:root {
  --brand-red: #c40e25;
  --brand-dark: #680712;
  --brand-light: #fff5f6;
  --text-primary: #2b2b2b;
  --text-muted: #5c5c5c;
  --surface: #ffffff;
  --surface-alt: #f7f7f7;
  --border-light: rgba(196, 14, 37, 0.2);
  --max-width: 1200px;
  
  /* 响应式断点 */
  --bp-sm: 640px;
  --bp-md: 768px;
  --bp-lg: 1024px;
  --bp-xl: 1200px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Plus Jakarta Sans", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text-primary);
  background: var(--surface);
  line-height: 1.6;
}

body.modal-open {
  overflow: hidden;
}

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

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

.section {
  padding: clamp(3rem, 8vw, 5.5rem) 24px;
}

.section-heading {
  max-width: 720px;
  margin: 0 auto 48px;
  text-align: center;
}

.eyebrow {
  font-size: 0.95rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--brand-dark);
  font-weight: 600;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 12px;
  line-height: 1.3;
}

label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
  color: var(--text-primary);
}

.form-field + .form-field {
  margin-top: 1rem;
}

p {
  margin: 0 0 1rem;
  color: var(--text-muted);
}

small {
  display: block;
  margin-top: 0.25rem;
  color: var(--text-muted);
}

input[type="email"],
input[type="text"] {
  width: 100%;
  padding: 0.85rem 1rem;
  border-radius: 14px;
  border: 1px solid var(--border-light);
  font-size: 1rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input[type="email"]:focus,
input[type="text"]:focus {
  outline: none;
  border-color: var(--brand-red);
  box-shadow: 0 0 0 3px rgba(196, 14, 37, 0.15);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.9rem 2rem;
  border-radius: 999px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  font-size: 1rem;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 255, 255, 0.2) 50%, 
    transparent 100%);
  transition: left 0.6s ease;
}

.btn.full {
  width: 100%;
}

.btn:disabled,
.btn[disabled] {
  opacity: 0.4;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn.primary {
  background: linear-gradient(135deg, 
    var(--brand-red) 0%, 
    #ff3366 100%);
  color: #fff;
  box-shadow: 0 8px 24px rgba(196, 14, 37, 0.25),
              0 4px 12px rgba(196, 14, 37, 0.15),
              inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.btn.primary:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(196, 14, 37, 0.35),
              0 6px 16px rgba(196, 14, 37, 0.2),
              inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.btn.primary:hover:not(:disabled)::before {
  left: 100%;
}

.btn.ghost {
  border-color: var(--brand-red);
  color: var(--brand-red);
  background: transparent;
  position: relative;
}

.btn.ghost:hover:not(:disabled) {
  background: rgba(196, 14, 37, 0.08);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(196, 14, 37, 0.12);
}

.btn.ghost:hover:not(:disabled)::before {
  left: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: linear-gradient(135deg, 
    rgba(255, 255, 255, 0.98) 0%, 
    rgba(255, 255, 255, 0.95) 100%);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(196, 14, 37, 0.08);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08),
              0 1px 3px rgba(196, 14, 37, 0.05);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--brand-red);
  letter-spacing: 0.08em;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  transition: all 0.3s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

.site-nav a {
  position: relative;
  padding-bottom: 6px;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  transition: all 0.3s ease;
  font-weight: 500;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: var(--brand-red);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.2s ease;
}

.site-nav a:hover {
  background: rgba(196, 14, 37, 0.08);
  transform: translateY(-1px);
}

.site-nav a:hover::after {
  transform: scaleX(1);
}

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

.nav-toggle span {
  width: 28px;
  height: 2px;
  background: var(--text-primary);
}

.hero {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 48px;
  padding: clamp(4rem, 10vw, 7rem) 24px 4rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.hero-content h1 {
  font-size: clamp(2.5rem, 5vw, 3.8rem);
  color: var(--brand-red);
}

.brand-mark {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  background: #fff;
  box-shadow: 0 20px 40px rgba(196, 14, 37, 0.18);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}

.brand-mark img {
  width: 40px;
  height: 40px;
}

.lead {
  font-size: 1.1rem;
  color: #383838;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1.5rem 0;
}

.tag {
  border: 1px solid rgba(196, 14, 37, 0.15);
  padding: 0.5rem 1.2rem;
  border-radius: 999px;
  font-size: 0.9rem;
  color: var(--brand-red);
  background: linear-gradient(135deg, 
    var(--brand-light) 0%, 
    rgba(196, 14, 37, 0.08) 100%);
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.tag::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 255, 255, 0.3) 50%, 
    transparent 100%);
  transition: left 0.6s ease;
}

.tag:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(196, 14, 37, 0.15);
  border-color: rgba(196, 14, 37, 0.3);
}

.tag:hover::before {
  left: 100%;
}

.hero-visual {
  background: linear-gradient(135deg, 
    #fff 0%, 
    #ffe4e7 30%,
    #ffd1d7 70%,
    #fff5f7 100%);
  border-radius: 32px;
  padding: 2.5rem;
  position: relative;
  overflow: hidden;
  min-height: 340px;
  box-shadow: 0 20px 60px rgba(196, 14, 37, 0.15),
              0 8px 24px rgba(0, 0, 0, 0.08),
              inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.hero-visual::after {
  content: "";
  position: absolute;
  inset: 16px;
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: 24px;
  background: linear-gradient(135deg, 
    rgba(255, 255, 255, 0.1) 0%, 
    transparent 50%, 
    rgba(255, 255, 255, 0.05) 100%);
  box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.05);
}

.hero-visual::before {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at center, 
    rgba(196, 14, 37, 0.03) 0%, 
    transparent 40%);
  animation: heroFloat 8s ease-in-out infinite;
  pointer-events: none;
}

@keyframes heroFloat {
  0%, 100% {
    transform: translate(0, 0) rotate(0deg);
  }
  50% {
    transform: translate(-10px, -5px) rotate(180deg);
  }
}

.orbital {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}

.orbital span {
  position: absolute;
  border: 1px solid rgba(196, 14, 37, 0.4);
  border-radius: 50%;
  animation: pulse 8s linear infinite;
}

