/* =====================================================
   蚂蚁加速器 - 主样式表
   配色: 深绿暗色系 #0b1f17 / #0d2a1f / #1a3a2a
   主色: #39ff14 (亮绿) / #00c853 (中绿)
   ===================================================== */

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

:root {
  --bg-base:      #0b1f17;
  --bg-card:      #0f2820;
  --bg-card-alt:  #122e23;
  --bg-header:    rgba(11, 31, 23, 0.95);
  --color-primary: #39ff14;
  --color-mid:    #00c853;
  --color-text:   #e8f5e9;
  --color-muted:  #7dab8a;
  --color-border: rgba(57, 255, 20, 0.12);
  --color-pain:   #ff5252;
  --color-solve:  #69f0ae;
  --radius-sm:    8px;
  --radius-md:    14px;
  --radius-lg:    20px;
  --shadow-card:  0 4px 24px rgba(0,0,0,0.4);
  --font-main:    'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --transition:   0.25s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-main);
  background-color: var(--bg-base);
  color: var(--color-text);
  line-height: 1.6;
  font-size: 15px;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
ul, ol { padding-left: 1.4em; }

/* ---------- 通用区块布局 ---------- */
.section-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

section {
  padding: 90px 0;
}

.section-label {
  display: inline-block;
  background: rgba(57, 255, 20, 0.12);
  color: var(--color-primary);
  border: 1px solid rgba(57, 255, 20, 0.3);
  padding: 4px 14px;
  border-radius: 50px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-bottom: 18px;
}

.section-title {
  font-size: clamp(24px, 3.5vw, 38px);
  font-weight: 700;
  color: #fff;
  margin-bottom: 14px;
  line-height: 1.25;
  text-align: center;
}

.section-subtitle {
  font-size: 16px;
  color: var(--color-muted);
  max-width: 620px;
  margin: 0 auto 50px;
  text-align: center;
  line-height: 1.7;
}

/* =====================================================
   HEADER
   ===================================================== */
#site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: transparent;
  transition: background var(--transition), backdrop-filter var(--transition), border-bottom var(--transition);
  border-bottom: 1px solid transparent;
}

#site-header.scrolled {
  background: var(--bg-header);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 32px;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, #39ff14, #00c853);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  box-shadow: 0 0 16px rgba(57,255,20,0.35);
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.brand-name {
  font-size: 16px;
  font-weight: 700;
  color: #fff;
}

.brand-sub {
  font-size: 10px;
  color: var(--color-primary);
  font-weight: 600;
  letter-spacing: 0.08em;
}

/* Nav */
#mainNav {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  flex-wrap: nowrap;
}

#mainNav a {
  color: var(--color-muted);
  font-size: 14px;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
  white-space: nowrap;
}

#mainNav a:hover {
  color: var(--color-text);
  background: rgba(255,255,255,0.06);
}

/* CTA download button in nav */
.nav-cta {
  background: linear-gradient(135deg, #39ff14, #00c853) !important;
  color: #0b1f17 !important;
  font-weight: 700 !important;
  padding: 8px 18px !important;
  border-radius: 50px !important;
  font-size: 14px !important;
  transition: opacity var(--transition), transform var(--transition) !important;
  box-shadow: 0 0 14px rgba(57,255,20,0.3);
}

.nav-cta:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

/* Hamburger */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  margin-left: auto;
  border-radius: var(--radius-sm);
}

.menu-toggle span {
  display: block;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.menu-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* =====================================================
   HERO
   ===================================================== */
#hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 64px;
  background:
    radial-gradient(ellipse 60% 55% at 70% 50%, rgba(57,255,20,0.07) 0%, transparent 70%),
    radial-gradient(ellipse 40% 40% at 10% 80%, rgba(0,200,83,0.05) 0%, transparent 60%),
    var(--bg-base);
}

#hero .section-container {
  display: flex;
  align-items: center;
  gap: 60px;
  padding-top: 40px;
  padding-bottom: 40px;
  width: 100%;
}

