/* 基础变量 - 融合 info-bright 风格 */
:root {
  /* 主色调 - 青春校园纸艺 */
  --clr-primary: #0ea5e9;      /* 天空蓝 */
  --clr-secondary: #10b981;    /* 薄荷绿 */
  --clr-accent: #6366f1;       /* 静谧紫 */
  --clr-bg: #fffcf0;           /* 学院米黄背景 */
  --clr-light: #ffffff;        /* 纯白 */
  
  /* 辅助色 */
  --clr-yellow: #f0f9ff;       /* 晨曦蓝 (替代原黄) */
  --clr-blue-soft: #e0f2fe;    /* 淡蓝 */
  --clr-pink-soft: #f5f3ff;    /* 淡紫 */
  --clr-green-soft: #ecfdf5;   /* 淡绿 */
  
  /* 文字颜色 */
  --clr-text-main: #2C3E50;
  --clr-text-muted: #64748b;

  /* 圆角与阴影 */
  --radius: 12px;
  --radius-lg: 16px;
  --radius-btn: 8px;           /* 统一按钮圆角 */
  --shadow: 0 8px 24px rgba(0,0,0,.08);
  --shadow-sm: 0 4px 12px rgba(0,0,0,0.03);
  --shadow-hover: 0 12px 32px rgba(0,0,0,.12);
  --transition: .3s cubic-bezier(0.4, 0, 0.2, 1);
  --header-height: 64px;

  --font-rounded: 'LXGW WenKai', 'Microsoft YaHei UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;

  /* 全局背景纹理规范 - 精细校园坐标纸 (Fine Grid) */
  --global-bg-texture: 
    linear-gradient(rgba(43, 76, 126, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(43, 76, 126, 0.06) 1px, transparent 1px);
  --global-bg-size: 20px 20px;
  --global-bg-color: #fffcf0;
}

/* 全局背景工具类 */
.campus-paper-bg {
  background-color: var(--global-bg-color) !important;
  background-image: var(--global-bg-texture) !important;
  background-size: var(--global-bg-size) !important;
  background-attachment: fixed !important;
}

.paint-stable {
  contain: paint;
  isolation: isolate;
  -webkit-font-smoothing: antialiased;
  text-rendering: geometricPrecision;
}

/* 首页首屏专用透明纹理层 */
.campus-texture-overlay {
  background-image: var(--global-bg-texture) !important;
  background-size: var(--global-bg-size) !important;
  opacity: 0.7;
}

.washi-tape {
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%) rotate(var(--washi-rot, -1deg));
  width: 80%;
  height: 16px;
  opacity: 0.6;
  pointer-events: none;
  z-index: 5;
}
.washi-blue { background: #bae6fd; }
.washi-pink { background: #ddd6fe; }
.washi-green { background: #a7f3d0; }
.washi-yellow { background: #fed7aa; }
.washi-rose { background: #fecdd3; }

/* 全局重置 */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  scroll-behavior: smooth;
}
body {
  font-family: var(--font-rounded);
  background: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.6;
}
img {
  max-width: 100%;
  display: block;
  border-radius: var(--radius);
}
a {
  text-decoration: none;
  color: inherit;
}

input[type="password"]::-ms-reveal,
input[type="password"]::-ms-clear {
  display: none;
}

/* 布局容器 */
.container {
  width: 95%; /* 增加宽度以容纳更多菜单 */
  max-width: 1400px;
  margin: 0 auto;
}

.dashboard-layout {
  padding-top: var(--header-height);
}

/* 按钮 - 统一使用 info-bright 风格 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: .6rem 1.5rem;
  border-radius: var(--radius-btn);
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-family: inherit;
  line-height: 1.5;
}
.btn--primary {
  background: linear-gradient(135deg, var(--clr-primary) 0%, #4a8bc8 100%);
  color: var(--clr-light);
  box-shadow: 0 4px 6px -1px rgba(90,155,214,.4);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(90,155,214,.35);
}
.btn--secondary {
  background: var(--clr-light);
  color: var(--clr-primary);
  border: 2px solid var(--clr-primary);
}
.btn--secondary:hover {
  background: var(--clr-blue-soft);
  color: var(--clr-primary);
  transform: translateY(-2px);
}

/* 头部 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(255,249,245,0.98); /* 增加不透明度 */
  z-index: 1000;
  padding: 0; /* 减少内边距 */
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
  height: 64px;
  /* 移除 display: flex; align-items: center; 因为容器内部已经处理了 */
}
.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.header__left {
  display: flex;
  align-items: center;
  height: 100%;
}
.header__actions {
  display: flex;
  align-items: center;
  height: 100%;
}
.logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--clr-primary);
  letter-spacing: 1px;
  margin-right: 3rem; /* 增加 Logo 右侧间距 */
  flex-shrink: 0;
}
.nav {
  display: flex;
  gap: 0.5rem;
  height: 100%;
  /* 移除 align-items: center; 让子元素自动拉伸到高度 */
}

