/* ===== 知知猫家庭版 tutorinfo.html ===== */
body,
html {
  font-family:
    "SF Pro Text", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f6f5fa;
  color: #333333;
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- 头部导航（与 application.html 保持一致） ---------- */
header {
  background-color: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(10px);
  position: fixed;
  width: 100%;
  z-index: 1000;
  transition: all 0.3s ease;
}
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 0;
}
.logo {
  font-size: 24px;
  font-weight: bold;
  color: var(--primary-color);
  text-decoration: none;
}
.logo img {
  display: block;
}
nav ul {
  list-style-type: none;
  display: flex;
  gap: 30px;
}
nav ul li a {
  color: var(--text-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
}
nav ul li a:hover {
  color: var(--primary-color);
}
.productnav {
  position: relative;
}
.productItem {
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.5s ease 0.15s, visibility 0s linear 0.65s;
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  box-shadow: 5px 5px 5px rgba(0, 0, 0, 0.3);
  position: absolute;
  top: 40px;
  left: -78px;
  width: 300px;
  min-height: 146px;
  border-radius: 12px;
  background: #ffffff;
  box-sizing: border-box;
  padding: 24px 16px;
  cursor: pointer;
  font-family: Alibaba PuHuiTi 3;
  font-size: 16px;
  color: #08042c;
}
.productItem::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -16px; /* 覆盖 li 与面板之间的空隙，鼠标可从<a>平滑移到面板 */
  height: 16px;
}

.productItem a {
  color: #08042c;
  display: block;
}
.productItem a:hover {
  color: #8e80ff !important;
}
.more {
  display: inline-block;
  top: 2px;
  left: 4px;
  position: relative;
}
.productnav:hover .productItem {
  opacity: 1;
  visibility: visible;
  transition: opacity 0.5s ease, visibility 0s;
}
nav ul li.active > a,
nav ul li.active > a span {
  color: #8e80ff;
}
.headerbg {
  width: 100%;
  height: 100px;
  background: #fff;
}

/* ---------- banner（位置与 application.html 一致，文案覆盖在图上） ---------- */
.tbhero {
  position: relative;
  height: 600px;
}
.tbhero img {
  display: block;
  width: 100%;
  height: auto;
}
/* 渐变底铺满固定高度的首屏 */
.tbhero .pcft {
  height: 100%;
  object-fit: cover;
}
.tbhero .mbft {
  display: none;
}
/* 文字区 + 右侧插图：同一容器内 space-around 分布（宽度与 .tb-container 一致 1200） */
.tbhero-wrap {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  width: 1200px;
  max-width: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.tbhero-inner {
  display: flex;
  justify-content: center;
}
.tbhero-box {
  width: auto;
  max-width: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.tbhero-pic {
  flex: 0 1 auto;
  width: 50%;
  max-width: 600px;
  height: auto;
}
/* 本页（tutorinfo）首屏内容图：去掉 width:50%，限宽 730 */
.thero .tbhero-pic {
  width: auto;
  max-width: 730px;
  height: auto;
}
.tbhero-pic img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: contain;
}
.tbhero-title {
  margin: 0;
  font-size: 50px;
  font-weight: bold;
  line-height: 1.2;
  color: #08042c;
}
.tbhero-title em {
  font-style: normal;
  color: #7548fd;
}
.tbhero-sub {
  margin: 8px 0 0;
  font-size: 24px;
  line-height: 34px;
  color: #474560;
}
/* 注意：common.css 的 `a:link{background-color:transparent}` 优先级为 0,1,1，
   因此按钮用父级类提升权重，避免纯色背景被重置为透明 */
.tbhero .tbhero-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 32px;
  width: 150px;
  height: 49px;
  border-radius: 100px;
  background: #7548fd;
  color: #ffffff;
  font-size: 16px;
  text-decoration: none;
  transition: all 0.3s ease;
}
.tbhero .tbhero-btn:hover {
  transform: translateY(-2px);
  background: #6a3ff2;
}
.tbhero .tbhero-btn svg {
  width: 20px;
  height: 15px;
  margin-right: 15px;
}

