/* ==========================================================================
   MIB 迈步科技 - Global Styles
   ========================================================================== */

:root {
  --primary: #3b2fbf;
  --primary-dark: #241a8a;
  --accent: #6d5cff;
  --accent-light: #9d8fff;
  --dark: #14112e;
  --text: #3c3a5a;
  --text-light: #6f6c93;
  --bg: #ffffff;
  --bg-soft: #f5f4fe;
  --border: #e5e2f5;
  --shadow-sm: 0 2px 10px rgba(59, 47, 191, 0.06);
  --shadow-md: 0 12px 32px rgba(59, 47, 191, 0.12);
  --radius: 14px;
  --container: 1180px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

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

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

ul {
  list-style: none;
}

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(20, 17, 46, 0.72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.site-header.scrolled {
  background: rgba(20, 17, 46, 0.92);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.2);
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

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

.logo-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-weight: 800;
  font-size: 15px;
  letter-spacing: 0.5px;
}

.logo-text {
  font-weight: 700;
  font-size: 17px;
  color: #fff;
  letter-spacing: 1px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 30px;
}

.nav-menu a {
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.82);
  transition: color 0.2s ease;
  position: relative;
  padding: 6px 0;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: #fff;
}

.nav-menu a.active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
}

.nav-menu .nav-cta {
  color: #fff;
  border: 1px solid rgba(157, 143, 255, 0.6);
  border-radius: 999px;
  padding: 8px 20px;
  transition: background 0.2s ease;
}

.nav-menu .nav-cta:hover {
  background: rgba(109, 92, 255, 0.25);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

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

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

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

.hero {
  position: relative;
  background: linear-gradient(135deg, #0d0a2e 0%, var(--primary-dark) 40%, var(--primary) 100%);
  overflow: hidden;
  min-height: 100vh;
  display: flex;
  align-items: center;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse at 30% 40%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at 30% 40%, #000 30%, transparent 75%);
}

.hero::after {
  content: '';
  position: absolute;
  top: -35%;
  right: -12%;
  width: 680px;
  height: 680px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(109, 92, 255, 0.4), transparent 70%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding: 148px 24px 110px;
  width: 100%;
}

.hero-tagline {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--accent-light);
  border: 1px solid rgba(157, 143, 255, 0.4);
  border-radius: 999px;
  padding: 7px 18px;
  margin-bottom: 26px;
  background: rgba(109, 92, 255, 0.1);
}

.hero h1 {
  font-size: clamp(38px, 6vw, 66px);
  font-weight: 900;
  line-height: 1.18;
  color: #fff;
  letter-spacing: 2px;
  margin-bottom: 24px;
}

.hero-sub {
  font-size: clamp(15px, 2vw, 18px);
  color: rgba(255, 255, 255, 0.82);
  max-width: 640px;
  margin-bottom: 38px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 64px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 30px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  color: #1a0f66;
  box-shadow: 0 8px 24px rgba(109, 92, 255, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(109, 92, 255, 0.5);
}

.btn-outline {
  border: 1.5px solid rgba(255, 255, 255, 0.5);
  color: #fff;
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.12);
  transform: translateY(-2px);
}

/* Hero stats */

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 48px;
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-num {
  font-size: clamp(32px, 4vw, 44px);
  font-weight: 800;
  color: #fff;
  line-height: 1.1;
}

.stat-suffix {
  font-size: 20px;
  font-weight: 700;
  color: var(--accent-light);
  margin-left: 4px;
}

.stat-label {
  font-size: 13.5px;
  color: rgba(255, 255, 255, 0.6);
  margin-top: 6px;
}

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

.section {
  padding: 96px 0;
}

.section-label {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-head {
  text-align: center;
  margin-bottom: 52px;
}

.section-head h2,
.about-text h2,
.join-info h2 {
  font-size: clamp(28px, 3.5vw, 40px);
  font-weight: 800;
  color: var(--dark);
  letter-spacing: -0.3px;
  line-height: 1.25;
}

.section-desc {
  margin-top: 14px;
  font-size: 16px;
  color: var(--text-light);
}

/* About */

.about {
  background: var(--bg);
}

.about-inner {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
}

.about-text p {
  margin: 18px 0;
  font-size: 16px;
}

.about-points {
  margin-top: 22px;
}

.about-points li {
  position: relative;
  padding-left: 28px;
  margin-bottom: 10px;
  font-size: 15.5px;
}

.about-points li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: radial-gradient(circle at center, var(--accent) 4px, transparent 5px);
  border: 2px solid var(--accent);
}

