/* ========================================
   银联商务电签机 - 深靛紫秒营风格
   ======================================== */

/* CSS Variables */
:root {
  --ums-indigo: #5B21B6;
  --ums-indigo-light: #7C3AED;
  --ums-indigo-dark: #4C1D95;
  --instant-orange: #F97316;
  --instant-orange-light: #FB923C;
  --direct-purple: #8B5CF6;
  --direct-purple-light: #A78BFA;
  --bg-page: #F5F3FF;
  --bg-white: #FFFFFF;
  --bg-light: #EDE9FE;
  --text-dark: #1E1B4B;
  --text-body: #334155;
  --text-light: #64748B;
  --border-light: #E2E8F0;
  --shadow-sm: 0 1px 2px rgba(91, 33, 182, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(91, 33, 182, 0.1), 0 2px 4px -2px rgba(91, 33, 182, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(91, 33, 182, 0.15), 0 4px 6px -4px rgba(91, 33, 182, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(91, 33, 182, 0.2), 0 8px 10px -6px rgba(91, 33, 182, 0.15);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --font-cn: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-en: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-cn);
  color: var(--text-body);
  background-color: var(--bg-page);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition-fast);
}

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

ul, ol {
  list-style: none;
}

/* Container */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-dark);
  font-weight: 700;
  line-height: 1.3;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.25rem; }
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-white);
  z-index: 1000;
  transition: box-shadow var(--transition-normal);
}

.navbar.scrolled {
  box-shadow: var(--shadow-lg);
}

.navbar-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

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

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--ums-indigo), var(--ums-indigo-light));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 1.25rem;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--ums-indigo);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-body);
  position: relative;
  padding: 8px 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--instant-orange);
  transition: width var(--transition-fast);
}

.nav-link:hover {
  color: var(--ums-indigo);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-link.active {
  color: var(--ums-indigo);
}

.nav-cta {
  background: linear-gradient(135deg, var(--instant-orange), var(--instant-orange-light));
  color: white;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.9rem;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(249, 115, 22, 0.4);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}

.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--ums-indigo);
  transition: transform var(--transition-fast);
}

.mobile-nav {
  display: none;
  position: fixed;
  top: 70px;
  left: 0;
  right: 0;
  background: var(--bg-white);
  padding: 20px;
  box-shadow: var(--shadow-lg);
}

.mobile-nav.active {
  display: block;
}

.mobile-nav .nav-link {
  display: block;
  padding: 12px 0;
  border-bottom: 1px solid var(--border-light);
}

.mobile-nav .nav-cta {
  display: block;
  text-align: center;
  margin-top: 16px;
}

@media (max-width: 768px) {
  .nav-links, .nav-cta:not(.mobile-nav .nav-cta) {
    display: none;
  }
  
  .mobile-menu-btn {
    display: flex;
  }
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
  min-height: 100vh;
  background: linear-gradient(135deg, var(--ums-indigo) 0%, var(--ums-indigo-light) 100%);
  display: flex;
  align-items: center;
  padding-top: 70px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 200%;
  background: radial-gradient(ellipse, rgba(124, 58, 237, 0.3) 0%, transparent 70%);
  animation: hero-glow 8s ease-in-out infinite;
}

@keyframes hero-glow {
  0%, 100% { opacity: 0.5; transform: translate(0, 0); }
  50% { opacity: 0.8; transform: translate(-5%, 5%); }
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: white;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  padding: 8px 20px;
  border-radius: 50px;
  font-size: 0.9rem;
  margin-bottom: 24px;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 20px;
  line-height: 1.2;
  color: white;
}

.hero-subtitle {
  font-size: 1.25rem;
  opacity: 0.9;
  margin-bottom: 40px;
  line-height: 1.6;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--instant-orange), var(--instant-orange-light));
  color: white;
  padding: 16px 36px;
  border-radius: var(--radius-lg);
  font-weight: 700;
  font-size: 1.1rem;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(249, 115, 22, 0.4);
}

.btn-secondary {
  background: transparent;
  color: white;
  padding: 16px 36px;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 1.1rem;
  border: 2px solid rgba(255, 255, 255, 0.5);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: white;
}

