/* ============================================
   凌云科技 · 特殊人群志愿服务社 —— 官网样式
   ============================================ */

:root {
  --primary: #16a34a;
  --primary-dark: #15803d;
  --primary-deep: #166534;
  --accent: #fbbf24;
  --accent-dark: #d97706;
  --ink: #1f2937;
  --text: #475569;
  --text-light: #64748b;
  --bg: #ffffff;
  --bg-soft: #f6faf7;
  --bg-blue: #ecfdf5;
  --border: #e5eaf1;
  --shadow-sm: 0 4px 12px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 12px 30px rgba(15, 23, 42, 0.10);
  --shadow-lg: 0 24px 60px rgba(15, 23, 42, 0.14);
  --radius: 16px;
  --radius-lg: 24px;
  --font: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

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

.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============ 按钮 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 8px 20px rgba(22, 163, 74, 0.30);
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 12px 26px rgba(22, 163, 74, 0.38);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.10);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.35);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.22);
  transform: translateY(-2px);
}

.btn-light {
  background: #fff;
  color: var(--primary-deep);
}

.btn-light:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 26px rgba(0, 0, 0, 0.18);
}

.btn-block {
  width: 100%;
}

/* ============ 顶部导航 ============ */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  padding: 18px 0;
  transition: padding 0.3s ease, background 0.3s ease, box-shadow 0.3s ease;
  background: transparent;
}

.header.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  padding: 12px 0;
  box-shadow: 0 4px 20px rgba(15, 23, 42, 0.08);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.logo-mark {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--primary), var(--primary-deep));
  color: #fff;
  font-size: 20px;
  font-weight: 700;
  display: grid;
  place-items: center;
  box-shadow: 0 6px 16px rgba(22, 163, 74, 0.35);
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.logo-text strong {
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 1px;
}

.logo-text em {
  font-style: normal;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.75);
  letter-spacing: 2px;
}

.header.scrolled .logo-text strong {
  color: var(--ink);
}

.header.scrolled .logo-text em {
  color: var(--text-light);
}

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

.nav-link {
  position: relative;
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.88);
  transition: color 0.2s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 0;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  transition: width 0.25s ease;
}

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

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

.header.scrolled .nav-link {
  color: var(--text);
}

.header.scrolled .nav-link:hover,
.header.scrolled .nav-link.active {
  color: var(--primary);
}

.nav-cta {
  padding: 10px 22px;
  font-size: 14px;
}

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

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

.header.scrolled .nav-toggle span {
  background: var(--ink);
}

/* ============ Hero ============ */
.hero {
  position: relative;
  padding: 170px 0 240px;
  background:
    linear-gradient(180deg, transparent 0 75%, #ffffff 75%),
    linear-gradient(135deg, #052e16 0%, #15803d 45%, #16a34a 100%);
  color: #fff;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.12) 0, transparent 40%),
    radial-gradient(circle at 10% 80%, rgba(251, 191, 36, 0.22) 0, transparent 45%);
}

.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(circle at 50% 40%, #000, transparent 75%);
}

.scroll-hint {
  position: absolute;
  left: 50%;
  bottom: 30px;
  transform: translateX(-50%);
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  color: var(--primary);
  font-size: 13px;
  letter-spacing: 2px;
  animation: scroll-float 2s ease-in-out infinite;
}

.scroll-hint svg {
  fill: var(--primary);
}

@keyframes scroll-float {
  0%, 100% { transform: translate(-50%, 0); }
  50% { transform: translate(-50%, 8px); }
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-tag {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.25);
  font-size: 13px;
  letter-spacing: 2px;
  margin-bottom: 22px;
}

.hero-content h1 {
  font-size: 48px;
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: 1px;
}

.text-accent {
  color: var(--accent);
}

.hero-desc {
  margin: 24px 0 34px;
  font-size: 17px;
  color: rgba(255, 255, 255, 0.85);
  max-width: 520px;
}

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

/* 右侧卡片面板 */
.hero-panel {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.panel-card {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
  padding: 24px;
  backdrop-filter: blur(6px);
  transition: transform 0.25s ease, background 0.25s ease;
}

.panel-card:hover {
  transform: translateY(-6px);
  background: rgba(255, 255, 255, 0.14);
}

.panel-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.14);
  display: grid;
  place-items: center;
  margin-bottom: 16px;
}

.panel-icon svg {
  fill: #fff;
}

.panel-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.panel-card p {
  font-size: 13.5px;
  color: rgba(255, 255, 255, 0.78);
  line-height: 1.6;
}

