:root {
  --page-bg: #f3f6f9;
  --white: #ffffff;

  /* 整体缩小到约 1/2 */
  --header-height: 55px;
  --nav-height: 33px;

  --brand-blue: #1b57c9;
  --nav-blue: #597ef3;
  --icon-blue: #597ef3;
  --tab-active-text: #4aa8df;

  --content-bg: #ffffff;

  /* 1920 设计稿缩小 1/2 后的关键定位 */
  --header-padding-left: 10vw;
  --header-padding-right: 10vw;

  --brand-gap: 14px;
  --top-right-gap: 30px;

  --nav-padding-left: 10vw;
  --nav-padding-right: 10vw;
  --nav-title-gap: 19px;
  --nav-tabs-gap: 46px;

  --nav-title-letter-spacing: 7px;
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background: var(--page-bg);
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
}

body {
  min-width: 960px;
}

button,
input,
select,
textarea {
  font: inherit;
}

a {
  text-decoration: none;
}

.page-shell {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  background: var(--page-bg);
}

/* =========================
   顶部
========================= */
.top-header {
  height: var(--header-height);
  background: var(--white);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-left: var(--header-padding-left);
  padding-right: var(--header-padding-right);
}

.top-header__left {
  display: flex;
  align-items: center;
  min-width: 380px;
}

.brand-wrap {
  display: flex;
  align-items: center;
  gap: var(--brand-gap);
  white-space: nowrap;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 7px;
  color: var(--brand-blue);
  line-height: 1;
}

.brand-logo__en {
  font-size: 30px;
  font-weight: 800;
  font-style: italic;
  letter-spacing: -1.8px;
  color: var(--brand-blue);
  display: inline-block;
  transform: scaleY(0.82);
  transform-origin: left center;
}

.brand-logo__cn {
  font-size: 16px;
  font-weight: 700;
  color: var(--brand-blue);
  letter-spacing: 0.5px;
  margin-top: 2px;
}

.brand-title {
  font-size: 24px;
  font-weight: 500;
  color: var(--brand-blue);
  letter-spacing: 2px;
  margin-top: 1px;
  font-family: KaiTi, Arial, "Microsoft YaHei", 宋体, sans-serif;
}

.top-header__right {
  display: flex;
  align-items: flex-start;
  gap: var(--top-right-gap);
  padding-top: 2px;
}

.tool-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  color: var(--icon-blue);
  white-space: nowrap;
  user-select: none;
}

.tool-text {
  margin-top: 4px;
  font-size: 12px;
  line-height: 1;
  color: var(--icon-blue);
  font-weight: 400;
}

.empty-text {
  opacity: 0;
}

.tool-icon {
  width: 25px;
  height: 25px;
  position: relative;
  display: inline-block;
  flex: 0 0 auto;
}

/* 扇形图标 */
.icon-pie {
  border-radius: 50%;
  background:
    conic-gradient(
      var(--icon-blue) 0deg 90deg,
      transparent 90deg 96deg,
      var(--icon-blue) 96deg 208deg,
      transparent 208deg 214deg,
      var(--icon-blue) 214deg 360deg
    );
}

.icon-pie::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 0;
  width: 2px;
  height: 19px;
  background: #fff;
  border-radius: 2px;
}

.icon-pie::after {
  content: "";
  position: absolute;
  left: 9px;
  top: 9px;
  width: 8px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
}

/* 文件图标 */
.icon-file {
  border: 2px solid var(--icon-blue);
  border-radius: 2px;
  background: #fff;
}

.icon-file::before {
  content: "";
  position: absolute;
  right: -1px;
  top: -1px;
  width: 6px;
  height: 6px;
  background: #fff;
  border-left: 2px solid var(--icon-blue);
  border-bottom: 2px solid var(--icon-blue);
  transform: rotate(45deg) translate(1px, -2px);
}

.icon-file::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  width: 8px;
  height: 2px;
  background: var(--icon-blue);
  border-radius: 2px;
  box-shadow: 0 4px 0 var(--icon-blue);
}

/* 菜单图标 */
.icon-menu::before,
.icon-menu::after,
.icon-menu i {
  content: "";
  position: absolute;
  left: 3px;
  width: 22px;
  height: 4px;
  border-radius: 2px;
  background: var(--icon-blue);
}

.icon-menu::before {
  top: 1px;
}

.icon-menu i {
  top: 8px;
  font-style: normal;
}

.icon-menu::after {
  top: 15px;
}

/* 用户图标 */
.icon-user::before {
  content: "";
  position: absolute;
  top: 1px;
  left: 50%;
  width: 12px;
  height: 12px;
  transform: translateX(-50%);
  background: var(--icon-blue);
  border-radius: 50%;
}

.icon-user::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 1px;
  width: 20px;
  height: 10px;
  transform: translateX(-50%);
  background: var(--icon-blue);
  border-radius: 8px 8px 4px 4px;
}

/* =========================
   导航
========================= */
.nav-bar {
  height: var(--nav-height);
  background: var(--nav-blue);
  display: flex;
  align-items: center;
  padding-left: var(--nav-padding-left);
  padding-right: var(--nav-padding-right);
  overflow: hidden;
}

.nav-bar__title {
  flex: 0 0 auto;
  font-size: 18px;
  line-height: 1;
  font-weight: 700;
  color: #fff;
  letter-spacing: var(--nav-title-letter-spacing);
  white-space: nowrap;
  margin-right: var(--nav-title-gap);
  transform: translateY(-1px);
}

.nav-tabs {
  height: 100%;
  display: flex;
  align-items: flex-end;
  gap: var(--nav-tabs-gap);
}

.nav-tab {
  min-width: 73px;
  height: 27px;
  margin-top: 2px;
  padding: 0 12px 5px;
  border: none;
  outline: none;
  border-radius: 7px 7px 0 0;
  background: transparent;
  color: #fff;
  font-size: 14px;
  font-weight: 200;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.nav-tab:hover {
  background: rgba(255, 255, 255, 0.12);
}

.nav-tab.active {
  background: #fff;
  color: var(--tab-active-text);
}

/* =========================
   内容区
========================= */
.page-main {
  flex: 1;
  position: relative;
  background: var(--content-bg);
  overflow: hidden;
}

.page-frame {
  width: 100%;
  height: 100%;
  display: block;
  border: none;
  background: #fff;
}

.frame-fallback {
  position: absolute;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  background: #fff;
  color: #758392;
}

.frame-fallback h2 {
  margin: 0 0 12px;
  color: var(--nav-blue);
  font-size: 20px;
  font-weight: 600;
}

.frame-fallback p {
  margin: 0;
  font-size: 12px;
}