/* ============================================
   英语默写卡系统 — 全局样式 v2
   莫兰迪配色 · Doppelrand 双边框卡片 · 药丸按钮
   移动端优先 · 与后端完全解耦
   ============================================ */

/* ---- 基础重置 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ---- CSS 变量（莫兰迪配色） ---- */
:root {
  /* 背景层级 */
  --bg:            #F5F0EB;
  --bg-card:       #FEFCFB;
  --bg-elevated:   #FFFFFF;
  --bg-surface:    #FAF7F4;

  /* 主色（灰棕） */
  --primary:       #8B7E74;
  --primary-light: #A89888;
  --primary-rich:  #6B5E54;
  --primary-dim:   #B0A59A;
  --primary-dark:  #5C5048;

  /* 点缀 */
  --accent:        #A3B5A6;
  --accent-dim:    #8BA68E;

  /* 语义色 */
  --success:       #7BA88A;
  --danger:        #C4A0A0;
  --danger-hover:  #B08888;
  --warning:       #C4B88A;

  /* 文字 */
  --text:          #4A423B;
  --text-dim:      #8A8076;
  --text-muted:    #B5ACA4;

  /* 边框 + 阴影 */
  --border:        rgba(139,126,116,0.12);
  --border-strong: rgba(139,126,116,0.22);
  --shadow-sm:     0 2px 8px rgba(139,126,116,0.06);
  --shadow-md:     0 4px 16px rgba(139,126,116,0.08);

  /* 圆角 + 动效 */
  --radius-sm:     8px;
  --radius:        12px;
  --radius-md:     20px;
  --radius-lg:     28px;
  --radius-full:   100px;
  --ease:          cubic-bezier(0.32, 0.72, 0, 1);

  /* 字体 */
  --font-serif:    "Noto Serif SC", "Source Han Serif SC", Georgia, serif;
  --font-sans:     -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --font-mono:     "SF Mono", "Menlo", Consolas, monospace;
}

/* ---- 基础排版 ---- */
body {
  font-family: var(--font-sans);
  font-size: 14px;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ---- 布局容器 ---- */
.app { display: flex; flex-direction: column; min-height: 100vh; }
.container {
  flex: 1;
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
  padding: 24px 20px;
}

/* ---- 浮动导航栏（毛玻璃胶囊） ---- */
.navbar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  background: rgba(254,252,251,0.88);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  padding: 8px 10px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow-sm);
  margin: 0 auto 24px;
  max-width: 900px;
  flex-shrink: 0;
  position: relative;
  z-index: 100;
}
.navbar-brand {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 600;
  color: var(--primary-dark);
  text-decoration: none;
  padding: 6px 16px;
  letter-spacing: 0.02em;
}
.navbar-menu {
  display: flex;
  gap: 2px;
  align-items: center;
}
.navbar-menu::before {
  content: none;
}
.navbar-menu a {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 13px;
  color: var(--text-dim);
  text-decoration: none;
  transition: all 0.25s var(--ease);
  letter-spacing: 0.02em;
  /* Safari < 14.1 不支持 flex gap，用 margin 兜底保证导航项不挤在一起 */
  margin: 0 1px;
}
.navbar-menu a:hover,
.navbar-menu a.active {
  background: rgba(139,126,116,0.08);
  color: var(--primary-dark);
}
.navbar-right {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-left: 6px;
}
.nav-logout { display: none; }
.navbar-user {
  font-size: 12px;
  color: var(--text-dim);
}
.navbar-campus {
  font-size: 11px;
  padding: 3px 12px;
  border-radius: var(--radius-full);
  background: rgba(139,126,116,0.06);
  border: 0.5px solid var(--border);
  color: var(--primary-dim);
}