.orbital span:nth-child(1) {
  width: 120px;
  height: 120px;
}

.orbital span:nth-child(2) {
  width: 200px;
  height: 200px;
  animation-delay: 0.8s;
}

.orbital span:nth-child(3) {
  width: 280px;
  height: 280px;
  animation-delay: 1.6s;
}

@keyframes pulse {
  0% {
    transform: scale(0.9);
    opacity: 0.5;
  }
  50% {
    transform: scale(1);
    opacity: 1;
  }
  100% {
    transform: scale(1.1);
    opacity: 0.4;
  }
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.card {
  background: linear-gradient(135deg, 
    var(--surface) 0%, 
    rgba(255, 255, 255, 0.8) 50%, 
    var(--surface) 100%);
  border-radius: 24px;
  padding: 2rem;
  border-top: 4px solid var(--brand-red);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.06),
              0 8px 24px rgba(0, 0, 0, 0.04),
              inset 0 1px 0 rgba(255, 255, 255, 0.5);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 255, 255, 0.2) 50%, 
    transparent 100%);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.08),
              0 12px 30px rgba(0, 0, 0, 0.06),
              inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

.activities {
  background: var(--surface-alt);
}

.timeline {
  display: grid;
  gap: 1.5rem;
  max-width: 840px;
  margin: 0 auto;
}

.timeline-item {
  background: linear-gradient(135deg, 
    #ffffff 0%, 
    #fafafa 50%, 
    #ffffff 100%);
  border-radius: 20px;
  padding: 2rem;
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 1.5rem;
  align-items: center;
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: 0 24px 50px rgba(0, 0, 0, 0.06),
              0 8px 24px rgba(0, 0, 0, 0.04),
              inset 0 1px 0 rgba(255, 255, 255, 0.8);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.timeline-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(196, 14, 37, 0.1) 50%, 
    transparent 100%);
}

@media (max-width: 768px) {
  .timeline-item {
    grid-template-columns: auto 1fr;
    gap: 0.75rem;
    padding: 1.5rem;
  }
  
  .timeline-item span {
    display: none;
  }
}

@media (max-width: 480px) {
  .timeline-item {
    padding: 1.25rem;
    text-align: left;
  }
  
  .timeline-dot {
    width: 12px;
    height: 12px;
  }
}

.timeline-dot {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: linear-gradient(135deg, 
    var(--brand-red) 0%, 
    #ff3366 100%);
  box-shadow: 0 0 0 4px rgba(196, 14, 37, 0.2),
              0 0 8px rgba(196, 14, 37, 0.1);
  position: relative;
}

.timeline-dot::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 6px;
  height: 6px;
  background: #ffffff;
  border-radius: 50%;
  opacity: 0.9;
}

.timeline-item span {
  font-weight: 600;
  color: var(--brand-dark);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.feature-card {
  background: linear-gradient(180deg, #fff, #fff7f8);
  border-radius: 18px;
  padding: 1.75rem;
  border: 1px solid rgba(196, 14, 37, 0.15);
  min-height: 220px;
}

.join {
  background: var(--surface-alt);
}

.join-card {
  max-width: 720px;
  margin: 0 auto;
  background: #fff;
  padding: clamp(2rem, 6vw, 3.5rem);
  border-radius: 28px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.08);
}

.join-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1rem;
}

.join-actions .btn {
  min-width: 200px;
}

.contact-block {
  border-left: 4px solid var(--brand-red);
  padding-left: 1.2rem;
  margin-bottom: 1.5rem;
}

.notice {
  margin-top: 1.5rem;
  padding: 1rem 1.25rem;
  border-radius: 12px;
  background: var(--brand-light);
  color: var(--brand-dark);
  font-weight: 600;
}

/* 成员福利区域 */
.subdomain-section {
  background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
  border-top: 3px solid var(--brand-red);
  position: relative;
}

.subdomain-section::before {
  content: '';
  position: absolute;
  top: -1.5px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--brand-red);
  color: white;
  padding: 4px 16px;
  border-radius: 0 0 8px 8px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  z-index: 1;
  content: '成员福利';
}

/* 福利卡片通用样式 */
.benefit-card {
  max-width: 800px;
  margin: 0 auto 3rem;
  background: #fff;
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.08);
  border: 1px solid rgba(196, 14, 37, 0.1);
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2rem;
  align-items: start;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.benefit-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.12);
}

.benefit-card:last-child {
  margin-bottom: 0;
}

.benefit-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 80px;
  height: 80px;
  background: var(--brand-light);
  border-radius: 20px;
  flex-shrink: 0;
}

.benefit-icon svg {
  width: 40px;
  height: 40px;
}

.benefit-content h3 {
  font-size: 1.5rem;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.benefit-example {
  font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
  font-size: 1.2rem;
  color: var(--brand-red);
  font-weight: 600;
  background: var(--brand-light);
  padding: 0.5rem 1rem;
  border-radius: 8px;
  margin: 0.5rem 0 1rem;
  display: inline-block;
}

.benefit-uses {
  margin: 1rem 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
}

.benefit-uses li {
  color: var(--text-muted);
  padding: 0.5rem 0;
  padding-left: 1.5rem;
  position: relative;
  font-size: 0.95rem;
}

.benefit-uses li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--brand-red);
  font-weight: bold;
}

.benefit-highlight {
  display: flex;
  gap: 0.5rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

/* 第二个福利卡片特殊颜色 */
.benefit-card:nth-child(2) .benefit-icon {
  background: rgba(25, 118, 210, 0.1);
}

.benefit-card:nth-child(2) .benefit-example {
  color: #1976d2;
  background: rgba(25, 118, 210, 0.1);
}

.benefit-card:nth-child(2) .benefit-uses li::before {
  color: #1976d2;
}

/* 第三个福利卡片特殊颜色 */
.benefit-card:nth-child(3) .benefit-icon {
  background: rgba(156, 39, 176, 0.1);
}

.benefit-card:nth-child(3) .benefit-example {
  color: #9c27b0;
  background: rgba(156, 39, 176, 0.1);
}