/* 导航项样式 */
.nav__item {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center; /* 保持内容垂直居中 */
}

/* 点击状态（主要用于移动端或需要点击触发的场景，但在桌面端也防止点击关闭） */
.nav__item.is-open .dropdown-menu {
  display: block;
}

.nav__link {
  font-weight: 500;
  padding: 0 1rem;
  height: 40px; /* 保持按钮的高度 */
  display: flex;
  align-items: center;
  border-radius: 8px;
  transition: var(--transition);
  color: #555;
  font-size: 0.95rem;
  cursor: pointer;
  white-space: nowrap; /* 防止换行 */
}

.nav__link:hover,
.nav__item:hover .nav__link {
  background: var(--clr-blue-soft);
  color: var(--clr-primary);
}

.nav__link.active {
  color: var(--clr-primary);
  background: rgba(90, 155, 214, 0.1);
  font-weight: 600;
}

.nav__link i {
  margin-right: 4px;
  font-size: 1.1rem;
}

.dropdown-arrow {
  font-size: 0.9em;
  margin-left: 2px;
  transition: transform 0.3s ease;
}

.nav__item:hover .dropdown-arrow {
  transform: rotate(180deg);
}

/* 下拉菜单样式 */
.dropdown-menu {
  position: absolute;
  top: 100%; /* 相对于 nav__item 底部 */
  left: 0;
  min-width: 180px;
  background: var(--clr-light);
  border-radius: 0 0 8px 8px;
  box-shadow: 0 8px 20px rgba(0,0,0,.1);
  border: 1px solid rgba(0,0,0,.06);
  border-top: none; /* 移除透明边框，让菜单紧贴导航栏 */
  padding: 0.5rem 0;
  display: none;
  z-index: 2001;
  margin-top: 0; 
}

/* 增加一个透明桥梁，防止鼠标移出 nav__item 时菜单消失 */
.nav__item::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -20px;
  height: 20px;
  background: transparent;
  z-index: 2002; /* 确保层级足够高 */
}

.nav__item:hover .dropdown-menu {
  display: block;
  animation: slideDown 0.2s ease-out;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

.dropdown-item {
  display: flex;
  align-items: center;
  padding: 0.7rem 1.2rem;
  color: var(--clr-text);
  font-size: 0.9rem;
  transition: var(--transition);
}

.dropdown-item:hover {
  background: var(--clr-blue-soft);
  color: var(--clr-primary);
}

.dropdown-item i {
  margin-right: 8px;
  font-size: 1.1rem;
  width: 20px;
  text-align: center;
}

/* 用户菜单容器 */
.header__user {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
  margin-left: 1rem;
  cursor: pointer;
}

/* 确保右侧用户菜单在悬停或点击时显示 */
.header__user:hover .dropdown-menu,
.header__user.is-open .dropdown-menu {
  display: block;
}

/* 用户下拉菜单特定样式 (覆盖默认左对齐) */
.user-dropdown-menu {
  left: auto !important;
  right: 0;
  min-width: 160px;
}

.nav__user {
  position: relative;
  margin-left: 1rem;
}
.nav__user > a {
  padding: .4rem .8rem;
  border-radius: 20px;
  background: #f0f0f0;
  font-size: 0.9rem;
}
.nav__user > a:hover {
  background: var(--clr-blue-soft);
  color: var(--clr-primary);
}
.user-menu {
  position: absolute;
  top: calc(100% + 12px);
  right: 0;
  min-width: 160px;
  background: var(--clr-light);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,.06);
  padding: .4rem;
  display: none;
  z-index: 2001;
}
.user-menu.is-open {
  display: block;
}
.user-menu__item {
  display: block;
  padding: .6rem .8rem;
  border-radius: 10px;
  color: var(--clr-text);
}
.user-menu__item:hover {
  background: var(--clr-blue-soft);
  color: var(--clr-primary);
}

/* 英雄区 */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero__bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--clr-bg) 0%, #ffece4 100%);
  z-index: -1;
}
.hero__bg::before {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 1;
}
@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(3deg); }
}
.hero__content {
  max-width: 680px;
  animation: fadeInUp 1s ease-out;
}
.hero__title {
  font-size: 3rem;
  font-weight: 800;
  color: var(--clr-primary);
  margin-bottom: .5rem;
}
.hero__subtitle {
  font-size: 1.5rem;
  color: var(--clr-secondary);
  margin-bottom: 1rem;
}
.hero__desc {
  font-size: 1.1rem;
  margin-bottom: 2.5rem;
  color: var(--clr-text);
}
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 功能区 */
.features {
  padding: 5rem 0;
  background: var(--clr-light);
}
.section-title {
  text-align: center;
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 3rem;
  color: var(--clr-primary);
}
.features__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2.5rem;
}
.feature {
  background: var(--clr-light);
  border-radius: var(--radius);
  padding: 2rem 1.5rem;
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.feature:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 40px rgba(0,0,0,.1);
}
.feature__icon-img {
  width: 120px;
  height: 120px;
  margin: 0 auto 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
}
.feature__icon-img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform 0.3s ease;
}
.feature:hover .feature__icon-img img {
  transform: scale(1.1) rotate(5deg);
}
.feature__title {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: .6rem;
  color: var(--clr-primary);
}
.feature__desc {
  color: #555;
}

