/* ============================================================
   欢迎网站样式表 —— 设计系统: Sky Blue + Warm Orange
   配色: Primary #0EA5E9 | Secondary #38BDF8 | CTA #F97316
   字体: Quicksand（正文）+ Caveat（装饰）
   ============================================================ */

:root {
  --primary: #0ea5e9;
  --primary-dark: #0369a1;
  --primary-light: #38bdf8;
  --cta: #f97316;
  --cta-dark: #ea580c;
  --bg: #f0f9ff;
  --surface: #ffffff;
  --text: #0c4a6e;
  --text-muted: #5a86a0;
  --border: rgba(14, 165, 233, 0.16);
  --shadow-sm: 0 2px 10px rgba(12, 74, 110, 0.06);
  --shadow-md: 0 10px 30px rgba(12, 74, 110, 0.10);
  --shadow-lg: 0 24px 60px rgba(12, 74, 110, 0.16);
  --radius: 16px;
  --radius-lg: 24px;
  --font-body: "Quicksand", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-hand: "Caveat", cursive;
  --nav-height: 72px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

body {
  font-family: var(--font-body);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

ul {
  list-style: none;
}

.container {
  width: min(1120px, 92%);
  margin-inline: auto;
}

::selection {
  background: var(--primary);
  color: #fff;
}

/* 无障碍焦点样式 */
:focus-visible {
  outline: 3px solid rgba(14, 165, 233, 0.55);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 滚动显示动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition:
    opacity 0.8s var(--ease),
    transform 0.8s var(--ease);
  transition-delay: var(--reveal-delay, 0s);
  will-change: opacity, transform;
}

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

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.9rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 1rem;
  line-height: 1;
  transition:
    transform 0.25s var(--ease),
    box-shadow 0.25s var(--ease),
    background 0.25s var(--ease),
    color 0.25s var(--ease);
  cursor: pointer;
}

.btn svg {
  width: 18px;
  height: 18px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--cta), var(--cta-dark));
  color: #fff;
  box-shadow: 0 10px 24px rgba(249, 115, 22, 0.35);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 32px rgba(249, 115, 22, 0.45);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.75);
  color: var(--text);
  border: 1.5px solid var(--border);
  backdrop-filter: blur(8px);
}

.btn-ghost:hover {
  background: #fff;
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.btn-light {
  background: rgba(255, 255, 255, 0.18);
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(8px);
}

.btn-light:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: translateY(-3px);
}

.btn-sm {
  padding: 0.6rem 1.4rem;
  font-size: 0.9rem;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--nav-height);
  z-index: 100;
  transition:
    background 0.35s ease,
    box-shadow 0.35s ease;
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text);
}

.logo-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 12px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  box-shadow: 0 6px 16px rgba(14, 165, 233, 0.35);
  transition: transform 0.3s var(--ease);
}

.logo:hover .logo-mark {
  transform: rotate(-8deg) scale(1.06);
}

.logo-mark svg {
  width: 20px;
  height: 20px;
}

.logo-accent {
  color: var(--primary);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.main-nav a {
  position: relative;
  font-weight: 500;
  color: var(--text-muted);
  padding: 0.3rem 0;
  transition: color 0.25s ease;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 2.5px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}

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

.main-nav a:hover::after,
.main-nav a.active::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2.5px;
  border-radius: 2px;
  background: var(--text);
  transition: transform 0.3s var(--ease), opacity 0.3s ease;
}

.nav-toggle.open span:nth-child(1) {
  transform: translateY(7.5px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7.5px) rotate(-45deg);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100svh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: calc(var(--nav-height) + 3rem) 0 4rem;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    radial-gradient(60% 55% at 18% 12%, rgba(14, 165, 233, 0.16), transparent 65%),
    radial-gradient(50% 45% at 85% 20%, rgba(56, 189, 248, 0.18), transparent 60%),
    radial-gradient(55% 55% at 70% 85%, rgba(249, 115, 22, 0.10), transparent 65%);
}

.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.55;
  animation: float 12s ease-in-out infinite;
}

.blob-1 {
  width: 380px;
  height: 380px;
  background: rgba(14, 165, 233, 0.22);
  top: -120px;
  left: -100px;
}

.blob-2 {
  width: 300px;
  height: 300px;
  background: rgba(56, 189, 248, 0.22);
  top: 30%;
  right: -120px;
  animation-delay: -4s;
}

.blob-3 {
  width: 260px;
  height: 260px;
  background: rgba(249, 115, 22, 0.16);
  bottom: -80px;
  left: 30%;
  animation-delay: -8s;
}

.grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(14, 165, 233, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(14, 165, 233, 0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(75% 65% at 50% 40%, #000 30%, transparent 100%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.4rem;
}

.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 1.1rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--border);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--primary-dark);
  backdrop-filter: blur(8px);
}