/* ============ 统计 ============ */
.stats {
  background: #fff;
  padding: 56px 0;
  border-bottom: 1px solid var(--border);
}

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

.stat-num {
  font-size: 42px;
  font-weight: 800;
  color: var(--primary);
  letter-spacing: 1px;
}

.stat-unit {
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
  margin-left: 2px;
}

.stat p {
  margin-top: 4px;
  color: var(--text-light);
  font-size: 15px;
}

/* ============ 通用 section ============ */
.section {
  padding: 96px 0;
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 60px;
}

.section-tag {
  display: inline-block;
  padding: 6px 18px;
  border-radius: 999px;
  background: var(--bg-blue);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 2px;
  margin-bottom: 18px;
}

.section-head h2 {
  font-size: 36px;
  font-weight: 800;
  letter-spacing: 1px;
  margin-bottom: 16px;
}

.section-head p {
  color: var(--text-light);
  font-size: 16px;
}

/* ============ 关于我们 ============ */
.about {
  background: var(--bg-soft);
}

.about-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
  align-items: center;
}

.about-text h3 {
  font-size: 26px;
  font-weight: 700;
  margin-bottom: 18px;
}

.about-text p {
  color: var(--text);
  margin-bottom: 16px;
  font-size: 15.5px;
}

.about-list {
  list-style: none;
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.about-list li {
  position: relative;
  padding-left: 28px;
  color: var(--ink);
  font-weight: 500;
}

.about-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 0;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-size: 12px;
  display: grid;
  place-items: center;
}

.about-cards {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.about-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px;
  display: flex;
  gap: 20px;
  align-items: flex-start;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.about-card-icon {
  flex-shrink: 0;
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background: var(--bg-blue);
  color: var(--primary);
  font-weight: 800;
  font-size: 16px;
  display: grid;
  place-items: center;
}

.about-card h4 {
  font-size: 17px;
  margin-bottom: 6px;
}

.about-card p {
  color: var(--text-light);
  font-size: 14.5px;
}

/* ============ 志愿服务 ============ */
.services {
  background: #fff;
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.service-card {
  padding: 34px 30px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.service-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.service-icon {
  width: 60px;
  height: 60px;
  border-radius: 16px;
  background: var(--bg-blue);
  display: grid;
  place-items: center;
  margin-bottom: 22px;
}

.service-icon svg {
  fill: var(--primary);
}

.service-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
}

.service-card p {
  color: var(--text-light);
  font-size: 15px;
}

/* ============ 志愿项目 ============ */
.projects {
  background: var(--bg-soft);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  max-width: 1180px;
  margin: 0 auto;
}

@media (max-width: 900px) {
  .projects-grid {
    grid-template-columns: 1fr;
    max-width: 640px;
  }
}

.project-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.project-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.project-thumb {
  height: 160px;
  display: grid;
  place-items: center;
}

.project-thumb svg {
  fill: #fff;
}

.thumb-iq {
  background: linear-gradient(135deg, #16a34a, #0d9488);
}

.iq-badge {
  font-size: 60px;
  font-weight: 800;
  color: #fff;
  letter-spacing: 4px;
  line-height: 1;
}

.thumb-pscg {
  background: linear-gradient(135deg, #7c3aed, #4f46e5);
}

.pscg-badge {
  font-size: 44px;
  font-weight: 800;
  color: #fff;
  letter-spacing: 5px;
  line-height: 1;
}

.thumb-social {
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
}

.social-badge {
  font-size: 54px;
  font-weight: 800;
  color: #fff;
  letter-spacing: 6px;
  line-height: 1;
}

.project-body {
  padding: 26px;
}

.project-cat {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--primary);
  background: var(--bg-blue);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 14px;
}

.project-body h3 {
  font-size: 19px;
  margin-bottom: 10px;
}

.project-body p {
  color: var(--text-light);
  font-size: 14.5px;
  margin-bottom: 18px;
}

.project-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--text-light);
}

.project-link {
  color: var(--primary);
  font-weight: 600;
}

.project-link:hover {
  color: var(--primary-dark);
}

/* ============ 志愿游戏专区 ============ */
.games {
  background: #fff;
}

.games-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  max-width: 900px;
  margin: 0 auto;
}

@media (max-width: 900px) {
  .games-grid {
    grid-template-columns: 1fr;
    max-width: 640px;
  }
}

