/* 极光互娱 AI · 官网首页 */
:root {
  --bg-dark: #050810;
  --bg-dark-2: #0c1222;
  --aurora-cyan: #22d3ee;
  --aurora-purple: #a78bfa;
  --aurora-orange: #ff6b35;
  --aurora-pink: #f472b6;
  --text-light: #e8edf5;
  --text-muted: #94a3b8;
  --bg-light: #faf8f5;
  --bg-paper: #fffef9;
  --text-dark: #1a1a2e;
  --sketch-line: #2d2d2d;
  --radius: 16px;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg-dark);
  color: var(--text-light);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ── Scroll progress & theme transition ── */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--aurora-cyan), var(--aurora-orange));
  z-index: 9999;
  transition: width 0.1s linear;
}

body.theme-light {
  background: var(--bg-light);
  color: var(--text-dark);
}

/* ── Nav ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  transition: background 0.4s var(--ease-out-expo), backdrop-filter 0.4s, box-shadow 0.4s;
}

.nav.scrolled {
  background: rgba(5, 8, 16, 0.85);
  backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06);
}

.nav.scrolled.light {
  background: rgba(250, 248, 245, 0.9);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.06);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  color: inherit;
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
}

.nav-logo img {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  object-fit: cover;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.3s;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--aurora-orange);
  transition: width 0.3s var(--ease-out-expo);
}

.nav-links a:hover {
  color: var(--text-light);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav.scrolled.light .nav-links a {
  color: #64748b;
}

.nav.scrolled.light .nav-links a:hover {
  color: var(--text-dark);
}

.nav-cta {
  padding: 0.5rem 1.2rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--aurora-orange), #ff8c5a);
  color: #fff !important;
  font-weight: 600;
  font-size: 0.85rem;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.3s var(--ease-out-expo), box-shadow 0.3s;
  box-shadow: 0 0 20px rgba(255, 107, 53, 0.35);
}

.nav-cta:hover {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 0 32px rgba(255, 107, 53, 0.5);
}

.nav-cta::after {
  display: none !important;
}

/* ── Hero ── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

#particle-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}

.aurora {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  overflow: hidden;
}

.aurora-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.45;
  animation: aurora-drift 12s ease-in-out infinite alternate;
}

.aurora-blob:nth-child(1) {
  width: 60vw;
  height: 60vw;
  top: -20%;
  left: -10%;
  background: radial-gradient(circle, var(--aurora-cyan) 0%, transparent 70%);
  animation-delay: 0s;
}

.aurora-blob:nth-child(2) {
  width: 50vw;
  height: 50vw;
  top: 10%;
  right: -15%;
  background: radial-gradient(circle, var(--aurora-purple) 0%, transparent 70%);
  animation-delay: -4s;
}

.aurora-blob:nth-child(3) {
  width: 40vw;
  height: 40vw;
  bottom: -10%;
  left: 30%;
  background: radial-gradient(circle, var(--aurora-orange) 0%, transparent 70%);
  animation-delay: -8s;
  opacity: 0.3;
}

@keyframes aurora-drift {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(40px, -30px) scale(1.08); }
}

.hero-grid {
  position: absolute;
  inset: 0;
  z-index: 2;
  background-image:
    linear-gradient(rgba(34, 211, 238, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(34, 211, 238, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 50%, black 20%, transparent 80%);
}

.hero-content {
  position: relative;
  z-index: 10;
  text-align: center;
  padding: 2rem;
  max-width: 900px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  border-radius: 999px;
  border: 1px solid rgba(34, 211, 238, 0.3);
  background: rgba(34, 211, 238, 0.08);
  font-size: 0.8rem;
  color: var(--aurora-cyan);
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fade-up 0.8s var(--ease-out-expo) 0.2s forwards;
}

.hero-badge .pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--aurora-cyan);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.4); }
}