.benefit-card:nth-child(3) .benefit-uses li::before {
  color: #9c27b0;
}

/* 第四个福利卡片特殊颜色 - 网络环境主题 */
.benefit-card:nth-child(4) .benefit-icon {
  background: linear-gradient(135deg, 
    rgba(66, 133, 244, 0.1) 0%, 
    rgba(147, 51, 234, 0.1) 100%);
}

.benefit-card:nth-child(4) .benefit-example {
  color: #6366f1;
  background: linear-gradient(135deg, 
    rgba(66, 133, 244, 0.1) 0%, 
    rgba(147, 51, 234, 0.1) 100%);
}

.benefit-card:nth-child(4) .benefit-uses li::before {
  color: #6366f1;
}

.highlight-tag {
  background: linear-gradient(135deg, var(--brand-red), var(--brand-dark));
  color: white;
  padding: 0.4rem 0.8rem;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
}

/* 学习平台区域 */
.learning-platform {
  background: linear-gradient(135deg, #f0f8ff 0%, #e6f3ff 100%);
  position: relative;
}

.learning-platform .section-heading {
  text-align: center;
}

.learning-platform .platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
  max-width: 1400px;
  margin-left: auto;
  margin-right: auto;
  padding: 0 24px;
}

.platform-feature {
  background: #fff;
  border-radius: 20px;
  padding: 2rem;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.08);
  border: 1px solid rgba(66, 153, 225, 0.2);
  text-align: center;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
}

.platform-feature:hover {
  transform: translateY(-4px);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.12),
              0 12px 30px rgba(0, 0, 0, 0.08);
  border-color: rgba(66, 153, 225, 0.3);
}

.platform-feature::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(66, 153, 225, 0.1) 50%, 
    transparent 100%);
}

.platform-content {
  display: flex;
  flex-direction: column;
  height: 100%;
  text-align: center;
}

.platform-content h3 {
  font-size: 1.5rem;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

.platform-content > p {
  margin-bottom: 1rem;
  line-height: 1.6;
  color: var(--text-muted);
  font-size: 0.95rem;
  text-align: center;
}

.platform-url {
  font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
  font-size: 1.1rem;
  color: #1976d2;
  font-weight: 600;
  background: #e3f2fd;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  margin: 0.75rem 0;
  display: inline-block;
}

.platform-features {
  margin: 1rem 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  text-align: left;
  align-items: flex-start;
}

.platform-features li {
  color: var(--text-muted);
  padding: 0.4rem 0;
  padding-left: 1.6rem;
  position: relative;
  font-size: 0.9rem;
  line-height: 1.4;
}

.platform-features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: #1976d2;
  font-weight: bold;
  font-size: 1rem;
}

.platform-actions {
  margin-top: 1.5rem;
}

/* 第二个平台特殊样式 */
.platform-feature:nth-child(2) {
  border-color: rgba(255, 140, 0, 0.2);
}

.platform-feature:nth-child(2) .platform-url {
  color: #ff8c00;
  background: rgba(255, 140, 0, 0.1);
}

.platform-feature:nth-child(2)::before {
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 140, 0, 0.1) 50%, 
    transparent 100%);
}

/* 第三个平台特殊样式 - 阿里云培训中心 */
.platform-feature:nth-child(3) {
  border-color: rgba(255, 69, 0, 0.2);
}

.platform-feature:nth-child(3) .platform-url {
  color: #ff4500;
  background: rgba(255, 69, 0, 0.1);
}

.platform-feature:nth-child(3)::before {
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 69, 0, 0.1) 50%, 
    transparent 100%);
}

.platform-feature:nth-child(3) .platform-link {
  background: linear-gradient(135deg, #ff4500, #ff6347);
}

.platform-feature:nth-child(3) .platform-link:hover {
  box-shadow: 0 8px 20px rgba(255, 69, 0, 0.3);
}

.platform-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, #1976d2, #1565c0);
  color: white;
  text-decoration: none;
  padding: 0.8rem 1.5rem;
  border-radius: 25px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.3s ease;
}

.platform-link:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(25, 118, 210, 0.3);
}

.platform-link svg {
  transition: transform 0.3s ease;
}

.platform-link:hover svg {
  transform: translate(2px, -2px);
}

@media (max-width: 1200px) {
  .learning-platform .platform-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
  }
}

@media (max-width: 768px) {
  .platform-feature {
    padding: 1.5rem;
  }
  
  .platform-features {
    text-align: left;
  }
  
  .platform-features li {
    padding-left: 1.5rem;
    text-align: left;
  }
  
  .platform-link {
    width: 100%;
    justify-content: center;
  }
  
  .learning-platform .platform-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 480px) {
  .platform-feature {
    padding: 1.25rem;
  }
  
  .platform-url {
    font-size: 0.95rem;
    padding: 0.4rem 0.8rem;
  }
  
  .platform-features li {
    font-size: 0.85rem;
    padding: 0.35rem 0;
  }
  
  .platform-content h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
  }
}

@media (max-width: 768px) {
  .benefit-card {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 1.5rem;
    padding: 2rem;
  }
  
  .benefit-icon {
    margin: 0 auto;
  }
  
  .benefit-uses {
    grid-template-columns: 1fr;
  }
  
  .benefit-highlight {
    justify-content: center;
  }
  
  .platform-feature {
    padding: 2rem;
  }
  
  .platform-features {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .platform-link {
    width: 100%;
    justify-content: center;
  }
  
  .learning-platform .platform-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 480px) {
  .benefit-card {
    padding: 1.5rem;
  }
  
  .benefit-example {
    font-size: 1rem;
    padding: 0.4rem 0.8rem;
  }
  
  .highlight-tag {
    font-size: 0.75rem;
    padding: 0.3rem 0.6rem;
  }
}

.special-recruits-section {
  background: linear-gradient(135deg, var(--brand-light) 0%, var(--surface) 100%);
  padding: clamp(3rem, 8vw, 5.5rem) 24px;
  border-top: 4px solid var(--brand-red);
  box-shadow: 0 -4px 20px rgba(196, 14, 37, 0.08);
  position: relative;
}

