:root {
  --primary-purple: #7928ca;
  --primary-light: #9d4edd;
  --primary-dark: #5a189a;
  --accent-pink: #ff007f;
  --accent-cyan: #00f2fe;
  --bg-main: #fcfbfe;
  --bg-sub: #f5f0fb;
  --text-main: #1f1d2b;
  --text-sub: #4b4860;
  --text-muted: #6e6a88;
  --card-bg: #ffffff;
  --card-border: #ede4f8;
  --card-shadow: 0 10px 30px rgba(121, 40, 202, 0.07);
  --card-shadow-hover: 0 16px 40px rgba(121, 40, 202, 0.15);
  --btn-gradient: linear-gradient(135deg, #7928ca 0%, #ff007f 100%);
  --btn-gradient-hover: linear-gradient(135deg, #8b38df 0%, #ff2a93 100%);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

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

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text-main);
  background-color: var(--bg-main);
  background-image: radial-gradient(#e9d5ff 1px, transparent 1px), radial-gradient(#ede9fe 1px, #fcfbfe 1px);
  background-size: 40px 40px;
  background-position: 0 0, 20px 20px;
  font-size: 16px;
  line-height: 1.6;
}

body {
  overflow-x: hidden;
}

.ai-container {
  width: 100%;
  max-width: 1240px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* Header & Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(121, 40, 202, 0.1);
  transition: all 0.3s ease;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.brand-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-area .ai-page-logo {
  max-height: 42px;
  width: auto;
  display: block;
}

.brand-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--primary-dark);
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 0;
}

.nav-links li a {
  display: inline-block;
  padding: 8px 14px;
  color: var(--text-sub);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.25s ease;
  border-radius: var(--radius-sm);
}

.nav-links li a:hover,
.nav-links li a.active {
  color: var(--primary-purple);
  background-color: rgba(121, 40, 202, 0.05);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  background: var(--btn-gradient);
  color: #ffffff !important;
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 50px;
  text-decoration: none;
  box-shadow: 0 4px 15px rgba(121, 40, 202, 0.3);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  border: none;
  cursor: pointer;
}

.btn-primary:hover {
  background: var(--btn-gradient-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(121, 40, 202, 0.4);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 20px;
  background: #ffffff;
  color: var(--primary-purple) !important;
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: 50px;
  text-decoration: none;
  border: 1.5px solid var(--primary-purple);
  transition: all 0.25s ease;
}

.btn-outline:hover {
  background: var(--primary-purple);
  color: #ffffff !important;
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.6rem;
  color: var(--primary-dark);
  cursor: pointer;
}

/* Hero Section (No Images Allowed) */
.hero-section {
  padding: 70px 0 60px 0;
  background: linear-gradient(180deg, rgba(245, 240, 251, 0.6) 0%, rgba(252, 251, 254, 0) 100%);
  position: relative;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  padding: 6px 18px;
  background: #f0e6ff;
  border: 1px solid #d8b4fe;
  border-radius: 50px;
  color: var(--primary-dark);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-badge::before {
  content: "✨";
  margin-right: 6px;
}

.hero-title {
  font-size: 2.8rem;
  font-weight: 900;
  line-height: 1.25;
  color: var(--text-main);
  margin-bottom: 20px;
  letter-spacing: -1px;
}

.hero-title span {
  background: var(--btn-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.18rem;
  color: var(--text-sub);
  max-width: 820px;
  margin: 0 auto 36px auto;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

.hero-cta-group .btn-hero-main {
  padding: 15px 36px;
  font-size: 1.1rem;
}

.hero-highlights {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  margin-top: 20px;
}

.highlight-box {
  background: #ffffff;
  padding: 22px 18px;
  border-radius: var(--radius-md);
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
  text-align: center;
  transition: transform 0.3s ease;
}

.highlight-box:hover {
  transform: translateY(-4px);
}

.highlight-num {
  font-size: 1.9rem;
  font-weight: 800;
  color: var(--primary-purple);
  margin-bottom: 4px;
}

.highlight-label {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* Common Section Layout */
.section-wrapper {
  padding: 75px 0;
}

.section-head {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 48px auto;
}