/* ---------- 内容区 ---------- */
.tbmain {
  background: #f6f5fa;
  margin-top: 40px;
  padding: 0 0 62px;
}
/* 首屏需要紧贴内容区的页面（tutorinfo / zhongkao / gaokao）单独加这个类 */
.tbmain.tbmain-tight {
  margin-top: 2px;
}
.tb-container {
  width: 1200px;
  max-width: 100%;
  margin: 0 auto;
  box-sizing: border-box;
}
.tb-card {
  background: #ffffff;
  border-radius: 20px;
}
.tb-card + .tb-card {
  margin-top: 65px;
}

/* 分区标题：前两个字 #08042C 实色，其余渐变 */
.tb-title {
  margin: 0;
  text-align: center;
  font-size: 44px;
  font-weight: bold;
  line-height: 1.2;
  color: #08042c;
}
.tb-grad {
  background: linear-gradient(90deg, #845bfe 0%, #4334ff 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.tb-title.small {
  font-size: 40px;
}

/* 卡片1：5大核心优势 */
.tb-adv {
  padding: 52px 32px 59px;
}
.tb-adv-row {
  display: flex;
  justify-content: space-between;
  margin-top: 70px;
}
.tb-adv-item {
  width: 207px;
  height: 230px;
  box-sizing: border-box;
  padding: 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 1px solid #e3e8f4;
  border-radius: 8px;
  text-align: center;
}
.tb-adv-item:nth-child(1) {
  background: linear-gradient(317.88deg, #f4f6ff 4%, #eff3ff 92.5%);
}
.tb-adv-item:nth-child(2) {
  background: linear-gradient(317.88deg, #f1f5ff 4%, #f9f9ff 92.5%);
}
.tb-adv-item:nth-child(3) {
  background: linear-gradient(317.88deg, #f3fdff 4%, #f3f8fe 92.5%);
}
.tb-adv-item:nth-child(4) {
  background: linear-gradient(317.88deg, #f3f3fb 4%, #f7edf5 92.5%);
}
.tb-adv-item:nth-child(5) {
  background: linear-gradient(317.88deg, #f4f6ff 4%, #eff3ff 92.5%);
}
.tb-adv-item img {
  display: block;
  width: 48px;
  height: 48px;
  margin: 0 auto;
}
.tb-adv-item h3 {
  margin: 28px 0 0;
  font-size: 20px;
  font-weight: normal;
  color: #08042c;
}
.tb-adv-item p {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 20px;
  color: #474560;
}

/* 卡片2：智能双通道学习闭环 */
.tb-loop {
  padding: 50px 32px 49px;
  text-align: center;
}
.tb-loop-img {
  display: block;
  width: 750px;
  max-width: 100%;
  height: auto;
  margin: 43px auto 0;
}

/* 卡片3：3大核心功能 */
.tb-fn {
  padding: 52px 87px 48px;
}
.tb-fn-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.tb-fn-row:first-of-type {
  margin-top: 44px;
}
.tb-fn-row + .tb-fn-row {
  margin-top: 41px;
}
.tb-fn-text {
  width: 330px;
}
.tb-fn-text h3 {
  margin: 0;
  display: flex;
  align-items: center;
  font-size: 30px;
  font-weight: 600;
  line-height: 1.2;
  color: #08042c;
}
/* 序号徽标：32×32、圆角 6.4px、紫蓝渐变底 + 白色数字 */
.tb-fn-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 32px;
  height: 32px;
  margin-right: 12px;
  border-radius: 6.4px;
  background: linear-gradient(90deg, #a771ff 0%, #3e31ff 100%);
  color: #ffffff;
  font-size: 16px;
  font-weight: bold;
  line-height: 1;
}
.tb-fn-text p {
  margin: 11px 0 0;
  font-size: 16px;
  line-height: 24px;
  color: #474560;
}
/* 同样需要提升权重，避免 a:link 的透明背景覆盖白色底 */
.tb-fn-row .tb-fn-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 22px;
  width: 107px;
  height: 41px;
  box-sizing: border-box;
  border-radius: 100px;
  border: 1px solid #7548fd;
  background: #ffffff;
  color: #7548fd;
  font-size: 13px;
  line-height: 1;
  text-decoration: none;
  transition: all 0.3s ease;
}
.tb-fn-row .tb-fn-btn:hover {
  transform: translateY(-2px);
  background: #f6f5fa;
}
.tb-fn-row .tb-fn-btn img {
  display: block;
  width: 8.5px;
  height: 9px;
  margin-left: 5px;
}
.tb-fn-img {
  display: block;
  width: 454px;
  max-width: 100%;
  height: 270px;
  object-fit: cover;
}