@media (max-width: 768px) {
  .hero {
    min-height: auto;
    padding: 100px 0 60px;
  }
  
  .hero-title {
    font-size: 2.25rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .hero-buttons {
    flex-direction: column;
  }
  
  .btn-primary, .btn-secondary {
    width: 100%;
    justify-content: center;
  }
}

/* Page Hero (smaller) */
.page-hero {
  background: linear-gradient(135deg, var(--ums-indigo) 0%, var(--ums-indigo-light) 100%);
  padding: 120px 0 60px;
  text-align: center;
  color: white;
  position: relative;
  overflow: hidden;
}

.page-hero.orange {
  background: linear-gradient(135deg, var(--instant-orange), var(--instant-orange-light));
}

.page-hero.purple {
  background: linear-gradient(135deg, var(--direct-purple), var(--direct-purple-light));
}

.page-hero h1 {
  color: white;
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.page-hero p {
  opacity: 0.9;
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

@media (max-width: 768px) {
  .page-hero {
    padding: 100px 0 40px;
  }
  
  .page-hero h1 {
    font-size: 1.75rem;
  }
}

/* ========================================
   Sections
   ======================================== */
.section {
  padding: 80px 0;
}

.section-dark {
  background: var(--bg-white);
}

.section-light {
  background: var(--bg-page);
}

.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  margin-bottom: 16px;
}

.section-title p {
  color: var(--text-light);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* ========================================
   Cards
   ======================================== */
.card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.card-icon.orange {
  background: linear-gradient(135deg, rgba(249, 115, 22, 0.1), rgba(249, 115, 22, 0.2));
  color: var(--instant-orange);
}

.card-icon.purple {
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.1), rgba(139, 92, 246, 0.2));
  color: var(--direct-purple);
}

.card-icon.indigo {
  background: linear-gradient(135deg, rgba(91, 33, 182, 0.1), rgba(91, 33, 182, 0.2));
  color: var(--ums-indigo);
}

.card h3 {
  margin-bottom: 12px;
}

.card p {
  color: var(--text-light);
  line-height: 1.7;
}

/* Feature Card */
.feature-card {
  position: relative;
  overflow: hidden;
}

.feature-card .card-number {
  font-family: var(--font-en);
  font-size: 4rem;
  font-weight: 800;
  color: var(--ums-indigo);
  opacity: 0.1;
  position: absolute;
  top: 16px;
  right: 20px;
  line-height: 1;
}

/* ========================================
   Layout Grid
   ======================================== */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

@media (max-width: 992px) {
  .grid-3, .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   Feature Layouts
   ======================================== */
.feature-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.feature-split.reverse {
  direction: rtl;
}

.feature-split.reverse > * {
  direction: ltr;
}

.feature-image {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.feature-content h2 {
  margin-bottom: 20px;
}

.feature-content p {
  color: var(--text-body);
  line-height: 1.8;
  margin-bottom: 24px;
}

.highlight-orange {
  color: var(--instant-orange);
  font-weight: 700;
}

.highlight-purple {
  color: var(--direct-purple);
  font-weight: 700;
}

.highlight-indigo {
  color: var(--ums-indigo);
  font-weight: 700;
}

@media (max-width: 992px) {
  .feature-split {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .feature-split.reverse {
    direction: ltr;
  }
}

/* Staggered Cards */
.cards-staggered {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.cards-staggered .card:nth-child(1) {
  width: 55%;
}

.cards-staggered .card:nth-child(2) {
  width: 43%;
  margin-left: auto;
}

.cards-staggered .card:nth-child(3) {
  width: 48%;
}

@media (max-width: 768px) {
  .cards-staggered .card {
    width: 100% !important;
    margin-left: 0 !important;
  }
}