.section-tag {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--primary-purple);
  background: rgba(121, 40, 202, 0.08);
  padding: 4px 14px;
  border-radius: 30px;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 14px;
  line-height: 1.3;
}

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

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

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

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
}

.custom-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 26px;
  box-shadow: var(--card-shadow);
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
}

.custom-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--card-shadow-hover);
  border-color: #d8b4fe;
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: linear-gradient(135deg, rgba(121, 40, 202, 0.1), rgba(255, 0, 127, 0.1));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--primary-purple);
  margin-bottom: 18px;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
}

.card-text {
  font-size: 0.93rem;
  color: var(--text-sub);
  line-height: 1.6;
  flex-grow: 1;
}

.card-badge {
  display: inline-block;
  padding: 3px 10px;
  background: #f3e8ff;
  color: var(--primary-dark);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 4px;
  margin-top: 14px;
  align-self: flex-start;
}

/* Models Tag Cloud */
.model-tags-container {
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--card-shadow);
  margin-top: 36px;
}

.model-tags-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 16px;
  text-align: center;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.tag-item {
  background: #faf5ff;
  border: 1px solid #e9d5ff;
  color: var(--primary-dark);
  padding: 6px 14px;
  border-radius: 30px;
  font-size: 0.85rem;
  font-weight: 600;
  transition: all 0.2s ease;
}

.tag-item:hover {
  background: var(--primary-purple);
  color: #ffffff;
  border-color: var(--primary-purple);
}

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

.step-card {
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  position: relative;
  box-shadow: var(--card-shadow);
}

.step-number {
  font-size: 2.2rem;
  font-weight: 900;
  color: rgba(121, 40, 202, 0.15);
  line-height: 1;
  margin-bottom: 8px;
}

.step-name {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 8px;
}

.step-desc {
  font-size: 0.88rem;
  color: var(--text-sub);
}

/* Comparison Table */
.comparison-container {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
  overflow-x: auto;
  padding: 10px;
}

.comparison-header-score {
  background: linear-gradient(135deg, #fbf7ff 0%, #f3e8ff 100%);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  border: 1px solid #e9d5ff;
}

.score-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-main);
}

.score-badge {
  display: flex;
  align-items: center;
  gap: 12px;
}

.stars {
  color: #ffaa00;
  font-size: 1.4rem;
  letter-spacing: 2px;
}

.score-num {
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--primary-purple);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.comparison-table th,
.comparison-table td {
  padding: 16px 20px;
  border-bottom: 1px solid #f0eaf8;
  font-size: 0.95rem;
}

.comparison-table th {
  background: #faf8fd;
  color: var(--text-main);
  font-weight: 700;
}

.comparison-table td strong {
  color: var(--text-main);
}

.highlight-row {
  background: rgba(121, 40, 202, 0.03);
  font-weight: 600;
}

.highlight-row td:nth-child(2) {
  color: var(--primary-purple);
  font-weight: 700;
}

/* Media Showcase */
.media-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.media-item {
  background: #ffffff;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
}

.media-img-wrap {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #f3f0f7;
  overflow: hidden;
}

.media-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media-content {
  padding: 20px;
}

.media-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 6px;
}

.media-desc {
  font-size: 0.88rem;
  color: var(--text-sub);
}

/* Reviews Grid */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.review-card {
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-text {
  font-size: 0.93rem;
  color: var(--text-sub);
  line-height: 1.6;
  margin-bottom: 18px;
  font-style: normal;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid #f0eaf8;
  padding-top: 14px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-purple), var(--accent-pink));
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.05rem;
}

.author-meta h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.author-meta p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* FAQ Accordion */
.faq-list {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: border-color 0.2s ease;
}

.faq-question {
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--text-main);
  cursor: pointer;
  background: #ffffff;
  user-select: none;
}

.faq-icon {
  font-size: 1.2rem;
  color: var(--primary-purple);
  transition: transform 0.3s ease;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  background: #faf8fd;
}

.faq-answer-inner {
  padding: 0 22px 18px 22px;
  font-size: 0.92rem;
  color: var(--text-sub);
  line-height: 1.6;
}

.faq-item.active {
  border-color: #d8b4fe;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-item.active .faq-answer {
  max-height: 250px;
}