.hero-content { flex: 1; max-width: 600px; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(57,255,20,0.1);
  border: 1px solid rgba(57,255,20,0.25);
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 50px;
  margin-bottom: 24px;
}

.hero-badge .dot {
  width: 7px;
  height: 7px;
  background: var(--color-primary);
  border-radius: 50%;
  animation: pulse-dot 2s infinite;
  flex-shrink: 0;
}

@keyframes pulse-dot {
  0%, 100% { box-shadow: 0 0 0 0 rgba(57,255,20,0.6); }
  50%       { box-shadow: 0 0 0 5px rgba(57,255,20,0); }
}

#hero h1 {
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 800;
  color: #fff;
  line-height: 1.15;
  margin-bottom: 22px;
}

#hero h1 .highlight {
  color: var(--color-primary);
  text-shadow: 0 0 20px rgba(57,255,20,0.4);
}

.hero-desc {
  font-size: 16px;
  color: var(--color-muted);
  line-height: 1.75;
  margin-bottom: 28px;
}

.hero-desc strong { color: var(--color-text); font-weight: 600; }

.hero-rating {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 32px;
  font-size: 14px;
}

.stars { font-size: 18px; letter-spacing: 2px; }
.rating-text { font-weight: 700; color: #fff; font-size: 16px; }
.rating-count { color: var(--color-muted); }

.hero-buttons {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 50px;
  font-weight: 700;
  font-size: 15px;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
}

.btn:hover { transform: translateY(-2px); }

.btn-primary {
  background: linear-gradient(135deg, #39ff14, #00c853);
  color: #0b1f17;
  box-shadow: 0 4px 20px rgba(57,255,20,0.35);
}

.btn-primary:hover { box-shadow: 0 6px 28px rgba(57,255,20,0.5); }

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border: 1px solid rgba(255,255,255,0.2);
}

.btn-secondary:hover { border-color: rgba(255,255,255,0.4); background: rgba(255,255,255,0.05); }

.btn-icon { width: 18px; height: 18px; flex-shrink: 0; }

/* Hero visual */
.hero-visual {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-visual-inner {
  width: 280px;
  height: 280px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(57,255,20,0.12) 0%, rgba(0,200,83,0.05) 50%, transparent 70%);
  border: 1px solid rgba(57,255,20,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 100px;
  position: relative;
  animation: float-shield 5s ease-in-out infinite;
}

.hero-visual-inner::before {
  content: '';
  position: absolute;
  inset: -16px;
  border-radius: 50%;
  border: 1px solid rgba(57,255,20,0.1);
  animation: float-shield 5s ease-in-out infinite reverse;
}

@keyframes float-shield {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-14px); }
}

/* =====================================================
   FEATURES (核心优势)
   ===================================================== */
#features { background: var(--bg-card); }

#features .section-title,
#features .section-label { text-align: center; display: block; }

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 22px;
}

.feature-card {
  background: var(--bg-card-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: border-color var(--transition), transform var(--transition);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.feature-card:hover {
  border-color: rgba(57,255,20,0.3);
  transform: translateY(-4px);
}

.feature-icon { font-size: 38px; }

.pain-point {
  font-size: 13px;
  color: var(--color-pain);
  font-weight: 600;
}

.solution {
  font-size: 13px;
  color: var(--color-solve);
  font-weight: 600;
}

.feature-card p {
  font-size: 14px;
  color: var(--color-muted);
  line-height: 1.65;
  margin-top: 4px;
}

/* =====================================================
   USE CASES (适用场景)
   ===================================================== */
#usecases .section-title,
#usecases .section-label { text-align: center; display: block; }

.usecases-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.usecase-card {
  background: var(--bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 30px 20px 24px;
  text-align: center;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.usecase-card:hover {
  border-color: rgba(57,255,20,0.35);
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.3);
}

.usecase-icon { font-size: 40px; display: block; margin-bottom: 14px; }

.usecase-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 10px;
}

.usecase-card p {
  font-size: 13.5px;
  color: var(--color-muted);
  line-height: 1.65;
}

/* =====================================================
   HIGHLIGHTS (功能亮点)
   ===================================================== */
#highlights { background: var(--bg-card); }

