadow var(--t-med) var(--ease),
    transform var(--t-med) var(--ease);
}

.btn:active { transform: translateY(1px) scale(0.99); }

.btn-primary {
  background: var(--red);
  color: #fff;
  box-shadow: 0 10px 30px rgba(229, 23, 23, 0.28);
}

.btn-primary:hover {
  background: var(--red-hover);
  box-shadow: 0 14px 36px rgba(229, 23, 23, 0.38);
  transform: translateY(-1px);
}

.btn-primary:active { background: var(--red-press); }

.btn-ghost {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--ink-dim);
}

.btn-ghost:hover {
  border-color: rgba(255, 255, 255, 0.32);
  background: rgba(255, 255, 255, 0.04);
  color: var(--ink);
}

.btn-sm {
  height: 38px;
  padding: 0 16px;
  font-size: 13.5px;
}

/* ============ Labels ============ */

.dot {
  position: relative;
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--red-bright);
  box-shadow: 0 0 10px rgba(255, 77, 77, 0.75);
  flex: none;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0;
  padding: 7px 14px 7px 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.03);
  color: var(--ink-dim);
  font-size: 11.5px;
  font-weight: 650;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.status-pill .dot { width: 7px; height: 7px; animation: pulse 2.4s ease-out infinite; }

.status-pill .dot::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  border: 1px solid var(--red-bright);
  opacity: 0;
  animation: ping 2.4s ease-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.55; }
}

@keyframes ping {
  0% { transform: scale(0.6); opacity: 0.7; }
  70%, 100% { transform: scale(1.9); opacity: 0; }
}

.micro-label {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0 0 10px;
  color: var(--muted);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.micro-label .dot { width: 5px; height: 5px; }

/* ============ Hero ============ */

.hero {
  display: grid;
  grid-template-columns: 1.02fr 0.98fr;
  align-items: center;
  gap: clamp(32px, 5vw, 72px);
  padding: 64px 0 48px;
}

.hero-copy { min-width: 0; }

.hero h1 {
  margin: 22px 0 0;
  max-width: 620px;
  color: var(--ink);
  font-size: clamp(42px, 5.6vw, 74px);
  font-weight: 700;
  letter-spacing: -0.035em;
  line-height: 1.04;
  text-wrap: balance;
}

.hero h1 em {
  font-style: normal;
  color: var(--red-bright);
  text-shadow: 0 0 30px rgba(229, 23, 23, 0.3);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 34px;
}

/* ---- Hero visual ---- */

.hero-visual {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 460px;
}

.orb-wrap,
.card-wrap {
  grid-area: 1 / 1;
  display: grid;
  place-items: center;
  transition: transform 0.45s var(--ease);
  will-change: transform;
}

.orb-wrap {
  transform: translate3d(calc(var(--px, 0) * 18px), calc(var(--py, 0) * 14px), 0);
}

.card-wrap {
  transform: translate3d(calc(var(--px, 0) * -10px), calc(var(--py, 0) * -8px), 0);
}

.orb,
.orb-ring {
  grid-area: 1 / 1;
  border-radius: 50%;
}

.orb {
  width: clamp(300px, 32vw, 470px);
  aspect-ratio: 1;
  background: radial-gradient(circle at 50% 48%, var(--red-glow), rgba(229, 23, 23, 0.1) 42%, transparent 68%);
  animation: breathe 8s ease-in-out infinite alternate;
}

.orb-ring {
  width: clamp(340px, 36vw, 500px);
  aspect-ratio: 1;
  border: 1px solid rgba(229, 23, 23, 0.15);
  animation: ring-fade 8s ease-in-out infinite alternate;
}

@keyframes breathe {
  from { opacity: 0.72; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1.05); }
}

@keyframes ring-fade {
  from { opacity: 0.45; transform: scale(0.985); }
  to { opacity: 1; transform: scale(1.015); }
}

.hero-card {
  padding: clamp(18px, 2.4vw, 28px) clamp(22px, 2.8vw, 32px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.025);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-card);
  animation: float 7s ease-in-out infinite alternate;
}