/* ---- Doppelrand 双边框卡片 ---- */
.card {
  background: rgba(139,126,116,0.04);
  border-radius: var(--radius-lg);
  padding: 1.5px;
  box-shadow: 0 0 0 1px var(--border);
  margin-bottom: 16px;
}
.card > *:first-child {
  background: var(--bg-elevated);
  border-radius: calc(var(--radius-lg) - 2px);
  padding: 20px;
  box-shadow: inset 0 1px 0 rgba(139,126,116,0.06);
}
/* 对单层卡片内容的兼容（.card 直接包裹内容时） */
.card.card-flat {
  background: var(--bg-elevated);
  padding: 20px;
  border-radius: var(--radius);
}
.card-header {
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 12px;
  letter-spacing: 0.02em;
}

/* ---- 按钮 ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 20px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), background 0.35s var(--ease), border-color 0.35s var(--ease), color 0.35s var(--ease);
  text-decoration: none;
  letter-spacing: 0.02em;
  line-height: 1.4;
}
.btn:hover {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--primary-dim);
  color: #FFFFFF;
  border: 1px solid var(--primary-dim);
}
.btn-primary:hover {
  background: var(--primary);
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(139,126,116,0.2);
}

.btn-danger {
  background: var(--danger);
  color: #FFFFFF;
  border: 1px solid var(--danger);
}
.btn-danger:hover {
  background: var(--danger-hover);
  box-shadow: 0 4px 12px rgba(196,160,160,0.2);
}

.btn-outline {
  background: transparent;
  color: var(--text-dim);
  border: 1px solid var(--border);
}
.btn-outline:hover {
  border-color: var(--primary-dim);
  background: rgba(139,126,116,0.04);
  color: var(--primary-dark);
}

.btn-sm {
  padding: 5px 14px;
  font-size: 12px;
  border-radius: var(--radius-full);
}
.btn-lg {
  padding: 12px 28px;
  font-size: 15px;
  letter-spacing: 0.04em;
}

/* ---- 提示 ---- */
.alert {
  padding: 12px 18px;
  border-radius: var(--radius);
  margin-bottom: 16px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.01em;
}
.alert-error {
  background: rgba(196,160,160,0.1);
  color: #8B5050;
  border: 0.5px solid rgba(196,160,160,0.25);
}
.alert-success {
  background: rgba(163,181,166,0.12);
  color: #4A6B52;
  border: 0.5px solid rgba(163,181,166,0.25);
}
.alert-info {
  background: rgba(139,126,116,0.06);
  color: var(--primary-dark);
  border: 0.5px solid var(--border);
}

/* ---- 表格 ---- */
table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-elevated);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 0 0 1px var(--border);
}
th, td {
  padding: 14px 18px;
  text-align: left;
  font-size: 14px;
}
th {
  background: rgba(139,126,116,0.04);
  font-weight: 700;
  font-size: 11px;
  color: var(--primary-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 1px solid var(--border-strong);
}
td {
  color: var(--text);
  border-bottom: 1px solid rgba(139,126,116,0.04);
  font-weight: 400;
  letter-spacing: 0.01em;
}
tbody tr {
  transition: transform 0.25s var(--ease), background 0.25s var(--ease);
}
tbody tr:hover td {
  background: rgba(139,126,116,0.04);
}
tbody tr:hover {
  transform: translateX(2px);
}

/* ---- 表单 ---- */
.form-group { margin-bottom: 16px; }
.form-group label {
  font-family: var(--font-serif);
  font-size: 12px;
  font-weight: 600;
  color: var(--primary-dim);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 8px;
  display: block;
  padding-left: 8px;
  position: relative;
}
.form-group label::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 10px;
  background: linear-gradient(180deg, var(--primary-dim), var(--primary-dark));
  border-radius: 0 2px 2px 0;
}
.form-control {
  width: 100%;
  padding: 10px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  background: var(--bg-surface);
  outline: none;
  transition: border-color 0.35s var(--ease), box-shadow 0.35s var(--ease), background 0.35s var(--ease);
  letter-spacing: 0.01em;
}
.form-control:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(139,126,116,0.08);
  background: var(--bg-elevated);
}
select.form-control {
  appearance: none;
  background: var(--bg-surface) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%238A8076' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E") no-repeat right 14px center;
  padding-right: 36px;
}
select.form-control option {
  background: var(--bg-elevated);
  color: var(--text);
}
textarea.form-control {
  border-radius: var(--radius);
  resize: vertical;
}