/* Articles & Knowledge */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.article-card {
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 22px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.article-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
}

.article-card p {
  font-size: 0.88rem;
  color: var(--text-sub);
  margin-bottom: 16px;
  flex-grow: 1;
}

.article-link {
  color: var(--primary-purple);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.article-link:hover {
  text-decoration: underline;
}

/* Contact & Form */
.contact-container {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 36px;
  background: #ffffff;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--card-shadow);
}

.contact-info h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 16px;
}

.contact-info p {
  font-size: 0.95rem;
  color: var(--text-sub);
  margin-bottom: 24px;
}

.contact-items {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 28px;
}

.contact-item-row {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.95rem;
  color: var(--text-main);
}

.contact-item-row strong {
  color: var(--primary-dark);
}

.qrcode-box {
  display: inline-block;
  padding: 12px;
  background: #faf5ff;
  border: 1px solid #e9d5ff;
  border-radius: var(--radius-md);
  text-align: center;
}

.qrcode-box img {
  width: 130px;
  height: 130px;
  object-fit: contain;
  border-radius: var(--radius-sm);
  display: block;
  margin: 0 auto 8px auto;
}

.qrcode-box span {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 600;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid #d8cde6;
  border-radius: var(--radius-sm);
  font-size: 0.92rem;
  color: var(--text-main);
  background: #faf8fc;
  outline: none;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.form-control:focus {
  border-color: var(--primary-purple);
  background: #ffffff;
}

textarea.form-control {
  resize: vertical;
  min-height: 95px;
}

/* Footer */
.site-footer {
  background: #181524;
  color: #c9c5d8;
  padding: 55px 0 25px 0;
  margin-top: 40px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 30px;
  padding-bottom: 35px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand h4 {
  font-size: 1.3rem;
  color: #ffffff;
  font-weight: 800;
  margin-bottom: 12px;
}

.footer-brand p {
  font-size: 0.88rem;
  line-height: 1.6;
  color: #a5a0b8;
  max-width: 320px;
}

.footer-col h5 {
  font-size: 1rem;
  color: #ffffff;
  font-weight: 700;
  margin-bottom: 14px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-col ul li a {
  color: #a5a0b8;
  text-decoration: none;
  font-size: 0.88rem;
  transition: color 0.2s ease;
}

.footer-col ul li a:hover {
  color: #ffffff;
}

.footer-links-row {
  padding: 22px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.85rem;
}

.footer-links-row strong {
  color: #ffffff;
  margin-right: 12px;
}

.footer-links-row a {
  color: #a5a0b8;
  text-decoration: none;
  margin-right: 14px;
  display: inline-block;
  transition: color 0.2s ease;
}

.footer-links-row a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: #7d7894;
}

/* Floating Actions */
.floating-widget {
  position: fixed;
  right: 20px;
  bottom: 30px;
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.float-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--btn-gradient);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 15px rgba(121, 40, 202, 0.35);
  cursor: pointer;
  text-decoration: none;
  font-size: 1.2rem;
  transition: transform 0.2s ease;
  border: none;
}

.float-btn:hover {
  transform: scale(1.08);
}

/* Responsive */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.2rem;
  }
  .grid-4, .process-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-highlights {
    grid-template-columns: repeat(2, 1fr);
  }
  .grid-3, .reviews-grid, .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .contact-container {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .mobile-toggle {
    display: block;
  }
  .nav-links {
    display: none;
    position: absolute;
    top: 76px;
    left: 0;
    width: 100%;
    background: #ffffff;
    flex-direction: column;
    padding: 20px;
    border-bottom: 1px solid #e9d5ff;
    box-shadow: 0 10px 20px rgba(0,0,0,0.05);
  }
  .nav-links.show {
    display: flex;
  }
  .nav-actions {
    display: none;
  }
  .hero-title {
    font-size: 1.8rem;
  }
  .hero-subtitle {
    font-size: 1rem;
  }
  .grid-3, .grid-2, .reviews-grid, .article-grid, .media-grid {
    grid-template-columns: 1fr;
  }
  .hero-highlights, .grid-4, .process-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }
}