.special-recruits-section::before {
  content: '';
  position: absolute;
  top: -2px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--brand-red);
  color: white;
  padding: 4px 20px;
  border-radius: 0 0 12px 12px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  z-index: 1;
}

.special-recruits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  max-width: 1200px;
  margin: 2rem auto 0;
}

@media (max-width: 768px) {
  .special-recruits-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 480px) {
  .special-recruits-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
}

.special-recruit-card {
  background: var(--surface);
  border-radius: 16px;
  padding: 2rem;
  border: 1px solid var(--border-light);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
}

.special-recruit-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--brand-red), var(--brand-dark));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.special-recruit-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.12);
}

.special-recruit-card:hover::before {
  opacity: 1;
}

.recruit-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  line-height: 1;
}

.recruit-icon svg {
  width: 48px;
  height: 48px;
}

@media (max-width: 768px) {
  .recruit-icon svg {
    width: 40px;
    height: 40px;
  }
}

@media (max-width: 480px) {
  .recruit-icon svg {
    width: 36px;
    height: 36px;
  }
  
  .special-recruit-card {
    padding: 1.5rem;
  }
}

.special-recruit-card h3 {
  margin: 0 0 0.5rem 0;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
}

.recruit-subtitle {
  font-size: 0.875rem;
  color: var(--brand-red);
  font-weight: 500;
  margin: 0 0 1rem 0;
}

.special-recruit-card p {
  margin: 0 0 1.5rem 0;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.recruit-tag {
  display: inline-block;
  background: var(--brand-light);
  color: var(--brand-dark);
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
}

/* 美化表单控件 */
.form-field select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border-light);
  border-radius: 8px;
  font-family: inherit;
  font-size: 1rem;
  background: var(--surface);
  color: var(--text-primary);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
  appearance: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%23c40e25' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
  background-position: right 12px center;
  background-repeat: no-repeat;
  background-size: 16px;
  padding-right: 44px;
}

.form-field select:hover {
  border-color: var(--brand-red);
}

.form-field select:focus {
  outline: none;
  border-color: var(--brand-red);
  box-shadow: 0 0 0 3px rgba(196, 14, 37, 0.1);
}

.form-field select option {
  background: var(--surface);
  color: var(--text-primary);
  padding: 12px;
}

/* 为选中的方向添加视觉反馈 */
.form-field select:valid {
  border-color: var(--brand-red);
}

.email-modal {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.email-modal[data-open="true"] {
  opacity: 1;
  pointer-events: auto;
}

.modal-overlay {
  position: absolute;
  inset: 0;
}

.modal-panel {
  position: relative;
  width: min(520px, 100%);
  background: #fff;
  border-radius: 28px;
  padding: clamp(2rem, 4vw, 3rem);
  box-shadow: 0 40px 80px rgba(0, 0, 0, 0.15);
  z-index: 1;
  margin: 1rem;
}

@media (max-width: 640px) {
  .modal-panel {
    width: calc(100% - 2rem);
    margin: 1rem;
    padding: 2rem 1.5rem;
  }
  
  .modal-close {
    top: 12px;
    right: 16px;
    font-size: 1.5rem;
  }
}

.modal-close {
  position: absolute;
  top: 16px;
  right: 20px;
  border: none;
  background: transparent;
  font-size: 1.8rem;
  line-height: 1;
  cursor: pointer;
  color: var(--text-muted);
  transition: all 0.3s ease;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-close:hover {
  color: var(--brand-red);
  background: rgba(196, 14, 37, 0.1);
  transform: rotate(90deg);
}

.modal-close:active {
  transform: rotate(180deg) scale(0.95);
}

/* QQ模态框关闭按钮特殊样式 */
#qq-modal .modal-close {
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.05) 0%, 
    rgba(255, 107, 107, 0.02) 100%);
  border: 1px solid rgba(196, 14, 37, 0.1);
  color: var(--brand-red);
}

#qq-modal .modal-close:hover {
  background: var(--brand-red);
  color: white;
  box-shadow: 0 4px 12px rgba(196, 14, 37, 0.3);
}

.modal-lead {
  color: var(--text-primary);
  margin-bottom: 1.5rem;
}

.modal-hint {
  margin: 1rem 0 0.5rem;
  color: var(--text-muted);
}

.modal-actions {
  display: grid;
  gap: 0.75rem;
  margin: 1.25rem 0 0.5rem;
}

.form-feedback {
  min-height: 1.4rem;
  font-weight: 600;
  color: var(--brand-dark);
}

.form-feedback.error {
  color: #b00020;
}

.site-footer {
  background: linear-gradient(180deg, 
    #1a1a1a 0%, 
    #161616 30%,
    #121212 60%,
    #0f0f0f 100%);
  color: #efefef;
  position: relative;
  border-top: 2px solid var(--brand-red);
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    var(--brand-red) 50%, 
    transparent 100%);
  box-shadow: 0 0 10px rgba(196, 14, 37, 0.5);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3.5rem 24px 2.5rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2.5rem;
  position: relative;
}

.footer-inner::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100px;
  height: 100px;
  background: radial-gradient(circle, 
    rgba(196, 14, 37, 0.05) 0%, 
    transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

.footer-section {
  position: relative;
  z-index: 1;
}

.footer-section h3 {
  color: #ffffff;
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 1.2rem;
  position: relative;
  display: inline-block;
  letter-spacing: -0.02em;
}

.footer-section h3::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, 
    var(--brand-red) 0%, 
    transparent 100%);
  border-radius: 1px;
}

.footer-section p {
  color: #b8b8b8;
  margin-bottom: 1rem;
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 1rem;
}

.footer-links a {
  color: #d2d2d2;
  text-decoration: none;
  font-size: 0.9rem;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  position: relative;
  padding: 0.4rem 0;
  font-weight: 400;
}

.footer-links a::before {
  content: '▸';
  color: var(--brand-red);
  margin-right: 0.5rem;
  font-size: 0.9rem;
  transition: transform 0.3s ease;
  opacity: 0.7;
}