/* ---- 徽章 ---- */
.badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 10px;
  font-weight: 500;
  background: rgba(139,126,116,0.08);
  border: 0.5px solid var(--border);
  color: var(--primary-dim);
  letter-spacing: 0.03em;
}

/* ---- 辅助文字 ---- */
.text-muted { color: var(--text-muted); }
.text-dim   { color: var(--text-dim); }

/* ---- 页脚 ---- */
.footer {
  text-align: center;
  padding: 20px;
  font-size: 12px;
  color: var(--text-muted);
  border-top: 1px solid rgba(139,126,116,0.06);
  flex-shrink: 0;
  letter-spacing: 0.02em;
}

/* ---- 链接 ---- */
a {
  color: var(--primary-dark);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}
a:hover {
  color: var(--primary);
}

/* ---- 分隔线 ---- */
hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 16px 0;
}

/* ---- 滚动条 ---- */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--primary-dim); border-radius: 3px; opacity: 0.5; }
::-webkit-scrollbar-thumb:hover { background: var(--primary); }

/* ---- 动效工具类 ---- */
.animate-hidden {
  opacity: 0;
  transform: translateY(24px);
  filter: blur(4px);
}
.animate-visible {
  opacity: 1;
  transform: translateY(0);
  filter: blur(0);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease), filter 0.6s var(--ease);
}

/* ---- 响应式 ---- */
@media (max-width: 768px) {
  .navbar {
    margin: 0;
    padding: 6px 4px;
    border-radius: 0;
    position: fixed; bottom: 0; top: auto;
    left: 0; right: 0; z-index: 200;
    background: rgba(254,252,251,0.95);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border-top: 1px solid rgba(139,126,116,0.10);
    border-bottom: none;
    max-width: 100%;
    overflow-x: auto;
    justify-content: space-around;
  }
  .navbar-menu {
    display: flex;
    gap: 0;
    flex-wrap: nowrap;
    align-items: center;
    min-width: 0;
  }
  .navbar-menu a {
    font-size: 11px;
    padding: 6px 8px;
    flex-direction: column;
    text-align: center;
    white-space: nowrap;
    flex-shrink: 0;
  }
  .navbar-right { display: none; }
  .nav-logout { color: #C0806B !important; }
  .navbar-menu a.nav-logout { display: inline-flex; }
  .container { padding: 16px 10px 80px; }
  .footer { padding-bottom: 80px; }
  table { display: block; overflow-x: auto; -webkit-overflow-scrolling: touch; }
  .two-col { flex-direction: column !important; }
  .sidebar { width: 100% !important; }
  .page-card, .page-shell { margin-left: -2px; margin-right: -2px; }
  .home-hero { flex-direction: column; gap: 12px; }
  .home-hero .hero-logo img { max-width: 140px; }
  .home-hero .hero-cn { font-size: 24px; }
  .home-grid { grid-template-columns: 1fr !important; }
  .home-stats { grid-template-columns: repeat(2, 1fr) !important; }
  .create-grid { grid-template-columns: 1fr !important; }
  .page-header, .card-header { padding: 16px 16px; }
  .page-card { padding: 20px 16px; }
}

@media (max-width: 480px) {
  .navbar-menu a { font-size: 10px; padding: 5px 6px; }
  .home-hero .hero-cn { font-size: 20px; }
  .home-stats { grid-template-columns: repeat(2, 1fr) !important; }
  .login-card { padding: 36px 24px 32px; }
  .page-title, .create-header { font-size: 18px; }
  .btn-lg { padding: 10px 20px; font-size: 13px; }
}

/* 最小触摸区域 */
@media (pointer: coarse) {
  .btn, .btn-sm, .btn-lg,
  .navbar-menu a,
  input[type="checkbox"], input[type="radio"] {
    min-height: 44px;
    min-width: 44px;
  }
}