.dot-pulse {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #22c55e;
  position: relative;
}

.dot-pulse::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  border: 2px solid #22c55e;
  animation: pulse 1.8s ease-out infinite;
}

.hero-title {
  font-size: clamp(2.6rem, 7vw, 4.6rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.01em;
  max-width: 16em;
}

.gradient-text {
  background: linear-gradient(100deg, var(--primary) 10%, var(--primary-light) 45%, var(--cta) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-subtitle {
  max-width: 560px;
  font-size: clamp(1rem, 2.4vw, 1.18rem);
  color: var(--text-muted);
  font-weight: 500;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-top: 0.6rem;
}

.scroll-hint {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  margin-top: 2.5rem;
  color: var(--text-muted);
}

.mouse {
  width: 26px;
  height: 42px;
  border: 2px solid var(--text-muted);
  border-radius: 14px;
  display: flex;
  justify-content: center;
  padding-top: 7px;
}

.wheel {
  width: 4px;
  height: 8px;
  border-radius: 3px;
  background: var(--primary);
  animation: wheel 1.8s var(--ease) infinite;
}

.scroll-text {
  font-size: 0.8rem;
  letter-spacing: 0.15em;
}

/* ---------- 通用 Section ---------- */
.section {
  padding: 6.5rem 0;
  position: relative;
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 3.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  align-items: center;
}

.section-eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cta);
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.25;
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.02rem;
}

/* ---------- 特色 ---------- */
.features {
  background: var(--surface);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.6rem;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 1.6rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  transition:
    transform 0.35s var(--ease),
    box-shadow 0.35s var(--ease),
    border-color 0.35s ease;
}

.feature-card:nth-child(2) {
  --reveal-delay: 0.1s;
}

.feature-card:nth-child(3) {
  --reveal-delay: 0.2s;
}

.feature-card:nth-child(4) {
  --reveal-delay: 0.3s;
}

.feature-card:hover {
  transform: translateY(-8px);
  border-color: rgba(14, 165, 233, 0.4);
  box-shadow: var(--shadow-lg);
  background: #fff;
}

.feature-icon {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border-radius: 16px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  box-shadow: 0 10px 20px rgba(14, 165, 233, 0.28);
  margin-bottom: 0.4rem;
}

.feature-icon svg {
  width: 26px;
  height: 26px;
}

.feature-card:nth-child(odd) .feature-icon {
  background: linear-gradient(135deg, var(--cta), #fb923c);
  box-shadow: 0 10px 20px rgba(249, 115, 22, 0.28);
}

.feature-card h3 {
  font-size: 1.18rem;
  font-weight: 700;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.94rem;
  flex: 1;
}

/* ---------- 统计 ---------- */
.stats {
  background:
    linear-gradient(rgba(255, 255, 255, 0.92), rgba(255, 255, 255, 0.92)),
    radial-gradient(50% 60% at 50% 40%, var(--primary-light), transparent 70%);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.6rem;
}

.stat-item {
  text-align: center;
  padding: 2.2rem 1rem;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--border);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.stat-item:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}

.stat-value {
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  font-weight: 700;
  line-height: 1;
  background: linear-gradient(135deg, var(--primary), var(--cta));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.stat-label {
  margin-top: 0.7rem;
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
}

/* ---------- 最新动态 ---------- */
.updates-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
}

.update-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 1.8rem;
  overflow: hidden;
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.update-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light), var(--cta));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s var(--ease);
}

.update-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.update-card:hover::before {
  transform: scaleX(1);
}

.update-card:nth-child(2) {
  --reveal-delay: 0.12s;
}

.update-card:nth-child(3) {
  --reveal-delay: 0.24s;
}

.update-date {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--primary-dark);
  background: rgba(14, 165, 233, 0.1);
  display: inline-block;
  align-self: flex-start;
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
}

.update-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.4;
}

.update-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  flex: 1;
}

.update-link {
  font-weight: 700;
  color: var(--cta);
  font-size: 0.95rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  transition: gap 0.25s var(--ease);
  cursor: pointer;
}

.update-link::after {
  content: "→";
  transition: transform 0.25s var(--ease);
}

.update-link:hover {
  gap: 0.55rem;
}

/* ---------- 关于 ---------- */
.about {
  background: var(--surface);
}

.about-inner {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 4rem;
  align-items: center;
}

.about-visual {
  position: relative;
  display: grid;
  place-items: center;
  padding: 2rem;
}

.avatar-ring {
  width: min(320px, 100%);
  aspect-ratio: 1;
  border-radius: 50%;
  padding: 12px;
  background: conic-gradient(
    from 180deg,
    var(--primary),
    var(--primary-light),
    var(--cta),
    var(--primary)
  );
  animation: spin-slow 16s linear infinite;
}