/* 作品展示 */
.showcase {
  padding: 5rem 0;
  background: var(--clr-bg);
}
.showcase__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2rem;
}
.showcase__item {
  background: var(--clr-light);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  text-align: center;
  padding-bottom: 1rem;
}
.showcase__item:hover {
  transform: scale(1.03);
  box-shadow: 0 16px 40px rgba(0,0,0,.12);
}
.showcase__item img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  object-position: center top;
  display: block;
  border-radius: var(--radius) var(--radius) 0 0;
}
.showcase__item p {
  margin: 1rem 0 .5rem;
  font-weight: 600;
  color: var(--clr-primary);
}

/* 行动号召 */
.cta {
  padding: 5rem 0;
  background: var(--clr-green-soft);
  color: var(--clr-text);
  text-align: center;
}
.cta__title {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 1rem;
}
.cta__desc {
  font-size: 1.2rem;
  margin-bottom: 2rem;
  opacity: .92;
}

/* 页脚 */
.footer {
  padding: 2rem 0;
  text-align: center;
  font-size: .9rem;
  color: #777;
  background: var(--clr-light);
}

.no-scroll {
  overflow: hidden;
}

/* 响应式 */
@media (max-width: 768px) {
  .nav {
    display: none; /* 暂时隐藏移动端菜单，后续可加汉堡菜单 */
  }
  .hero__title {
    font-size: 2.2rem;
  }
  .hero__subtitle {
    font-size: 1.2rem;
  }
  .section-title {
    font-size: 1.7rem;
  }
  .features__grid,
  .showcase__grid {
    grid-template-columns: 1fr;
  }
}

/* 滚动动画 */
.scroll-animate {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity .6s ease, transform .6s ease;
}
.scroll-animate.visible {
  opacity: 1;
  transform: translateY(0);
}

.modal {
  position: fixed;
  inset: 0;
  display: none;
  z-index: 2000;
}
.modal--open {
  display: block;
}
.modal__overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.5);
}
.modal__dialog {
  position: relative;
  width: 92%;
  max-width: 560px;
  margin: 8vh auto;
  background: var(--clr-light);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.modal__title {
  font-size: 1.4rem;
  font-weight: 700;
  padding: 1.2rem 1.5rem 0.6rem;
  color: var(--clr-primary);
}
.modal__close {
  position: absolute;
  right: 12px;
  top: 10px;
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: #999;
  font-size: 1.5rem;
  cursor: pointer;
}
.modal__close:hover {
  color: var(--clr-primary);
}
.modal__tabs {
  display: flex;
  gap: 1.5rem;
  padding: 0 1.5rem;
  border-bottom: 1px solid rgba(0,0,0,.06);
}
.modal__tab {
  flex: 1;
  padding: .85rem 0;
  border: none;
  background: transparent;
  cursor: pointer;
  font-weight: 700;
  color: #777;
  transition: var(--transition);
  position: relative;
}
.modal__tab::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  background: transparent;
  border-radius: 999px;
  transition: var(--transition);
}
.modal__tab:hover {
  color: var(--clr-primary);
}
.modal__tab:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px rgba(90,155,214,.18);
  border-radius: 10px;
}
.modal__tab.is-active {
  color: var(--clr-primary);
}
.modal__tab.is-active::after {
  background: var(--clr-accent);
}
.modal__body {
  padding: 1.2rem 1.5rem 1.5rem;
}
.form {
  display: none;
}
.form.is-active {
  display: block;
}
.form__group {
  margin-bottom: 1rem;
}
.form__group label {
  display: block;
  font-size: .95rem;
  margin-bottom: .4rem;
  color: #555;
}
.input {
  width: 100%;
  padding: .8rem .9rem;
  border-radius: 10px;
  border: 2px solid #eee;
  outline: none;
  transition: var(--transition);
  font-size: 1rem;
}
.input:focus {
  border-color: var(--clr-primary);
  box-shadow: 0 0 0 3px rgba(90,155,214,.15);
}
.form__actions {
  margin-top: .6rem;
}
.flashes {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
}
.flashes li {
  padding: .75rem .9rem;
  border-radius: 12px;
  background: var(--clr-blue-soft);
  border: 1px solid rgba(90,155,214,.25);
  color: var(--clr-primary);
  font-weight: 600;
}
.flashes li + li {
  margin-top: .6rem;
}
.form__msg {
  margin-top: .8rem;
  font-size: .95rem;
  color: var(--clr-secondary);
}