:root {
  --bg: #050508;
  --bg-elevated: #0c0c12;
  --bg-card: rgba(18, 18, 28, 0.72);
  --border: rgba(255, 255, 255, 0.08);
  --text: #f1f5f9;
  --text-muted: #94a3b8;
  --primary: #7c3aed;
  --primary-light: #a78bfa;
  --accent: #6366f1;
  --gradient: linear-gradient(135deg, #7c3aed 0%, #6366f1 50%, #3b82f6 100%);
  --header-h: 72px;
  --radius: 16px;
  --font: 'Noto Sans SC', system-ui, -apple-system, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
}

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

a {
  color: var(--primary-light);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: #fff;
}

.container {
  width: min(1120px, 92vw);
  margin: 0 auto;
}

/* Background */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(124, 58, 237, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124, 58, 237, 0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
  z-index: 0;
}

.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
  pointer-events: none;
  z-index: 0;
}

.bg-glow--1 {
  width: 520px;
  height: 520px;
  top: -120px;
  right: -80px;
  background: #7c3aed;
}

.bg-glow--2 {
  width: 400px;
  height: 400px;
  bottom: 10%;
  left: -100px;
  background: #2563eb;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-h);
  z-index: 100;
  background: rgba(5, 5, 8, 0.82);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  width: min(1120px, 92vw);
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 700;
  font-size: 1.1rem;
  flex-shrink: 0;
}

.logo-icon {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  background: var(--gradient);
  border-radius: 10px;
  font-size: 14px;
  color: #fff;
}

.nav {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1;
  justify-content: center;
}

.nav-link {
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 8px 14px;
  border-radius: 8px;
  transition: color 0.2s, background 0.2s;
}

.nav-link:hover,
.nav-link.is-active {
  color: var(--text);
  background: rgba(124, 58, 237, 0.15);
}

.header-cta {
  flex-shrink: 0;
}

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

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
}

/* Sections — full viewport */
.section {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--header-h) + 48px) 0 64px;
}

.section--dark {
  background: linear-gradient(180deg, transparent, rgba(12, 12, 18, 0.6) 20%, rgba(12, 12, 18, 0.6) 80%, transparent);
}

.section--hero {
  text-align: center;
}

.section--contact {
  min-height: auto;
  padding-bottom: 48px;
}

/* Typography */
.eyebrow {
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--primary-light);
  margin-bottom: 16px;
}

.hero-title {
  font-size: clamp(2.2rem, 6vw, 3.75rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
  background: linear-gradient(180deg, #fff 0%, #c4b5fd 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: clamp(1rem, 2.2vw, 1.15rem);
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 36px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  margin-bottom: 56px;
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 800px;
  margin: 0 auto 32px;
}

.stat {
  padding: 20px 12px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-card);
}

.stat-num {
  display: block;
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--primary-light);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.hero-mail {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  width: 28px;
  height: 44px;
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 14px;
}

.scroll-hint span {
  position: absolute;
  top: 8px;
  left: 50%;
  width: 4px;
  height: 8px;
  margin-left: -2px;
  background: var(--primary-light);
  border-radius: 2px;
  animation: scroll-bounce 2s infinite;
}

@keyframes scroll-bounce {
  0%, 100% { transform: translateY(0); opacity: 1; }
  50% { transform: translateY(10px); opacity: 0.3; }
}

.section-head {
  margin-bottom: 48px;
}

.section-head--center {
  text-align: center;
}

.section-head--center .section-desc {
  margin-left: auto;
  margin-right: auto;
}

.section-tag {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--primary-light);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 12px;
}

.section-lead {
  font-size: 1.1rem;
  color: var(--text-muted);
}

.section-desc {
  max-width: 640px;
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* Glass cards */
.glass {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  backdrop-filter: blur(12px);
}

/* About */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 24px;
  align-items: start;
}

.about-main {
  padding: 32px;
}

.about-main p + p {
  margin-top: 16px;
  color: var(--text-muted);
}

.about-cards {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mini-card {
  padding: 24px;
}

.mini-card-icon {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.mini-card h3 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.mini-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Services */
.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.service-card {
  padding: 28px;
  display: flex;
  flex-direction: column;
  transition: transform 0.25s, border-color 0.25s;
}

.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(124, 58, 237, 0.35);
}

.service-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-size: 1.4rem;
  margin-bottom: 16px;
}

.service-icon--purple { background: rgba(124, 58, 237, 0.2); }
.service-icon--blue { background: rgba(99, 102, 241, 0.2); }
.service-icon--cyan { background: rgba(34, 211, 238, 0.15); }
.service-icon--green { background: rgba(34, 197, 94, 0.15); }
.service-icon--orange { background: rgba(249, 115, 22, 0.15); }
.service-icon--pink { background: rgba(236, 72, 153, 0.15); }

.service-card h3 {
  font-size: 1.1rem;
  margin-bottom: 12px;
}

.service-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  flex: 1;
  margin-bottom: 16px;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tags span {
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(124, 58, 237, 0.12);
  color: var(--primary-light);
  border: 1px solid rgba(124, 58, 237, 0.2);
}

/* Tech */
.tech-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 24px;
  align-items: start;
}

.tech-stack {
  padding: 28px;
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