.hero-title {
  font-size: clamp(2.8rem, 8vw, 5.5rem);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  opacity: 0;
  animation: fade-up 0.8s var(--ease-out-expo) 0.4s forwards;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #fff 0%, var(--aurora-cyan) 40%, var(--aurora-orange) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1rem, 2.5vw, 1.35rem);
  color: var(--text-muted);
  line-height: 1.7;
  max-width: 600px;
  margin: 0 auto 2.5rem;
  opacity: 0;
  animation: fade-up 0.8s var(--ease-out-expo) 0.6s forwards;
}

.hero-subtitle em {
  color: var(--aurora-orange);
  font-style: normal;
  font-weight: 600;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  opacity: 0;
  animation: fade-up 0.8s var(--ease-out-expo) 0.8s forwards;
}

.btn-primary {
  position: relative;
  padding: 0.9rem 2rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--aurora-orange), #ff8c5a);
  color: #fff;
  font-weight: 700;
  font-size: 1rem;
  border: none;
  cursor: pointer;
  text-decoration: none;
  overflow: hidden;
  transition: transform 0.3s var(--ease-out-expo), box-shadow 0.3s;
  box-shadow: 0 4px 24px rgba(255, 107, 53, 0.4);
}

.btn-primary::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  transition: left 0.5s;
}

.btn-primary:hover::before {
  left: 100%;
}

.btn-primary:hover {
  transform: translateY(-3px) scale(1.04);
  box-shadow: 0 8px 40px rgba(255, 107, 53, 0.55);
}

.btn-ghost {
  padding: 0.9rem 2rem;
  border-radius: 999px;
  background: transparent;
  color: var(--text-light);
  font-weight: 600;
  font-size: 1rem;
  border: 1px solid rgba(255, 255, 255, 0.2);
  cursor: pointer;
  text-decoration: none;
  transition: border-color 0.3s, background 0.3s, transform 0.3s var(--ease-out-expo);
}

.btn-ghost:hover {
  border-color: var(--aurora-cyan);
  background: rgba(34, 211, 238, 0.08);
  transform: translateY(-3px);
}

.hero-mascot {
  position: absolute;
  right: 8%;
  bottom: 15%;
  width: clamp(120px, 18vw, 220px);
  z-index: 10;
  opacity: 0;
  animation: mascot-enter 1.2s var(--ease-out-expo) 1s forwards, mascot-float 4s ease-in-out 2.2s infinite;
  filter: drop-shadow(0 0 30px rgba(255, 107, 53, 0.3));
  pointer-events: none;
}

@keyframes mascot-enter {
  from { opacity: 0; transform: translateY(40px) rotate(-5deg); }
  to { opacity: 1; transform: translateY(0) rotate(0); }
}

@keyframes mascot-float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.scroll-hint {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-muted);
  font-size: 0.75rem;
  opacity: 0;
  animation: fade-up 0.8s var(--ease-out-expo) 1.2s forwards;
}

.scroll-hint .mouse {
  width: 24px;
  height: 38px;
  border: 2px solid rgba(255,255,255,0.3);
  border-radius: 12px;
  position: relative;
}

.scroll-hint .mouse::after {
  content: "";
  position: absolute;
  top: 6px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  background: var(--aurora-cyan);
  border-radius: 2px;
  animation: scroll-wheel 2s ease-in-out infinite;
}

@keyframes scroll-wheel {
  0% { opacity: 1; transform: translateX(-50%) translateY(0); }
  100% { opacity: 0; transform: translateX(-50%) translateY(12px); }
}

@keyframes fade-up {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Transition divider ── */
.theme-divider {
  position: relative;
  height: 120px;
  background: linear-gradient(180deg, var(--bg-dark) 0%, var(--bg-light) 100%);
  z-index: 5;
}