.avatar {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: #fff;
  display: grid;
  place-items: center;
  color: var(--primary);
}

.avatar svg {
  width: 58%;
  height: 58%;
}

.float-tag {
  position: absolute;
  font-family: var(--font-hand);
  font-size: 1.35rem;
  font-weight: 600;
  padding: 0.35rem 1rem;
  border-radius: 999px;
  background: #fff;
  box-shadow: var(--shadow-md);
  animation: float 5s ease-in-out infinite;
  color: var(--text);
}

.tag-1 {
  top: 8%;
  left: 6%;
  color: var(--primary-dark);
  animation-delay: -1s;
}

.tag-2 {
  bottom: 12%;
  left: 0;
  color: var(--cta-dark);
  animation-delay: -2.5s;
}

.tag-3 {
  bottom: 6%;
  right: 4%;
  color: var(--primary-dark);
  animation-delay: -4s;
}

.about-content {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.about-content .section-title {
  margin-bottom: 0.4rem;
}

.about-content p {
  color: var(--text-muted);
  font-size: 1.02rem;
}

.about-list {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  margin-top: 0.8rem;
}

.about-list li {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-weight: 600;
}

.about-list svg {
  width: 22px;
  height: 22px;
  flex-shrink: 0;
  color: #22c55e;
  padding: 3px;
  border-radius: 50%;
  background: rgba(34, 197, 94, 0.12);
}

/* ---------- CTA ---------- */
.cta-card {
  position: relative;
  overflow: hidden;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.1rem;
  padding: 4rem 2rem;
  border-radius: 32px;
  color: #fff;
  background: linear-gradient(135deg, #0369a1, #0ea5e9 55%, #38bdf8);
  box-shadow: 0 30px 70px rgba(3, 105, 161, 0.35);
}

.cta-card .section-title {
  color: #fff;
}

.cta-card p {
  max-width: 480px;
  font-weight: 500;
  opacity: 0.92;
}

.cta-card .hero-actions {
  margin-top: 0.8rem;
}

.cta-blob {
  position: absolute;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.12);
  filter: blur(30px);
}

.cta-blob-1 {
  width: 220px;
  height: 220px;
  top: -70px;
  right: -40px;
}

.cta-blob-2 {
  width: 180px;
  height: 180px;
  bottom: -60px;
  left: -30px;
  background: rgba(249, 115, 22, 0.3);
}

/* ---------- 页脚 ---------- */
.site-footer {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
  background: var(--surface);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.site-footer p {
  color: var(--text-muted);
  font-size: 0.92rem;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
}

.footer-links a {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.92rem;
  transition: color 0.25s ease;
  cursor: pointer;
}

.footer-links a:hover {
  color: var(--primary);
}

/* ---------- 动画关键帧 ---------- */
@keyframes float {
  0%,
  100% {
    transform: translateY(0) translateX(0);
  }
  50% {
    transform: translateY(-22px) translateX(12px);
  }
}

@keyframes spin-slow {
  to {
    transform: rotate(360deg);
  }
}

@keyframes pulse {
  0% {
    transform: scale(1);
    opacity: 0.8;
  }
  100% {
    transform: scale(1.9);
    opacity: 0;
  }
}

@keyframes wheel {
  0% {
    transform: translateY(0);
    opacity: 1;
  }
  70% {
    transform: translateY(10px);
    opacity: 0;
  }
  100% {
    transform: translateY(0);
    opacity: 0;
  }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .feature-grid,
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-inner {
    grid-template-columns: 1fr;
    gap: 2.5rem;
    text-align: center;
  }

  .about-visual {
    order: -1;
  }

  .about-list {
    align-items: flex-start;
    text-align: left;
    justify-content: center;
    margin-inline: auto;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 64px;
  }

  .section {
    padding: 4.5rem 0;
  }

  .header-cta {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .main-nav {
    position: fixed;
    top: var(--nav-height);
    right: 0;
    width: min(280px, 78vw);
    height: calc(100svh - var(--nav-height));
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 1.5rem 2rem;
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(14px);
    box-shadow: -12px 0 40px rgba(12, 74, 110, 0.12);
    transform: translateX(100%);
    transition: transform 0.4s var(--ease);
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .main-nav a {
    width: 100%;
    padding: 0.85rem 0;
    font-size: 1.05rem;
    border-bottom: 1px solid var(--border);
  }

  .main-nav a::after {
    display: none;
  }

  .updates-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: calc(var(--nav-height) + 2rem);
  }

  .scroll-hint {
    margin-top: 1.6rem;
  }
}

@media (max-width: 480px) {
  .feature-grid,
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
    width: 100%;
    max-width: 300px;
  }

  .hero-actions .btn {
    width: 100%;
  }

  .cta-card {
    padding: 3rem 1.4rem;
  }

  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

/* ---------- 减少动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}