#highlights .section-title,
#highlights .section-label { text-align: center; display: block; }

.highlights-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 22px;
}

.highlight-card {
  background: var(--bg-card-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  position: relative;
  transition: border-color var(--transition), transform var(--transition);
}

.highlight-card:hover {
  border-color: rgba(57,255,20,0.3);
  transform: translateY(-4px);
}

.highlight-tag {
  display: inline-block;
  background: rgba(57,255,20,0.1);
  color: var(--color-primary);
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 50px;
  margin-bottom: 14px;
  letter-spacing: 0.06em;
}

.hl-icon {
  font-size: 34px;
  display: block;
  margin-bottom: 12px;
}

.highlight-card h3 {
  font-size: 17px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 10px;
}

.highlight-card p {
  font-size: 14px;
  color: var(--color-muted);
  line-height: 1.65;
}

/* =====================================================
   TESTIMONIALS (用户评价)
   ===================================================== */
#testimonials .section-title,
#testimonials .section-label { text-align: center; display: block; }

.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px 26px 24px;
  position: relative;
  transition: border-color var(--transition), transform var(--transition);
}

.testimonial-card:hover {
  border-color: rgba(57,255,20,0.25);
  transform: translateY(-3px);
}

.quote-mark {
  font-size: 56px;
  line-height: 1;
  color: var(--color-primary);
  opacity: 0.6;
  font-family: Georgia, serif;
  position: absolute;
  top: 12px;
  left: 22px;
}

.t-stars { font-size: 16px; margin-bottom: 12px; padding-top: 24px; }

.t-text {
  font-size: 14px;
  color: var(--color-muted);
  line-height: 1.75;
  margin-bottom: 20px;
}

.t-text strong { color: var(--color-text); }

.t-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.t-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 16px;
  flex-shrink: 0;
  color: #fff;
}

.av1 { background: linear-gradient(135deg, #e53935, #b71c1c); }
.av2 { background: linear-gradient(135deg, #1976d2, #0d47a1); }
.av3 { background: linear-gradient(135deg, #f57c00, #e65100); }

.t-name {
  display: block;
  font-weight: 700;
  color: #fff;
  font-size: 14px;
}

.t-role {
  display: block;
  font-size: 12px;
  color: var(--color-muted);
}

/* =====================================================
   NEWS (新闻资讯)
   ===================================================== */
#news { background: var(--bg-card); }

#news .section-title,
#news .section-label { text-align: center; display: block; }

.news-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 22px;
}

.news-card {
  background: var(--bg-card-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition), transform var(--transition);
}

.news-card:hover {
  border-color: rgba(57,255,20,0.3);
  transform: translateY(-4px);
}

.news-img-placeholder {
  height: 130px;
  background: linear-gradient(135deg, rgba(57,255,20,0.06) 0%, rgba(0,200,83,0.1) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 52px;
  border-bottom: 1px solid var(--color-border);
}

.news-body {
  padding: 20px 20px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.news-date {
  font-size: 12px;
  color: var(--color-muted);
}

.news-card h3 {
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  line-height: 1.45;
}

.news-excerpt {
  font-size: 13px;
  color: var(--color-muted);
  line-height: 1.65;
}

.news-link {
  font-size: 13px;
  color: var(--color-primary);
  font-weight: 600;
  cursor: default;
}

/* =====================================================
   FAQ (常见问题)
   ===================================================== */
#faq .section-title,
#faq .section-label { text-align: center; display: block; }

.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition);
}

.faq-item:hover { border-color: rgba(57,255,20,0.3); }

.faq-item details { width: 100%; }

.faq-item summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  color: var(--color-text);
  list-style: none;
  gap: 12px;
  user-select: none;
  transition: color var(--transition);
}

.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary:hover { color: #fff; }

.faq-arrow {
  color: var(--color-primary);
  font-size: 11px;
  transition: transform var(--transition);
  flex-shrink: 0;
}

.faq-item details[open] .faq-arrow { transform: rotate(180deg); }
.faq-item details[open] summary { color: #fff; border-bottom: 1px solid var(--color-border); }