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

.game-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.game-thumb {
  height: 160px;
  display: grid;
  place-items: center;
  position: relative;
}

.thumb-ddz {
  background: linear-gradient(135deg, #dc2626, #b91c1c);
}

.ddz-suit {
  position: absolute;
  font-size: 42px;
  color: rgba(255, 255, 255, 0.28);
  line-height: 1;
}

.ddz-suit:nth-child(1) { top: 18px; left: 26px; transform: rotate(-16deg); }
.ddz-suit:nth-child(2) { top: 26px; right: 30px; transform: rotate(14deg); }
.ddz-suit:nth-child(3) { bottom: 18px; left: 46px; transform: rotate(10deg); }

.ddz-badge {
  position: relative;
  z-index: 1;
  font-size: 34px;
  font-weight: 800;
  color: #fff;
  letter-spacing: 6px;
  text-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}

.thumb-soon {
  background: linear-gradient(135deg, #94a3b8, #64748b);
}

.soon-badge {
  font-size: 24px;
  font-weight: 800;
  color: #fff;
  letter-spacing: 6px;
}

.game-body {
  padding: 26px;
}

.game-cat {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: #b91c1c;
  background: #fef2f2;
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 14px;
}

.game-body h3 {
  font-size: 19px;
  margin-bottom: 10px;
}

.game-body p {
  color: var(--text-light);
  font-size: 14.5px;
  margin-bottom: 18px;
}

.game-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--text-light);
}

/* ============ 新闻动态 ============ */
.news {
  background: #fff;
}

.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.news-card {
  display: flex;
  gap: 20px;
  padding: 28px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.news-date {
  flex-shrink: 0;
  text-align: center;
  width: 62px;
}

.news-date strong {
  display: block;
  font-size: 30px;
  font-weight: 800;
  color: var(--primary);
  line-height: 1.1;
}

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

.news-body h3 {
  font-size: 17px;
  margin-bottom: 10px;
  line-height: 1.5;
}

.news-body p {
  color: var(--text-light);
  font-size: 14px;
  margin-bottom: 14px;
}

.news-link {
  color: var(--primary);
  font-size: 14px;
  font-weight: 600;
}

.news-link:hover {
  color: var(--primary-dark);
}

/* ============ 加入我们 ============ */
.join {
  background: #fff;
}

.join-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  padding: 56px 60px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, #052e16 0%, #15803d 55%, #16a34a 100%);
  color: #fff;
}

.join-box .section-tag {
  background: rgba(255, 255, 255, 0.14);
  color: var(--accent);
}

.join-text {
  max-width: 640px;
}

.join-text h2 {
  font-size: 32px;
  margin-bottom: 16px;
}

.join-text p {
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 22px;
}

.join-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.join-list li {
  position: relative;
  padding-left: 26px;
  color: rgba(255, 255, 255, 0.9);
}

.join-list li::before {
  content: "✦";
  position: absolute;
  left: 0;
  color: var(--accent);
}

/* ============ 联系我们 ============ */
.contact {
  background: var(--bg-soft);
}

.contact-card {
  max-width: 560px;
  margin: 0 auto;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: 44px 40px;
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.contact-card-logo {
  width: 84px;
  height: 84px;
  margin: 0 auto 20px;
  border-radius: 24px;
  background: linear-gradient(135deg, var(--primary), var(--primary-deep));
  color: #fff;
  font-size: 40px;
  font-weight: 800;
  display: grid;
  place-items: center;
  box-shadow: 0 10px 26px rgba(22, 163, 74, 0.35);
}

.contact-card-name h3 {
  font-size: 24px;
  line-height: 1.5;
  margin-bottom: 6px;
  color: var(--ink);
  letter-spacing: 1px;
}

.contact-card-desc {
  color: var(--text);
  font-size: 15px;
  line-height: 1.8;
  padding: 0 10px 24px;
  border-bottom: 1px dashed var(--border);
  margin-bottom: 24px;
}

.contact-card-items {
  display: grid;
  gap: 16px;
  text-align: left;
}

.contact-card-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 18px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.contact-card-icon {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--bg-blue);
  display: grid;
  place-items: center;
}

.contact-card-icon svg {
  fill: var(--primary);
}

.contact-card-item h4 {
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 2px;
  font-weight: 600;
}

.contact-card-item p {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.5px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

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

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--ink);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 15px;
  font-family: inherit;
  color: var(--ink);
  background: #fafbfd;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(22, 163, 74, 0.14);
  background: #fff;
}