/* 窄屏时首屏容器与内容区一起收边，插图按容器宽 50% 等比缩小 */
@media (max-width: 1240px) {
  .tb-container {
    width: 100%;
    padding: 0 24px;
  }
  .tbhero-wrap {
    padding: 0 24px;
    box-sizing: border-box;
  }
  .tbhero-box {
    width: auto;
    padding: 0 24px;
    box-sizing: border-box;
  }
}

/* ---------- 移动端 ---------- */
@media (max-width: 768px) {
  /* 移动端 headerbg 高度 */
  .headerbg {
    height: 70px;
  }
  .tbhero {
    height: auto;
  }
  .tbhero .pcft {
    display: none;
  }
  .tbhero .mbft {
    display: block;
  }
  .tbhero-wrap {
    position: relative;
    z-index: 2;
    padding: 0;
    justify-content: center; /* 移动端只有文案块，需居中 */
    margin-top: -120px; /* 上移 120px，压在移动端 banner 下方留白上 */
  }
  .tbhero-pic {
    display: none;
  }
  .tbhero-box {
    padding: 0 16px 32px;
    align-items: center;
    text-align: center;
  }
  .tbhero-title {
    font-size: 28px;
  }
  .tbhero-sub {
    margin-top: 6px;
    max-width: 100%;
    font-size: 14px;
    line-height: 22px;
  }
  .tbhero .tbhero-btn {
    margin-top: 16px;
    width: 130px;
    height: 40px;
    font-size: 14px;
  }
  .tbhero .tbhero-btn svg {
    width: 17px;
    height: 13px;
    margin-right: 10px;
  }
  .tbmain {
    padding: 8px 0 40px;
  }
  .tb-container {
    padding: 0 16px;
  }
  .tb-card {
    border-radius: 12px;
  }
  .tb-card + .tb-card {
    margin-top: 20px;
  }
  .tb-title,
  .tb-title.small {
    font-size: 24px;
  }
  .tb-adv {
    padding: 24px 16px 28px;
  }
  .tb-adv-row {
    flex-wrap: wrap;
    justify-content: space-between;
    margin-top: 16px;
  }
  .tb-adv-item {
    width: 48%;
    height: auto;
    margin-top: 16px;
    padding: 20px 12px;
  }
  .tb-adv-item img {
    width: 38px;
    height: 38px;
  }
  .tb-adv-item h3 {
    margin-top: 20px;
    font-size: 15px;
  }
  .tb-adv-item p {
    margin-top: 6px;
    font-size: 12px;
    line-height: 17px;
  }
  /* 第 5 个模块独占一行：图标在左，标题/描述左对齐在右，整体水平居中 */
  .tb-adv-item:last-child {
    width: 100%;
    display: grid;
    grid-template-columns: auto auto;
    justify-content: center;
    align-items: center;
    column-gap: 20px;
    text-align: left;
  }
  .tb-adv-item:last-child img {
    grid-column: 1;
    grid-row: 1 / span 2;
  }
  .tb-adv-item:last-child h3 {
    grid-column: 2;
    grid-row: 1;
    margin-top: 0;
  }
  .tb-adv-item:last-child p {
    grid-column: 2;
    grid-row: 2;
    margin-top: 6px;
  }
  .tb-loop {
    padding: 24px 16px 24px;
  }
  .tb-loop-img {
    margin-top: 18px;
  }
  .tb-fn {
    padding: 24px 16px 28px;
  }
  .tb-fn-row,
  .tb-fn-row:first-of-type {
    flex-direction: column;
    align-items: flex-start;
    margin-top: 22px;
  }
  .tb-fn-row .tb-fn-img {
    order: -1;
    margin-bottom: 14px;
  }
  .tb-fn-text {
    width: 100%;
    text-align: center;
  }
  .tb-fn-text h3 {
    justify-content: center;
    font-size: 22px;
  }
  .tb-fn-text p {
    margin-top: 6px;
    font-size: 13px;
    line-height: 20px;
  }
  .tb-fn-row .tb-fn-btn {
    margin-top: 14px;
    width: 100px;
    height: 38px;
  }
  .tb-fn-img {
    width: 100%;
    height: auto;
  }
}