.footer-links a:hover {
  color: #ffffff;
  transform: translateX(4px);
}

.footer-links a:hover::before {
  transform: translateX(2px);
  opacity: 1;
}

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

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1rem;
}

.tech-tags a,
.tech-tags span {
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.12) 0%, 
    rgba(196, 14, 37, 0.08) 100%);
  color: #e8e8e8;
  padding: 0.4rem 0.9rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid rgba(196, 14, 37, 0.2);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  text-decoration: none;
  display: inline-block;
}

.tech-tags span {
  background: transparent;
  color: #888;
  border: none;
  padding: 0.4rem 0.5rem;
  pointer-events: none;
}

.tech-tags a::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(255, 255, 255, 0.1) 50%, 
    transparent 100%);
  transition: left 0.5s ease;
}

.tech-tags a:hover {
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.25) 0%, 
    rgba(196, 14, 37, 0.18) 100%);
  color: #ffffff;
  border-color: rgba(196, 14, 37, 0.4);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(196, 14, 37, 0.2);
}

.tech-tags a:hover::before {
  left: 100%;
}

.contact-info {
  margin-top: 1rem;
}

.contact-info p {
  color: #d2d2d2;
  margin-bottom: 0.8rem;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.8rem;
  position: relative;
  padding: 0.5rem 0;
  transition: all 0.3s ease;
}

.contact-info p::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--brand-red);
  border-radius: 50%;
  flex-shrink: 0;
  box-shadow: 0 0 6px rgba(196, 14, 37, 0.4);
}

.contact-info p:hover {
  color: #ffffff;
  transform: translateX(3px);
}

.contact-info p a {
  color: #4fc3f7;
  text-decoration: none;
  transition: all 0.3s ease;
  border-bottom: 1px solid transparent;
}

.contact-info p a:hover {
  color: #29b6f6;
  border-bottom-color: #29b6f6;
}

.contact-info p[data-tg-modal-open] {
  cursor: pointer;
  user-select: none;
}

.contact-info p[data-tg-modal-open]:hover {
  color: #4fc3f7;
  transform: translateX(3px);
}

.contact-info p[data-tg-modal-open]::before {
  background: #6366f1;
  box-shadow: 0 0 6px rgba(99, 102, 241, 0.4);
}

.social-links {
  display: flex;
  gap: 1rem;
}

.social-links a {
  color: #d2d2d2;
  text-decoration: none;
  font-size: 0.9rem;
  padding: 0.5rem 1rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  transition: all 0.2s ease;
}

.qq-contact {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.2rem;
  padding: 1.5rem;
  background: rgba(255, 255, 255, 0.03);
  border-radius: 24px;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  position: relative;
}

.qq-contact::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.03) 0%, 
    rgba(255, 107, 107, 0.01) 100%);
  border-radius: 24px;
  z-index: -1;
}

.qq-background {
  width: 140px;
  height: 140px;
  border-radius: 20px;
  border: 3px solid transparent;
  background: linear-gradient(white, white) padding-box,
              linear-gradient(135deg, var(--brand-red), #ff6b6b) border-box;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  object-fit: cover;
  object-position: top center;
  position: relative;
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(196, 14, 37, 0.15);
}

.qq-background::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.1) 0%, 
    rgba(255, 107, 107, 0.05) 50%, 
    rgba(196, 14, 37, 0) 100%);
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
}

.qq-background:hover {
  transform: scale(1.08) translateY(-4px);
  box-shadow: 0 12px 32px rgba(196, 14, 37, 0.25),
              0 0 0 1px rgba(196, 14, 37, 0.2);
}

.qq-background:hover::before {
  opacity: 1;
}

.qq-background:active {
  transform: scale(1.02) translateY(-2px);
}

.qq-background:hover {
  border-color: var(--brand-red);
  transform: scale(1.05);
}

.qq-note {
  color: #e8e8e8;
  font-size: 0.9rem;
  margin: 0;
  text-align: center;
  font-weight: 500;
  letter-spacing: 0.5px;
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.qq-note::before {
  content: '👆';
  font-size: 1rem;
  animation: bounce 2s infinite;
  display: inline-block;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0);
  }
  40% {
    transform: translateY(-4px);
  }
  60% {
    transform: translateY(-2px);
  }
}

/* QQ模态框样式 */
.qq-modal {
  position: fixed;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  padding: 24px;
  background: radial-gradient(circle at center, 
    rgba(196, 14, 37, 0.12) 0%, 
    rgba(0, 0, 0, 0.85) 100%);
  backdrop-filter: blur(12px);
  opacity: 0;
  pointer-events: none;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  animation: modalPulse 3s ease-in-out infinite paused;
}

.qq-modal[data-open="true"] {
  opacity: 1;
  pointer-events: auto;
  animation-play-state: running;
}

@keyframes modalPulse {
  0%, 100% {
    background: radial-gradient(circle at center, 
      rgba(196, 14, 37, 0.12) 0%, 
      rgba(0, 0, 0, 0.85) 100%);
  }
  50% {
    background: radial-gradient(circle at center, 
      rgba(196, 14, 37, 0.18) 0%, 
      rgba(0, 0, 0, 0.88) 100%);
  }
}

.qq-modal-panel {
  position: relative;
  width: min(420px, 100%);
  background: linear-gradient(135deg, 
    #ffffff 0%, 
    #fafafa 30%,
    #fef5f5 50%,
    #fafafa 70%,
    #ffffff 100%);
  border-radius: 24px;
  padding: clamp(2rem, 4vw, 2.5rem);
  box-shadow: 0 60px 120px rgba(0, 0, 0, 0.25),
              0 30px 60px rgba(196, 14, 37, 0.12),
              0 10px 20px rgba(196, 14, 37, 0.08),
              inset 0 1px 0 rgba(255, 255, 255, 0.9),
              inset 0 -1px 0 rgba(196, 14, 37, 0.05);
  z-index: 1;
  margin: 1rem;
  text-align: center;
  border: 1px solid rgba(196, 14, 37, 0.08);
  backdrop-filter: blur(20px);
  transform: scale(0.8) translateY(20px);
  opacity: 0;
  transition: all 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.qq-modal[data-open="true"] .qq-modal-panel {
  transform: scale(1) translateY(0);
  opacity: 1;
}