.tech-stack h3 {
  margin-bottom: 20px;
  font-size: 1.1rem;
}

.stack-list {
  list-style: none;
}

.stack-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  color: var(--text-muted);
}

.stack-list li:last-child {
  border-bottom: none;
}

.stack-list strong {
  display: block;
  color: var(--text);
  margin-bottom: 4px;
}

.tech-cards {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.tech-card {
  padding: 28px 28px 28px 80px;
  position: relative;
}

.tech-card-num {
  position: absolute;
  left: 24px;
  top: 28px;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  opacity: 0.5;
}

.tech-card h3 {
  margin-bottom: 8px;
}

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

/* Process */
.process-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.process-step {
  padding: 32px 24px;
  text-align: center;
}

.process-badge {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  border-radius: 50%;
  background: var(--gradient);
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 1.1rem;
}

.process-step h3 {
  margin-bottom: 12px;
}

.process-step p {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* Contact */
.contact-wrap {
  max-width: 960px;
  margin: 0 auto;
}

.contact-layout {
  display: grid;
  grid-template-columns: minmax(260px, 320px) 1fr;
  gap: 24px;
  align-items: start;
}

.wechat-card {
  padding: 28px;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.wechat-card-head {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  margin-bottom: 20px;
}

.wechat-card-head h3 {
  font-size: 1.15rem;
  margin-bottom: 6px;
}

.wechat-card-head p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.wechat-ico--lg {
  font-size: 2rem;
  line-height: 1;
}

.wechat-id-panel {
  margin-bottom: 16px;
}

.wechat-id-label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.wechat-id-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 18px;
  border-radius: 12px;
  border: 1px solid rgba(124, 58, 237, 0.45);
  background: rgba(124, 58, 237, 0.12);
  color: var(--text);
  font-family: inherit;
  font-size: 1rem;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s, transform 0.15s;
}

.wechat-id-btn:hover {
  border-color: var(--primary-light);
  background: rgba(124, 58, 237, 0.22);
  transform: translateY(-1px);
}

.wechat-id-btn--block {
  width: 100%;
  justify-content: space-between;
}

.wechat-id-btn strong {
  font-weight: 600;
  letter-spacing: 0.02em;
}

.copy-tag {
  font-size: 0.75rem;
  padding: 3px 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: var(--primary-light);
}

.wechat-qr-wrap {
  text-align: center;
  margin: 16px 0;
  padding: 16px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px dashed var(--border);
}

.wechat-qr-wrap img {
  display: block;
  margin: 0 auto 10px;
  border-radius: 10px;
}

.wechat-qr-wrap p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.wechat-tip {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.hero-contact {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 16px;
  margin: 28px 0 8px;
  padding: 16px 20px;
  max-width: 520px;
}

.hero-contact-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-contact-hint {
  width: 100%;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.contact-form-title {
  font-size: 1rem;
  margin: 0 0 20px;
  color: var(--text-muted);
  font-weight: 500;
}

.footer-wechat {
  background: none;
  border: none;
  padding: 0;
  color: var(--primary-light);
  font: inherit;
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.footer-wechat:hover {
  color: #fff;
}

.contact-form {
  padding: 36px;
}

.form-row {
  margin-bottom: 20px;
}

.form-row label {
  display: block;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.form-row input,
.form-row textarea {
  width: 100%;
  padding: 14px 16px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: rgba(0, 0, 0, 0.35);
  color: var(--text);
  font-family: inherit;
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

.form-row input:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--primary);
}

.form-row textarea {
  resize: vertical;
  min-height: 100px;
}

.form-tip {
  margin-top: 16px;
  font-size: 0.85rem;
  color: var(--primary-light);
  text-align: center;
  min-height: 1.2em;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  font-family: inherit;
}

.btn--sm {
  padding: 10px 20px;
  font-size: 0.85rem;
}

.btn--lg {
  padding: 16px 36px;
  font-size: 1rem;
}

.btn--block {
  width: 100%;
}

.btn--primary {
  background: var(--gradient);
  color: #fff;
  box-shadow: 0 8px 32px rgba(124, 58, 237, 0.35);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 40px rgba(124, 58, 237, 0.45);
  color: #fff;
}

.btn--ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}

.btn--ghost:hover {
  border-color: var(--primary-light);
  color: #fff;
}

/* Footer */
.site-footer {
  position: relative;
  z-index: 1;
  padding: 32px 0;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-inner p + p {
  margin-top: 8px;
}

.footer-beian {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 0.78rem;
  line-height: 1.75;
  color: #64748b;
}

.footer-beian a {
  color: #94a3b8;
}

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

.link {
  color: var(--primary-light);
}

/* Responsive */
@media (max-width: 1024px) {
  .service-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .tech-layout {
    grid-template-columns: 1fr;
  }
  .tech-stack {
    position: static;
  }
  .process-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .contact-layout {
    grid-template-columns: 1fr;
  }
  .wechat-card {
    position: static;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(5, 5, 8, 0.98);
    padding: 24px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.3s, opacity 0.3s;
  }
  .nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .header-cta {
    display: none;
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .service-grid {
    grid-template-columns: 1fr;
  }
  .process-grid {
    grid-template-columns: 1fr;
  }
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  .hero-actions .btn {
    width: 100%;
    justify-content: center;
  }
}