/* =======================================================================
   M77 关于我们专属样式（about.html）
   公共样式（变量、重置、头部、页脚、面包屑、页面标题）见 css/style.css
   ======================================================================= */

/* ---- 英雄大图 ---- */
.about-hero { width: 100%; }
.about-hero img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 2px;
  background: var(--color-dark);
}

/* ---- 品牌介绍文字 ---- */
.about-intro {
  padding-block: clamp(48px, 6vw, 80px);
}
.about-intro__text p {
  font-size: clamp(13px, 1.1vw, 15px);
  color: #444;
  line-height: 2.1;
  margin-bottom: 1.1em;
}
.about-intro__text p:last-child { margin-bottom: 0; }

/* ---- 我们的故事 / 时间线 ---- */
/* ---- 时间线容器 ---- */

.about-timeline {
  padding-block: clamp(56px, 7vw, 96px);
}
.about-timeline .section-head {
  text-align: center;
  margin-bottom: clamp(40px, 5vw, 64px);
}


.timeline-viewport {
  overflow: hidden;                /* 隐藏溢出 */
  margin: 0 auto;
}
.timeline-grid {
  display: flex;
  flex-wrap: nowrap;               /* 不换行 */
  transition: transform 0.5s cubic-bezier(.22, .61, .36, 1);
  will-change: transform;
}
.timeline-item {
  flex: 0 0 calc(100% / 3);        /* 每次显示3个，每个占1/3宽度 */
  box-sizing: border-box;
  padding: 0; /* 与之前保持相似的间距 */
}
.timeline-item__year {
  font-size: clamp(44px, 4.5vw, 68px);
  font-weight: 700;
  color: var(--color-black);
  letter-spacing: -1px;
  line-height: 1;
  margin-bottom: 18px;width: 80%;padding-left: 10%;
}
.timeline-item__sep {
  width: 100%;
  height: 1px;
  background: #000;
  margin-bottom: 20px;
}
.timeline-item__desc {
  font-size: clamp(12px, 1vw, 14px);
  color: #555;
  line-height: 2;width: 70%;padding-left: 10%;
}

/* 箭头导航 */
.timeline-nav {
  display: flex;
  justify-content: center;
  gap: 52px;
  margin-top: clamp(36px, 4vw, 56px);
}
.timeline-nav__btn {
  width: 54px;
  height: 54px;
  border-radius: 50%;
  border: 1px solid #000000;
  background: transparent;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color .25s, color .25s;
  color: #000000;
}
.timeline-nav__btn:hover {
  border-color: #CCCCCC;
  color: #CCCCCC;
}

/* ---- 响应式 ---- */
@media (max-width: 768px) {
  .timeline-grid { grid-template-columns: 1fr; }
  .timeline-item {
    border-left: none;
    border-top: 1px solid #eee;
    padding: clamp(24px, 4vw, 40px) 0;
  }
  .timeline-item:first-child { border-top: none; padding-top: 0;flex: 0 0 calc(100% / 1); }
  .timeline-nav{display: none;}
  
}