.qq-qr-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  padding: 2rem;
  background: linear-gradient(135deg, 
    rgba(196, 14, 37, 0.03) 0%, 
    rgba(255, 107, 107, 0.02) 50%,
    rgba(196, 14, 37, 0.03) 100%);
  border-radius: 24px;
  position: relative;
  border: 2px solid transparent;
  background-clip: padding-box;
}

.qq-qr-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, 
    rgba(255, 255, 255, 0.9) 0%, 
    rgba(255, 255, 255, 0.95) 50%,
    rgba(255, 255, 255, 0.9) 100%);
  border-radius: 22px;
  z-index: -1;
  box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.04),
              0 0 0 1px rgba(196, 14, 37, 0.08);
}

.qq-qr-container::after {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  background: linear-gradient(135deg, 
    var(--brand-red) 0%, 
    #ff6b6b 25%, 
    var(--brand-dark) 75%, 
    var(--brand-red) 100%);
  border-radius: 24px;
  z-index: -2;
  animation: containerGlow 3s linear infinite;
}

@keyframes containerGlow {
  0%, 100% {
    opacity: 0.3;
    filter: blur(8px);
  }
  50% {
    opacity: 0.6;
    filter: blur(6px);
  }
}

.qq-modal-qr {
  width: 220px;
  height: 220px;
  border-radius: 20px;
  border: 4px solid transparent;
  background: linear-gradient(white, white) padding-box,
              linear-gradient(135deg, var(--brand-red), #ff6b6b, var(--brand-dark)) border-box;
  object-fit: cover;
  object-position: center 60%;
  /* 进一步减少裁剪，确保二维码完全显示 */
  clip-path: inset(2% 2% 2% 2%);
  box-shadow: 0 12px 32px rgba(196, 14, 37, 0.15),
              0 0 0 1px rgba(196, 14, 37, 0.1),
              inset 0 0 0 1px rgba(255, 255, 255, 0.3);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.qq-modal-qr::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, 
    rgba(255, 255, 255, 0.2) 0%, 
    rgba(255, 255, 255, 0.1) 50%, 
    rgba(255, 255, 255, 0) 100%);
  pointer-events: none;
  border-radius: 16px;
}

.qq-modal-qr:hover {
  transform: scale(1.02) rotate(1deg);
  box-shadow: 0 16px 40px rgba(196, 14, 37, 0.2),
              0 0 0 1px rgba(196, 14, 37, 0.2),
              inset 0 0 0 1px rgba(255, 255, 255, 0.4);
}

#qq-modal-title {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--brand-red);
  margin: 0 0 1.5rem 0;
  position: relative;
  text-align: center;
  letter-spacing: -0.02em;
}

#qq-modal-title::after {
  content: '';
  position: absolute;
  bottom: -0.75rem;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    var(--brand-red) 50%, 
    transparent 100%);
  border-radius: 2px;
}

.qq-modal-note {
  color: #444;
  font-size: 1rem;
  margin: 0;
  font-weight: 500;
  text-align: center;
  position: relative;
  display: block;
  width: 100%;
  margin-top: 0.5rem;
}

.qq-modal-note::after {
  content: '';
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    var(--brand-red) 50%, 
    transparent 100%);
  margin-top: 0.5rem;
}

/* Telegram模态框特殊样式 - 仅显示二维码 */
#tg-modal .qq-modal-panel {
  border-color: rgba(99, 102, 241, 0.2);
  padding: 1.25rem;
  text-align: center;
  position: relative;
  max-height: 90vh;
  overflow-y: auto;
}

#tg-modal .qq-qr-container {
  padding: 0;
  background: transparent;
  border: none;
  display: flex;
  flex-direction: column;
  align-items: center;
}

#tg-modal .qq-qr-container::before,
#tg-modal .qq-qr-container::after {
  display: none;
}

#tg-modal .tg-qr-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 0.5rem;
}

#tg-modal .tg-qr-label {
  font-size: 0.85rem;
  color: #666;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

#tg-modal .qq-modal-qr {
  border: 3px solid transparent;
  background: linear-gradient(white, white) padding-box,
              linear-gradient(135deg, #6366f1, #8b5cf6, #6366f1) border-box;
  width: 180px;
  height: 180px;
  margin: 0;
  display: block;
  border-radius: 16px;
  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.15),
              0 0 0 1px rgba(99, 102, 241, 0.1),
              inset 0 0 0 1px rgba(255, 255, 255, 0.3);
  object-fit: cover;
  object-position: center;
  clip-path: inset(0% 5% 5% 5%);
}

#tg-modal .tg-qr-small {
  width: 180px;
  height: 180px;
}

#tg-modal .qq-modal-note {
  margin-top: 0.75rem;
  color: #666;
  font-size: 0.85rem;
  line-height: 1.4;
}

#tg-modal .tg-qr-section:last-of-type {
  margin-bottom: 0;
}

#tg-modal .modal-close {
  background: linear-gradient(135deg, 
    rgba(99, 102, 241, 0.05) 0%, 
    rgba(139, 92, 246, 0.02) 100%);
  border: 1px solid rgba(99, 102, 241, 0.1);
  color: #6366f1;
}

#tg-modal .modal-close:hover {
  background: #6366f1;
  color: white;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

#tg-modal .qq-qr-container p {
  text-align: center;
  margin: 0;
  line-height: 1.4;
}

#tg-modal .qq-qr-container p:last-child {
  margin-top: 0.5rem;
}

#tg-modal .qq-qr-container a {
  color: #6366f1;
  text-decoration: none;
  transition: all 0.3s ease;
  border-bottom: 1px solid transparent;
  display: inline-block;
  padding: 0.4rem 0.9rem;
  border-radius: 8px;
  background: rgba(99, 102, 241, 0.05);
  font-size: 0.9rem;
}