/* ========================================
   Tables
   ======================================== */
.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-white);
}

th, td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
}

th {
  background: var(--ums-indigo);
  color: white;
  font-weight: 600;
  font-size: 0.95rem;
}

th:first-child {
  border-radius: var(--radius-lg) 0 0 0;
}

th:last-child {
  border-radius: 0 var(--radius-lg) 0 0;
}

td {
  font-size: 0.95rem;
  color: var(--text-body);
}

tr:last-child td {
  border-bottom: none;
}

tr:hover td {
  background: var(--bg-light);
}

.check {
  color: #10B981;
  font-weight: 700;
}

.cross {
  color: #EF4444;
  font-weight: 700;
}

/* ========================================
   FAQ
   ======================================== */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  font-size: 1rem;
  color: var(--text-dark);
  text-align: left;
  transition: background var(--transition-fast);
}

.faq-question:hover {
  background: var(--bg-light);
}

.faq-icon {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ums-indigo);
  transition: transform var(--transition-fast);
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-normal);
}

.faq-item.active .faq-answer {
  max-height: 300px;
}

.faq-answer-content {
  padding: 0 24px 20px;
  color: var(--text-light);
  line-height: 1.7;
}

/* ========================================
   CTA Section
   ======================================== */
.cta-section {
  background: linear-gradient(135deg, var(--ums-indigo) 0%, var(--ums-indigo-light) 100%);
  padding: 80px 0;
  text-align: center;
  color: white;
}

.cta-section h2 {
  color: white;
  margin-bottom: 16px;
}

.cta-section p {
  opacity: 0.9;
  margin-bottom: 32px;
  font-size: 1.1rem;
}

.cta-section .btn-primary {
  background: linear-gradient(135deg, var(--instant-orange), var(--instant-orange-light));
}

/* ========================================
   Footer
   ======================================== */
.footer {
  background: linear-gradient(135deg, var(--ums-indigo) 0%, var(--ums-indigo-light) 100%);
  color: white;
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 40px;
}

.footer-brand p {
  opacity: 0.8;
  margin-top: 16px;
  line-height: 1.7;
}

.footer-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: white;
}

.footer-links a {
  display: block;
  opacity: 0.8;
  padding: 6px 0;
  transition: opacity var(--transition-fast);
}

.footer-links a:hover {
  opacity: 1;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  padding-top: 24px;
  text-align: center;
  opacity: 0.7;
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}

/* ========================================
   Utility Classes
   ======================================== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-orange { color: var(--instant-orange); }
.text-purple { color: var(--direct-purple); }
.text-indigo { color: var(--ums-indigo); }
.font-bold { font-weight: 700; }
.mt-4 { margin-top: 16px; }
.mt-6 { margin-top: 24px; }
.mt-8 { margin-top: 32px; }
.mb-4 { margin-bottom: 16px; }
.mb-6 { margin-bottom: 24px; }
.mb-8 { margin-bottom: 32px; }

/* Feature Badge */
.feature-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--ums-indigo), var(--ums-indigo-light));
  color: white;
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
}

/* Stats */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-number {
  font-family: var(--font-en);
  font-size: 3rem;
  font-weight: 800;
  color: var(--ums-indigo);
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  color: var(--text-light);
  font-size: 0.95rem;
}

@media (max-width: 768px) {
  .stats-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  
  .stat-number {
    font-size: 2.5rem;
  }
}

/* Mechanism Box */
.mechanism-box {
  background: var(--bg-white);
  border-radius: var(--radius-xl);
  padding: 40px;
  box-shadow: var(--shadow-lg);
  border: 2px solid var(--bg-light);
}

.mechanism-step {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 24px 0;
  border-bottom: 1px solid var(--border-light);
}

.mechanism-step:last-child {
  border-bottom: none;
}

.step-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--ums-indigo), var(--ums-indigo-light));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.step-content h4 {
  margin-bottom: 8px;
}

.step-content p {
  color: var(--text-light);
  line-height: 1.6;
}

/* Comparison Highlight */
.compare-highlight {
  background: linear-gradient(135deg, var(--ums-indigo), var(--ums-indigo-light));
  color: white;
  padding: 4px 12px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 0.85rem;
}

.compare-highlight.orange {
  background: linear-gradient(135deg, var(--instant-orange), var(--instant-orange-light));
}

.compare-highlight.purple {
  background: linear-gradient(135deg, var(--direct-purple), var(--direct-purple-light));
}