.faq-content-wrapper { padding: 22px 24px 24px; }

.faq-content-inner ol {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-content-inner li {
  font-size: 14px;
  line-height: 1.7;
}

.faq-content-inner li strong {
  display: block;
  color: var(--color-primary);
  margin-bottom: 4px;
  font-size: 14px;
}

.step-detail {
  display: block;
  color: var(--color-muted);
  font-size: 13.5px;
  line-height: 1.75;
}

/* =====================================================
   CTA SECTION
   ===================================================== */
#cta-section {
  background: linear-gradient(135deg, rgba(57,255,20,0.08) 0%, rgba(0,200,83,0.05) 100%);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  text-align: center;
  padding: 80px 0;
}

#cta-section .section-container { display: block; }

.cta-title {
  font-size: clamp(26px, 4vw, 44px);
  font-weight: 800;
  color: #fff;
  margin-bottom: 14px;
}

.cta-title span { color: var(--color-primary); }

.cta-sub {
  font-size: 16px;
  color: var(--color-muted);
  margin-bottom: 36px;
}

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

/* =====================================================
   FOOTER
   ===================================================== */
footer {
  background: #080f0b;
  padding: 48px 0 32px;
  border-top: 1px solid rgba(57,255,20,0.08);
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.footer-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
}

.footer-brand .brand-name { font-size: 18px; font-weight: 700; color: #fff; display: block; }
.footer-brand p { font-size: 13px; color: var(--color-muted); max-width: 260px; margin-top: 8px; line-height: 1.6; }

.footer-links {
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 700;
  color: #fff;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-bottom: 14px;
}

.footer-col ul { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 8px; }

.footer-col a {
  font-size: 13px;
  color: var(--color-muted);
  transition: color var(--transition);
}

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

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.06);
  padding-top: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-copy {
  font-size: 12px;
  color: var(--color-muted);
}

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

.badge {
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 50px;
  background: rgba(57,255,20,0.08);
  color: var(--color-primary);
  border: 1px solid rgba(57,255,20,0.2);
}

/* =====================================================
   BACK TO TOP
   ===================================================== */
#back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 900;
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, #39ff14, #00c853);
  color: #0b1f17;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  font-size: 18px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity var(--transition), transform var(--transition);
  box-shadow: 0 4px 16px rgba(57,255,20,0.35);
}

#back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

#back-to-top:hover { transform: translateY(-2px); }

/* =====================================================
   RESPONSIVE
   ===================================================== */
@media (max-width: 900px) {
  #hero .section-container { flex-direction: column; text-align: center; }
  .hero-content { max-width: 100%; }
  .hero-buttons { justify-content: center; }
  .hero-rating { justify-content: center; }
  .hero-visual-inner { width: 220px; height: 220px; font-size: 80px; }
  .footer-top { flex-direction: column; }
}

@media (max-width: 768px) {
  section { padding: 64px 0; }

  .menu-toggle { display: flex; }

  #mainNav {
    position: fixed;
    top: 64px; left: 0; right: 0;
    background: var(--bg-header);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    flex-direction: column;
    padding: 20px 24px 28px;
    gap: 4px;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-110%);
    transition: transform 0.3s ease;
    margin-left: 0;
  }

  #mainNav.open { transform: translateY(0); }

  #mainNav a {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    border-radius: var(--radius-sm);
  }

  .nav-cta {
    margin-top: 8px;
    text-align: center;
    padding: 12px 16px !important;
  }

  .features-grid { grid-template-columns: 1fr; }
  .usecases-grid { grid-template-columns: 1fr 1fr; }
  .news-grid { grid-template-columns: 1fr; }
  .highlights-grid { grid-template-columns: 1fr; }
  .testimonials-grid { grid-template-columns: 1fr; }
  .footer-links { gap: 28px; }
}

@media (max-width: 480px) {
  .usecases-grid { grid-template-columns: 1fr; }
  .hero-visual { display: none; }
  .cta-buttons { flex-direction: column; align-items: center; }
}