#tg-modal .qq-qr-container a:hover {
  color: #4f46e5;
  border-bottom-color: #4f46e5;
  background: rgba(99, 102, 241, 0.1);
  transform: translateY(-1px);
  box-shadow: 0 3px 8px rgba(99, 102, 241, 0.2);
}

@media (max-width: 640px) {
  .qq-modal-panel {
    width: calc(100% - 2rem);
    margin: 1rem;
    padding: 1.5rem;
  }
  
  .qq-modal-qr {
    width: 180px;
    height: 180px;
    clip-path: inset(2% 2% 2% 2%);
    border-width: 3px;
  }
}

.footer-bottom {
  background: linear-gradient(180deg, 
    #0d0d0d 0%, 
    #0a0a0a 100%);
  border-top: 1px solid rgba(196, 14, 37, 0.2);
  margin-top: 2rem;
  position: relative;
}

.footer-bottom::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, 
    transparent 0%, 
    rgba(196, 14, 37, 0.3) 50%, 
    transparent 100%);
}

.footer-bottom-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
  position: relative;
}

.footer-bottom-inner p {
  margin: 0;
  color: #8a8a8a;
  font-size: 0.85rem;
}

.footer-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: #8a8a8a;
  font-size: 0.85rem;
}

.footer-meta a {
  color: #a8a8a8;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-meta a:hover {
  color: var(--brand-red);
}

@media (max-width: 768px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 2.5rem 24px 1.5rem;
  }
  
  .footer-section h3::after {
    left: 50%;
    transform: translateX(-50%);
  }
  
  .footer-links {
    align-items: center;
  }
  
  .tech-tags {
    justify-content: center;
  }
  
  .social-links {
    justify-content: center;
  }
  
  .contact-info p {
    justify-content: center;
  }
  
  .qq-background {
    width: 110px;
    height: 110px;
    border-radius: 16px;
    border-width: 2px;
    object-position: top center;
  }
  
  .footer-bottom-inner {
    flex-direction: column;
    text-align: center;
    gap: 0.5rem;
  }
  
  .footer-meta {
    flex-direction: column;
    gap: 0.25rem;
  }
}

@media (max-width: 480px) {
  .footer-inner {
    padding: 2rem 24px 1rem;
    gap: 1.5rem;
  }
  
  .social-links {
    flex-direction: column;
    width: 100%;
  }
  
  .social-links a {
    text-align: center;
    width: 100%;
  }
  
  .qq-contact {
    padding: 1rem;
    gap: 1rem;
  }
}

@media (max-width: 960px) {
  .site-nav {
    position: absolute;
    top: 72px;
    right: 24px;
    flex-direction: column;
    padding: 1.5rem;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.1);
    min-width: 200px;
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 0.2s ease, transform 0.2s ease;
  }

  .site-nav[data-visible="true"] {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav-toggle {
    display: flex;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  
  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 24px;
    right: 24px;
    flex-direction: column;
    background: var(--surface);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
    border: 1px solid var(--border-light);
    gap: 1rem;
    margin-top: 0.5rem;
    z-index: 5;
  }
  
  .site-nav[data-visible="true"] {
    display: flex;
  }
}

@media (max-width: 640px) {
  .hero {
    padding-top: 5.5rem;
  }
  
  .hero-content {
    text-align: center;
  }
  
  .hero-tags {
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
  }
  
  .hero-visual p {
    text-align: center;
    font-size: 0.95rem;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(12px);
    padding: 1rem 1.2rem;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.15);
    color: #f8f8f8;
    position: relative;
    z-index: 2;
    font-weight: 500;
    letter-spacing: 0.02em;
    line-height: 1.6;
  }

  .timeline-item {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* AI助手固定按钮 - 美化样式 */
.ai-chat-fab {
  position: fixed !important;
  bottom: 30px !important;
  right: 30px !important;
  left: auto !important;
  top: auto !important;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: linear-gradient(135deg, 
    var(--brand-red) 0%, 
    #ff3366 50%,
    var(--brand-dark) 100%);
  color: #ffffff;
  border: 3px solid rgba(255, 255, 255, 0.3);
  cursor: pointer;
  display: flex !important;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 24px rgba(196, 14, 37, 0.4),
              0 4px 12px rgba(196, 14, 37, 0.3),
              inset 0 1px 0 rgba(255, 255, 255, 0.2);
  z-index: 9999 !important;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  opacity: 1 !important;
  visibility: visible !important;
  transform: translateY(0) scale(1) !important;
  margin: 0 !important;
  padding: 0 !important;
  position: relative;
  overflow: hidden;
}

.ai-chat-fab::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, 
    rgba(255, 255, 255, 0.3) 0%, 
    transparent 70%);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.ai-chat-fab:hover::before {
  opacity: 1;
}

.ai-chat-fab:hover {
  transform: translateY(-4px) scale(1.08);
  box-shadow: 0 12px 32px rgba(196, 14, 37, 0.5),
              0 6px 16px rgba(196, 14, 37, 0.4),
              inset 0 1px 0 rgba(255, 255, 255, 0.3);
  border-color: rgba(255, 255, 255, 0.5);
}

.ai-chat-fab:active {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 6px 16px rgba(196, 14, 37, 0.4),
              0 3px 8px rgba(196, 14, 37, 0.3);
}

/* 添加脉冲动画效果 */
@keyframes aiChatPulse {
  0%, 100% {
    box-shadow: 0 8px 24px rgba(196, 14, 37, 0.4),
                0 4px 12px rgba(196, 14, 37, 0.3),
                0 0 0 0 rgba(196, 14, 37, 0.7);
  }
  50% {
    box-shadow: 0 8px 24px rgba(196, 14, 37, 0.4),
                0 4px 12px rgba(196, 14, 37, 0.3),
                0 0 0 8px rgba(196, 14, 37, 0);
  }
}

.ai-chat-fab {
  animation: aiChatPulse 2s ease-in-out infinite;
}

.ai-chat-fab svg {
  transition: transform 0.3s ease;
  width: 26px;
  height: 26px;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
  position: relative;
  z-index: 1;
}