.about-image img {
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
}

/* Business */

.business {
  background: var(--bg-soft);
}

.biz-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 30px;
}

.biz-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  position: relative;
  overflow: hidden;
}

.biz-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  opacity: 0.7;
}

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

.biz-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  background: linear-gradient(135deg, rgba(59, 47, 191, 0.08), rgba(109, 92, 255, 0.16));
  margin-bottom: 20px;
}

.biz-icon svg {
  width: 28px;
  height: 28px;
}

.biz-tag {
  display: inline-block;
  font-size: 12.5px;
  font-weight: 700;
  border-radius: 999px;
  padding: 4px 14px;
  margin-bottom: 14px;
}

.biz-tag-c {
  color: var(--primary);
  background: rgba(59, 47, 191, 0.08);
  border: 1px solid rgba(59, 47, 191, 0.2);
}

.biz-tag-b {
  color: #b4551d;
  background: rgba(255, 138, 66, 0.1);
  border: 1px solid rgba(255, 138, 66, 0.3);
}

.biz-card h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 12px;
}

.biz-card > p {
  font-size: 15.5px;
  color: var(--text-light);
  margin-bottom: 20px;
}

.biz-list li {
  position: relative;
  padding-left: 24px;
  margin-bottom: 8px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text);
}

.biz-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 9px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}

/* Scenes */

.scenes {
  background: var(--bg);
}

.scene-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

.scene-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.scene-image {
  overflow: hidden;
  aspect-ratio: 16 / 9.5;
  background: var(--bg-soft);
}

.scene-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.scene-card:hover .scene-image img {
  transform: scale(1.05);
}

.scene-card h3 {
  font-size: 19px;
  font-weight: 700;
  color: var(--dark);
  padding: 22px 26px 4px;
}

.scene-card p {
  font-size: 15px;
  color: var(--text-light);
  padding: 0 26px 26px;
}

/* Join */

.join {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: #fff;
}

.join-inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 56px;
  align-items: center;
}

.join-info .section-label {
  color: var(--accent-light);
}

.join-info h2 {
  color: #fff;
  margin-bottom: 16px;
}

.join-info p {
  color: rgba(255, 255, 255, 0.82);
  font-size: 16.5px;
}

.join-action {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius);
  padding: 36px;
  text-align: center;
}

.join-mail-label {
  font-size: 13px;
  letter-spacing: 1.5px;
  color: rgba(255, 255, 255, 0.6);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.join-mail {
  display: block;
  font-size: 21px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 24px;
  word-break: break-all;
}

/* Contact */

.contact {
  background: var(--bg-soft);
}

.contact-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  max-width: 1000px;
  margin: 0 auto;
}

.contact-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 8px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.contact-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(109, 92, 255, 0.4);
}

.contact-icon {
  width: 54px;
  height: 54px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  background: linear-gradient(135deg, rgba(59, 47, 191, 0.08), rgba(109, 92, 255, 0.16));
  margin-bottom: 10px;
}

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

.contact-label {
  font-size: 13px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--text-light);
}

.contact-value {
  font-size: 16px;
  font-weight: 600;
  color: var(--dark);
  max-width: 260px;
}

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

.site-footer {
  background: var(--dark);
  color: rgba(255, 255, 255, 0.75);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: 48px;
  padding: 64px 24px 44px;
}

.footer-brand .logo-mark {
  margin-bottom: 14px;
}

.footer-brand .logo-text {
  color: #fff;
  margin-left: 8px;
}

.footer-brand p {
  font-size: 14.5px;
  margin-top: 14px;
  max-width: 300px;
}

.footer-links h4 {
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.5px;
  margin-bottom: 18px;
}

.footer-links li {
  margin-bottom: 10px;
  font-size: 14.5px;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 22px 0;
  text-align: center;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.5);
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.6);
}

.footer-bottom a:hover {
  color: var(--accent-light);
}

/* ==========================================================================
   Reveal animation
   ========================================================================== */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

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

@media (max-width: 900px) {
  .about-inner,
  .join-inner {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  .section {
    padding: 64px 0;
  }

  .hero-inner {
    padding: 120px 24px 84px;
  }

  .hero-stats {
    gap: 28px;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: #14112e;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.3);
    padding: 12px 24px 20px;
    display: none;
  }

  .nav-menu.open {
    display: flex;
  }

  .nav-menu li {
    width: 100%;
  }

  .nav-menu a {
    display: block;
    padding: 12px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .nav-menu a.active::after {
    display: none;
  }

  .nav-menu .nav-cta {
    border: none;
    border-radius: 0;
    padding: 12px 0;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    padding-top: 44px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
}