/**
 * MNA 官网全局组件样式
 * 按钮、卡片、导航、页脚、手风琴等全局可复用组件
 */

/* ========================================
   1. 按钮 .btn
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: var(--radius-md);
  font-weight: 500;
  font-size: 16px;
  line-height: 1.5;
  transition: all 0.3s ease;
  text-decoration: none;
  cursor: pointer;
}

/* 主按钮 — 深绿底白字 */
.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-white);
  border: 2px solid var(--color-primary);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: var(--color-white);
}

/* 次要按钮 — 白底深绿边框 */
.btn--secondary {
  background-color: var(--color-white);
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn--secondary:hover {
  background-color: var(--color-primary);
  color: var(--color-white);
  transform: translateY(-2px);
}

/* 文字按钮 — 无背景，hover 下划线从左展开 */
.btn--text {
  background-color: transparent;
  color: var(--color-primary);
  border: none;
  padding: 8px 0;
  position: relative;
}

.btn--text::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.btn--text:hover::after {
  transform: scaleX(1);
}

/* ========================================
   2. 卡片 .card
   ======================================== */

.card {
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.card__image {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.card__body {
  padding: var(--space-4);
}

.card__title {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.card__text {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ========================================
   3. 标签 .badge
   ======================================== */

.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-primary);
  background-color: var(--color-bg-light);
  border-radius: var(--radius-sm);
}

/* ========================================
   4. 导航栏 .site-header
   ======================================== */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  height: 64px;
  background-color: transparent;
  transition: background-color 0.3s ease, box-shadow 0.3s ease, backdrop-filter 0.3s ease;
}

.site-header.scrolled {
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.site-header__logo {
  display: flex;
  align-items: center;
  height: 40px;
}

.site-header__logo img {
  height: 100%;
  width: auto;
  display: block;
}

/* 导航链接 */
.nav-links {
  display: none;
  align-items: center;
  gap: var(--space-4);
}

.nav-links__item {
  position: relative;
}

.nav-links__link {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
  padding: 8px 0;
  position: relative;
  transition: color 0.2s ease;
}

.nav-links__link::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.nav-links__link:hover {
  color: var(--color-primary);
}

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

.nav-links__link.active {
  color: var(--color-primary);
}

.nav-links__link.active::after {
  transform: scaleX(1);
}

/* CTA 按钮在导航栏 */
.site-header__cta {
  display: none;
}

/* 汉堡按钮 */
.hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 6px;
  cursor: pointer;
  z-index: 1001;
}

.hamburger__line {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-primary);
  border-radius: 1px;
  transition: all 0.3s ease;
  transform-origin: center;
}

.hamburger.active .hamburger__line:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.hamburger.active .hamburger__line:nth-child(2) {
  opacity: 0;
}

.hamburger.active .hamburger__line:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* 桌面端导航显示 */
@media (min-width: 1024px) {
  .site-header {
    height: 72px;
  }

  .nav-links {
    display: flex;
  }

  .site-header__cta {
    display: inline-flex;
  }

  .hamburger {
    display: none;
  }
}

/* ========================================
   5. 全屏移动菜单 .mobile-menu
   ======================================== */

.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background-color: var(--color-white);
  z-index: 999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transform: translateY(-100%);
  transition: transform 0.4s ease;
  padding: var(--space-6);
}

.mobile-menu.active {
  transform: translateY(0);
}

.mobile-menu__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-4);
}

.mobile-menu__link {
  font-size: 24px;
  font-weight: 500;
  color: var(--color-text);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.4s ease, transform 0.4s ease, color 0.2s ease;
}

.mobile-menu.active .mobile-menu__link {
  opacity: 1;
  transform: translateY(0);
}

/* stagger 淡入 */
.mobile-menu.active .mobile-menu__link:nth-child(1) {
  transition-delay: 0.1s;
}

.mobile-menu.active .mobile-menu__link:nth-child(2) {
  transition-delay: 0.15s;
}

.mobile-menu.active .mobile-menu__link:nth-child(3) {
  transition-delay: 0.2s;
}

.mobile-menu.active .mobile-menu__link:nth-child(4) {
  transition-delay: 0.25s;
}

.mobile-menu.active .mobile-menu__link:nth-child(5) {
  transition-delay: 0.3s;
}

.mobile-menu.active .mobile-menu__link:nth-child(6) {
  transition-delay: 0.35s;
}

.mobile-menu__link:hover {
  color: var(--color-primary);
}

.mobile-menu__lang {
  margin-top: var(--space-6);
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.4s ease 0.4s, transform 0.4s ease 0.4s;
}

.mobile-menu__lang span {
  color: var(--color-primary);
}

.mobile-menu__lang a {
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.mobile-menu__lang a:hover {
  color: var(--color-primary);
}

.mobile-menu.active .mobile-menu__lang {
  opacity: 1;
  transform: translateY(0);
}

@media (min-width: 1024px) {
  .mobile-menu {
    display: none;
  }
}

/* ========================================
   6. 页脚 .site-footer
   ======================================== */

.site-footer {
  background-color: var(--color-bg-light);
  padding: var(--space-10) 0 var(--space-5);
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
  margin-bottom: var(--space-8);
}

.site-footer__col {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.site-footer__logo {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-text);
}

.site-footer__logo span {
  color: var(--color-primary);
}

.site-footer__desc {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  max-width: 280px;
}

.site-footer__title {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.site-footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.site-footer__link {
  font-size: 15px;
  color: var(--color-text-secondary);
  transition: color 0.2s ease;
}

.site-footer__link:hover {
  color: var(--color-primary);
}

.site-footer__contact {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.site-footer__contact-item {
  font-size: 15px;
  color: var(--color-text-secondary);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.site-footer__social {
  display: flex;
  gap: var(--space-3);
  margin-top: var(--space-2);
}