.theme-divider::before {
  content: "";
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='100' height='20' viewBox='0 0 100 20' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M0 10 Q25 0 50 10 T100 10' fill='none' stroke='%23ff6b35' stroke-width='2' opacity='0.3'/%3E%3C/svg%3E") repeat-x center;
  background-size: 100px 20px;
}

/* ── Light sections ── */
.light-section {
  background: var(--bg-light);
  color: var(--text-dark);
  position: relative;
}

.light-section::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
  opacity: 0.5;
}

.section {
  padding: 6rem 2rem;
  max-width: 1100px;
  margin: 0 auto;
  position: relative;
}

.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--aurora-orange);
  margin-bottom: 0.75rem;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out-expo), transform 0.6s var(--ease-out-expo);
}

.section-label.visible {
  opacity: 1;
  transform: translateY(0);
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out-expo) 0.1s, transform 0.6s var(--ease-out-expo) 0.1s;
}

.section-title.visible {
  opacity: 1;
  transform: translateY(0);
}

.section-desc {
  font-size: 1.05rem;
  color: #64748b;
  line-height: 1.8;
  max-width: 560px;
  margin-bottom: 3rem;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out-expo) 0.2s, transform 0.6s var(--ease-out-expo) 0.2s;
}

.section-desc.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Sketch cards */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.sketch-card {
  background: var(--bg-paper);
  border: 2px solid var(--sketch-line);
  border-radius: var(--radius);
  padding: 2rem;
  position: relative;
  transition: transform 0.4s var(--ease-out-expo), box-shadow 0.4s;
  opacity: 0;
  transform: translateY(40px) rotate(var(--rotate, 0deg));
}

.sketch-card.visible {
  opacity: 1;
  transform: translateY(0) rotate(var(--rotate, 0deg));
}

.sketch-card:nth-child(1) { --rotate: -0.8deg; transition-delay: 0.1s; }
.sketch-card:nth-child(2) { --rotate: 0.5deg; transition-delay: 0.2s; }
.sketch-card:nth-child(3) { --rotate: -0.3deg; transition-delay: 0.3s; }

.sketch-card::before {
  content: "";
  position: absolute;
  top: -3px;
  left: -3px;
  right: -3px;
  bottom: -3px;
  border: 2px dashed rgba(255, 107, 53, 0.25);
  border-radius: calc(var(--radius) + 4px);
  pointer-events: none;
}

.sketch-card:hover {
  transform: translateY(-8px) rotate(0deg) !important;
  box-shadow: 8px 12px 0 rgba(255, 107, 53, 0.15);
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1rem;
  background: rgba(255, 107, 53, 0.1);
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.card-ratio {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--aurora-orange);
  background: rgba(255, 107, 53, 0.1);
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  margin-bottom: 0.75rem;
}

.card-text {
  font-size: 0.95rem;
  color: #64748b;
  line-height: 1.7;
}

/* Tags */
.tags-section {
  text-align: center;
}

.tags-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-top: 2rem;
}

.tag-chip {
  padding: 0.6rem 1.2rem;
  border: 2px solid var(--sketch-line);
  border-radius: 999px;
  background: var(--bg-paper);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: default;
  transition: all 0.3s var(--ease-out-expo);
  opacity: 0;
  transform: scale(0.8);
}

.tag-chip.visible {
  opacity: 1;
  transform: scale(1);
}

.tag-chip:hover {
  background: var(--aurora-orange);
  color: #fff;
  border-color: var(--aurora-orange);
  transform: scale(1.08) rotate(-2deg);
  box-shadow: 4px 4px 0 var(--sketch-line);
}

/* About */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.about-mascot-wrap {
  position: relative;
  display: flex;
  justify-content: center;
}

.about-mascot-wrap img {
  width: min(320px, 80%);
  filter: drop-shadow(4px 8px 0 rgba(255, 107, 53, 0.2));
  transition: transform 0.5s var(--ease-out-expo);
}