.ai-chat-fab:hover svg {
  transform: scale(1.1) rotate(5deg);
}

/* 当对话窗口打开时隐藏FAB按钮 */
body.ai-chat-open .ai-chat-fab,
.ai-chat-widget[data-open="true"] ~ .ai-chat-fab {
  opacity: 0 !important;
  visibility: hidden !important;
  pointer-events: none !important;
  transform: translateY(20px) scale(0.9) !important;
  display: none !important;
}

/* AI对话窗口 */
.ai-chat-widget {
  position: fixed;
  top: 0;
  right: 0;
  width: 420px;
  height: 100vh;
  background: #ffffff;
  box-shadow: -4px 0 24px rgba(0, 0, 0, 0.15);
  display: flex;
  flex-direction: column;
  z-index: 1000;
  transform: translateX(100%);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  border-left: 1px solid rgba(196, 14, 37, 0.1);
  overflow: hidden;
}

.ai-chat-widget[data-open="true"] {
  transform: translateX(0);
}

.ai-chat-header {
  background: linear-gradient(135deg, var(--brand-red), var(--brand-dark));
  color: #ffffff;
  padding: 1.25rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.ai-chat-header-content {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.ai-chat-header h3 {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 600;
}

.ai-chat-header p {
  margin: 0;
  font-size: 0.85rem;
  opacity: 0.9;
  color: rgba(255, 255, 255, 0.9);
}

.ai-chat-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  flex-shrink: 0;
  border: 2px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  transition: all 0.3s ease;
}

.ai-chat-avatar:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.ai-chat-avatar svg {
  animation: aiPulse 2s ease-in-out infinite;
}

@keyframes aiPulse {
  0%, 100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.9;
    transform: scale(0.98);
  }
}

.ai-chat-close {
  background: transparent;
  border: none;
  color: #ffffff;
  font-size: 1.8rem;
  line-height: 1;
  cursor: pointer;
  padding: 0.25rem;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.ai-chat-close:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: rotate(90deg);
}

.ai-chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: #fafafa;
  min-height: 0;
}

.ai-chat-message {
  display: flex;
  gap: 0.75rem;
  animation: messageSlideIn 0.3s ease;
}

@keyframes messageSlideIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.ai-chat-message.user-message {
  flex-direction: row-reverse;
}

.ai-chat-message .ai-chat-avatar {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, var(--brand-light), #fff5f5);
  color: var(--brand-red);
  flex-shrink: 0;
  border: 1.5px solid rgba(196, 14, 37, 0.2);
  box-shadow: 0 2px 6px rgba(196, 14, 37, 0.1);
  transition: all 0.3s ease;
}

.ai-chat-message .ai-chat-avatar:hover {
  transform: scale(1.08);
  box-shadow: 0 3px 8px rgba(196, 14, 37, 0.15);
}

.ai-chat-message .ai-chat-avatar svg {
  animation: aiPulse 2s ease-in-out infinite;
}

.user-message .ai-chat-avatar {
  background: var(--brand-red);
  color: #ffffff;
}

.ai-chat-bubble {
  max-width: 75%;
  padding: 0.75rem 1rem;
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  position: relative;
}

.ai-message .ai-chat-bubble {
  background: #ffffff;
  border: 1px solid rgba(196, 14, 37, 0.1);
}

.user-message .ai-chat-bubble {
  background: linear-gradient(135deg, var(--brand-red), var(--brand-dark));
  color: #ffffff;
}

.ai-chat-bubble p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.5;
  word-wrap: break-word;
}

.user-message .ai-chat-bubble p {
  color: #ffffff;
}

.ai-chat-input-container {
  padding: 1rem 1.5rem;
  background: #ffffff;
  border-top: 1px solid rgba(196, 14, 37, 0.1);
}

.ai-chat-form {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.ai-chat-input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-light);
  border-radius: 20px;
  font-size: 0.9rem;
  transition: all 0.2s ease;
}

.ai-chat-input:focus {
  outline: none;
  border-color: var(--brand-red);
  box-shadow: 0 0 0 3px rgba(196, 14, 37, 0.1);
}

.ai-chat-send {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-red), var(--brand-dark));
  color: #ffffff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.ai-chat-send:hover:not(:disabled) {
  transform: scale(1.1);
  box-shadow: 0 4px 12px rgba(196, 14, 37, 0.3);
}

.ai-chat-send:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.ai-chat-status {
  margin-top: 0.5rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  text-align: center;
  min-height: 1rem;
}

.ai-chat-status.error {
  color: #b00020;
}

.ai-chat-status.loading {
  color: var(--brand-red);
}

.ai-chat-status.loading::after {
  content: '...';
  animation: dots 1.5s steps(4, end) infinite;
}

@keyframes dots {
  0%, 20% { content: '.'; }
  40% { content: '..'; }
  60%, 100% { content: '...'; }
}

@media (max-width: 768px) {
  .ai-chat-fab {
    bottom: 24px;
    right: 24px;
    width: 52px;
    height: 52px;
  }
  
  .ai-chat-fab svg {
    width: 22px;
    height: 22px;
  }
  
  .ai-chat-widget {
    width: 100%;
    height: 50vh;
    top: auto;
    bottom: 0;
    border-radius: 24px 24px 0 0;
    border-left: none;
    border-top: 1px solid rgba(196, 14, 37, 0.1);
    transform: translateY(100%);
  }
  
  .ai-chat-widget[data-open="true"] {
    transform: translateY(0);
  }
  
  .ai-chat-messages {
    max-height: calc(50vh - 180px);
  }
}

@media (max-width: 480px) {
  .ai-chat-fab {
    bottom: 20px;
    right: 20px;
    width: 52px;
    height: 52px;
    border-width: 2px;
  }
  
  .ai-chat-fab svg {
    width: 22px;
    height: 22px;
  }
  
  .ai-chat-widget {
    border-radius: 20px 20px 0 0;
  }
  
  .ai-chat-header {
    padding: 1rem;
  }
  
  .ai-chat-messages {
    padding: 1rem;
    max-height: calc(50vh - 160px);
  }
  
  .ai-chat-input-container {
    padding: 0.75rem 1rem;
  }
}