.site-footer__social-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background-color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.site-footer__social-icon:hover {
  background-color: var(--color-primary);
  transform: translateY(-2px);
}

.site-footer__social-icon svg {
  width: 18px;
  height: 18px;
  fill: var(--color-text-secondary);
  transition: fill 0.2s ease;
}

.site-footer__social-icon:hover svg {
  fill: var(--color-white);
}

/* 版权栏 */
.site-footer__bottom {
  border-top: 1px solid rgba(0, 140, 69, 0.15);
  padding-top: var(--space-3);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.site-footer__copyright {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* 响应式页脚网格 */
@media (min-width: 768px) {
  .site-footer__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .site-footer__grid {
    grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: var(--space-8);
  }

  .site-footer__bottom {
    flex-direction: row;
    justify-content: space-between;
  }
}

/* ========================================
   7. CTA 浮动按钮 .cta-fab（仅移动端）
   ======================================== */

.cta-fab {
  position: fixed;
  bottom: var(--space-4);
  right: var(--space-4);
  z-index: 998;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: var(--space-2);
}

.cta-fab__main {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  background-color: var(--color-primary);
  color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  z-index: 2;
}

.cta-fab__main:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-lg);
}

.cta-fab__main svg {
  width: 24px;
  height: 24px;
  transition: transform 0.3s ease;
}

.cta-fab.active .cta-fab__main svg {
  transform: rotate(45deg);
}

.cta-fab__items {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: var(--space-2);
  position: absolute;
  bottom: 64px;
  right: 0;
  pointer-events: none;
}

.cta-fab__item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
}

.cta-fab.active .cta-fab__item {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

/* stagger 展开 */
.cta-fab.active .cta-fab__item:nth-child(1) {
  transition-delay: 0.05s;
}

.cta-fab.active .cta-fab__item:nth-child(2) {
  transition-delay: 0.1s;
}

.cta-fab.active .cta-fab__item:nth-child(3) {
  transition-delay: 0.15s;
}

.cta-fab__item-label {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
  background-color: var(--color-white);
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  white-space: nowrap;
}

.cta-fab__item-btn {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  background-color: var(--color-white);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.cta-fab__item-btn:hover {
  background-color: var(--color-primary);
  color: var(--color-white);
  transform: scale(1.05);
}

.cta-fab__item-btn svg {
  width: 20px;
  height: 20px;
}

/* 桌面端隐藏 FAB */
@media (min-width: 1024px) {
  .cta-fab {
    display: none;
  }
}

/* ========================================
   8. 返回顶部 .back-to-top
   ======================================== */

.back-to-top {
  position: fixed;
  bottom: var(--space-4);
  right: var(--space-4);
  z-index: 997;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  background-color: var(--color-primary);
  color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.3s ease, transform 0.3s ease, background-color 0.2s ease;
  pointer-events: none;
}

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

.back-to-top:hover {
  background-color: #006b36;
}

/* 箭头图标 — CSS 绘制 */
.back-to-top__arrow {
  width: 0;
  height: 0;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  border-bottom: 12px solid currentColor;
}

/* 移动端 FAB 存在时，返回顶部按钮上移 */
@media (max-width: 1023px) {
  .back-to-top {
    bottom: calc(var(--space-4) + 64px);
  }
}

/* ========================================
   9. 手风琴 .accordion
   ======================================== */

.accordion {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.accordion__item {
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.accordion__question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-2) 0;
  font-size: 18px;
  font-weight: 500;
  color: var(--color-text);
  text-align: left;
  cursor: pointer;
  transition: color 0.2s ease;
}

.accordion__question:hover {
  color: var(--color-primary);
}

.accordion__icon {
  width: 24px;
  height: 24px;
  position: relative;
  flex-shrink: 0;
  margin-left: var(--space-2);
}

.accordion__icon::before,
.accordion__icon::after {
  content: "";
  position: absolute;
  background-color: var(--color-primary);
  transition: transform 0.3s ease;
}

/* 横线 */
.accordion__icon::before {
  width: 14px;
  height: 2px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

/* 竖线 */
.accordion__icon::after {
  width: 2px;
  height: 14px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

/* active 时竖线旋转 90° 变成横线，+ 变 - */
.accordion__item.active .accordion__icon::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.accordion__answer {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height 0.3s ease, opacity 0.3s ease, padding 0.3s ease;
}

.accordion__item.active .accordion__answer {
  max-height: 500px;
  opacity: 1;
  padding-bottom: var(--space-3);
}

.accordion__answer-text {
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

/* ========================================
   10. 医疗免责声明 .medical-disclaimer
   ======================================== */

.medical-disclaimer {
  font-size: 14px;
  line-height: 1.6;
  color: var(--color-text-secondary);
  padding: var(--space-2) 0;
  padding-left: var(--space-2);
  border-left: 3px solid var(--color-primary);
  background-color: rgba(0, 140, 69, 0.05);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

/* ========================================
   11. 页面头图 .page-hero
   ======================================== */

.page-hero {
  position: relative;
  height: 40vh;
  min-height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.page-hero__bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 1;
}

.page-hero__overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.4);
  z-index: 2;
}

.page-hero__content {
  position: relative;
  z-index: 3;
  text-align: center;
  color: var(--color-white);
  padding: 0 var(--container-padding);
}

.page-hero__title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--space-2);
}

.page-hero__subtitle {
  font-size: 18px;
  font-weight: 400;
  opacity: 0.9;
}

@media (min-width: 1024px) {
  .page-hero__title {
    font-size: 48px;
  }

  .page-hero__subtitle {
    font-size: 20px;
  }
}