.about-mascot-wrap:hover img {
  transform: rotate(-3deg) scale(1.05);
}

.about-mascot-wrap::after {
  content: "极光星兔";
  position: absolute;
  bottom: -1rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--aurora-orange);
  background: var(--bg-paper);
  border: 2px solid var(--sketch-line);
  padding: 0.3rem 1rem;
  border-radius: 999px;
  transform: rotate(-2deg);
}

.about-text p {
  font-size: 1.05rem;
  line-height: 1.9;
  color: #475569;
  margin-bottom: 1rem;
}

.about-text p strong {
  color: var(--text-dark);
}

.about-values {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.5rem;
}

.value-pill {
  padding: 0.35rem 0.9rem;
  background: rgba(255, 107, 53, 0.08);
  border: 1px dashed var(--aurora-orange);
  border-radius: 999px;
  font-size: 0.8rem;
  color: var(--aurora-orange);
  font-weight: 600;
}

/* WeChat CTA */
.wechat-section {
  background: linear-gradient(135deg, #1a1a2e 0%, #0f172a 100%);
  color: var(--text-light);
  border-radius: 24px;
  margin: 0 2rem 6rem;
  max-width: 1060px;
  margin-left: auto;
  margin-right: auto;
  padding: 4rem 3rem;
  position: relative;
  overflow: hidden;
}

.wechat-section::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255, 107, 53, 0.2) 0%, transparent 70%);
  border-radius: 50%;
}

.wechat-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 3rem;
  align-items: center;
  position: relative;
  z-index: 1;
}

.wechat-title {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 800;
  margin-bottom: 0.75rem;
}

.wechat-title span {
  color: var(--aurora-orange);
}

.wechat-desc {
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 1.5rem;
}

.wechat-search {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.8rem 1.5rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 12px;
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.wechat-search .wx-icon {
  width: 28px;
  height: 28px;
  background: #07c160;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  color: #fff;
  font-weight: 900;
}

.wechat-qr-placeholder {
  width: 180px;
  background: #fff;
  border-radius: 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  transition: transform 0.4s var(--ease-out-expo);
}

.wechat-qr-placeholder:hover {
  transform: scale(1.05);
}

.wechat-qr-placeholder img {
  width: 148px;
  height: 148px;
  object-fit: contain;
  border-radius: 8px;
}

.wechat-qr-placeholder span {
  font-size: 0.7rem;
  color: #64748b;
  text-align: center;
}

/* Stats ticker */
.stats-bar {
  display: flex;
  justify-content: center;
  gap: 3rem;
  padding: 3rem 2rem;
  flex-wrap: wrap;
}

.stat-item {
  text-align: center;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out-expo), transform 0.6s var(--ease-out-expo);
}

.stat-item.visible {
  opacity: 1;
  transform: translateY(0);
}

.stat-num {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--aurora-orange);
  line-height: 1;
}

.stat-label {
  font-size: 0.85rem;
  color: #64748b;
  margin-top: 0.3rem;
}

/* Footer */
.footer {
  background: var(--bg-light);
  border-top: 2px dashed rgba(0,0,0,0.08);
  padding: 2rem;
  text-align: center;
  color: #94a3b8;
  font-size: 0.85rem;
}

.footer a {
  color: var(--aurora-orange);
  text-decoration: none;
}

/* Magnetic cursor glow on hero */
.cursor-glow {
  position: fixed;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(34, 211, 238, 0.08) 0%, transparent 70%);
  pointer-events: none;
  z-index: 3;
  transform: translate(-50%, -50%);
  transition: opacity 0.3s;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .hero-mascot { right: 5%; bottom: 8%; width: 100px; opacity: 0.6; }
  .about-grid { grid-template-columns: 1fr; gap: 2rem; }
  .wechat-inner { grid-template-columns: 1fr; text-align: center; }
  .wechat-qr-placeholder { margin: 0 auto; }
  .wechat-search { justify-content: center; }
  .stats-bar { gap: 2rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}