.hero-card img {
  display: block;
  width: clamp(250px, 28vw, 380px);
  height: auto;
  aspect-ratio: 726 / 284;
  border-radius: 10px;
}

@keyframes float {
  from { transform: translateY(4px); }
  to { transform: translateY(-8px); }
}

/* ---- Entrance ---- */

.reveal {
  opacity: 0;
  transform: translateY(14px);
  animation: rise 0.9s var(--ease) forwards;
  animation-delay: calc(0.13s * var(--i, 0) + 0.08s);
}

@keyframes rise { to { opacity: 1; transform: none; } }

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

[data-reveal].in-view { opacity: 1; transform: none; }

/* ============ Sections ============ */

.section { padding: 44px 0 64px; }

.section-head { margin-bottom: 22px; }

.section-head h2 {
  margin: 0;
  color: var(--ink);
  font-size: 27px;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.work-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.work-row {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 24px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
  transition-delay: 0.1s;
}

.work-name {
  margin: 0;
  color: var(--ink-dim);
  font-size: 16.5px;
  font-weight: 500;
  letter-spacing: -0.005em;
}

.work-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.work-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--ink-dim);
  font-size: 14px;
  font-weight: 620;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--t-fast) ease;
}

.work-link:hover { color: var(--red-bright); }

/* ============ Contact ============ */

.contact-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 48px;
}

.contact-label {
  margin: 0 0 10px;
  color: var(--muted);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.contact-mail {
  display: inline-block;
  color: var(--ink);
  font-size: clamp(21px, 3vw, 31px);
  font-weight: 650;
  letter-spacing: -0.01em;
  text-decoration: none;
  word-break: break-all;
  transition: color var(--t-fast) ease;
}

.contact-mail:hover { color: var(--red-bright); }

.contact-qr {
  margin: 0;
  display: grid;
  place-items: center;
  gap: 12px;
}

.contact-qr img {
  display: block;
  width: 126px;
  height: auto;
  padding: 10px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.35);
}

.contact-qr figcaption {
  color: var(--muted);
  font-size: 12.5px;
  letter-spacing: 0.02em;
}

/* ============ Footer ============ */

.site-footer {
  border-top: 1px solid var(--line);
  background: rgba(13, 13, 16, 0.6);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 0;
  color: var(--muted);
  font-size: 13px;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  color: var(--muted);
}

.footer-brand img { display: block; border-radius: 50%; }

.footer-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px 20px;
}

.footer-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--muted);
  text-decoration: none;
  transition: color var(--t-fast) ease;
}

.footer-link:hover { color: var(--ink); }

/* ============ Responsive ============ */

@media (max-width: 880px) {
  .hero {
    grid-template-columns: 1fr;
    padding: 48px 0 36px;
  }

  .hero h1 { max-width: none; }

  .hero-visual {
    min-height: 340px;
    margin-top: 12px;
  }

  .orb { width: 320px; }
  .orb-ring { width: 360px; }

  .hero-card img { width: min(300px, 72vw); }

  .section { padding: 40px 0 56px; }

  .contact-grid {
    grid-template-columns: 1fr;
    align-items: start;
    gap: 36px;
  }
}

@media (max-width: 480px) {
  .shell { width: calc(100% - 36px); }

  .brand-name { font-size: 16px; }

  .header-nav .btn-sm { display: none; }

  .hero h1 { font-size: clamp(38px, 11vw, 46px); }

  .contact-mail { font-size: clamp(17px, 5.2vw, 22px); }

  .contact-qr { justify-items: start; }

  .hero-card { padding: 16px 18px; }

  .work-row {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
}

/* ============ Reduced motion ============ */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  .ambient, .orb, .orb-ring, .hero-card, .status-pill .dot, .status-pill .dot::after {
    animation: none;
  }

  .reveal, [data-reveal] {
    opacity: 1;
    transform: none;
    animation: none;
    transition: none;
  }

  .orb-wrap, .card-wrap { transform: none; transition: none; }

  .lang-toggle .knob { transition: none; }

  .menu-panel, .menu-caret, .btn { transition: none; }
}