.form-tip {
  margin-top: 12px;
  font-size: 14px;
  color: #16a34a;
  min-height: 20px;
}

.form-tip.error {
  color: #dc2626;
}

/* ============ 页脚 ============ */
.footer {
  background: #052e16;
  color: #fff;
  padding-top: 64px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 48px;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.7);
  margin-top: 16px;
  letter-spacing: 2px;
}

.footer-col h4 {
  font-size: 16px;
  margin-bottom: 18px;
  color: #fff;
}

.footer-col a {
  display: block;
  color: rgba(255, 255, 255, 0.72);
  font-size: 14.5px;
  margin-bottom: 12px;
  transition: color 0.2s ease;
}

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

.footer-sub {
  color: rgba(255, 255, 255, 0.72);
  font-size: 14px;
  margin-bottom: 10px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding: 20px 0;
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.55);
  font-size: 13.5px;
  text-align: center;
}

/* ============ 返回顶部 ============ */
.back-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  border: none;
  cursor: pointer;
  display: grid;
  place-items: center;
  box-shadow: 0 8px 20px rgba(22, 163, 74, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
  z-index: 90;
}

.back-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-top:hover {
  background: var(--primary-dark);
}

.back-top svg {
  fill: #fff;
}

/* ============ 无障碍朗读 ============ */
.reader {
  position: fixed;
  right: 28px;
  bottom: 88px;
  z-index: 95;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 12px;
}

.reader-bar {
  display: flex;
  align-items: center;
  gap: 14px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 8px 10px 8px 18px;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
}

.reader-bar.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.reader-status {
  font-size: 13px;
  color: var(--text);
  max-width: 210px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.reader-prev,
.reader-next {
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  padding: 7px 12px;
  border-radius: 999px;
  font-size: 13px;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.reader-prev:hover,
.reader-next:hover {
  border-color: var(--primary);
  background: var(--bg-blue);
}

.reader-stop {
  border: none;
  background: #fef2f2;
  color: #dc2626;
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease;
}

.reader-stop:hover {
  background: #fee2e2;
}

.reader-toggle {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  border: 2px solid #fff;
  cursor: pointer;
  display: grid;
  place-items: center;
  box-shadow: 0 8px 20px rgba(22, 163, 74, 0.4);
  transition: background 0.2s ease, transform 0.2s ease;
}

.reader-toggle:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
}

.reader-toggle svg {
  fill: #fff;
  width: 22px;
  height: 22px;
}

.reader-toggle .ic-pause {
  display: none;
}

.reader-toggle.playing .ic-play {
  display: none;
}

.reader-toggle.playing .ic-pause {
  display: block;
}

/* 当前朗读段落高亮 */
.reader-active {
  background: rgba(251, 191, 36, 0.22) !important;
  border-radius: 6px;
  outline: 2px solid rgba(251, 191, 36, 0.6);
  outline-offset: 1px;
}

/* ============ 滚动显现动画 ============ */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .services-grid,
  .news-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-grid {
    grid-template-columns: 1fr;
  }

  .contact-card {
    padding: 34px 22px;
  }

  .contact-card-logo {
    width: 72px;
    height: 72px;
    font-size: 34px;
    border-radius: 20px;
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 78%;
    max-width: 320px;
    height: 100vh;
    flex-direction: column;
    justify-content: center;
    gap: 28px;
    background: #fff;
    box-shadow: -10px 0 40px rgba(15, 23, 42, 0.16);
    transition: right 0.35s ease;
    padding: 40px;
  }

  .nav.open {
    right: 0;
  }

  .nav .nav-link {
    color: var(--ink);
    font-size: 18px;
  }

  .nav .nav-link:hover,
  .nav .nav-link.active {
    color: var(--primary);
  }

  .nav-cta {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

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

  .hero {
    padding: 130px 0 150px;
    background:
      linear-gradient(180deg, transparent 0 86%, #ffffff 86%),
      linear-gradient(135deg, #052e16 0%, #15803d 45%, #16a34a 100%);
  }

  .hero-content h1 {
    font-size: 34px;
  }

  .hero-panel {
    grid-template-columns: 1fr;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .services-grid,
  .news-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 68px 0;
  }

  .section-head h2 {
    font-size: 28px;
  }

  .join-box {
    flex-direction: column;
    align-items: flex-start;
    padding: 40px 30px;
  }

  .form-row {
    grid-template-columns: 1fr;
  }
}