/* ============================================================
   校园助手系统 - 公共样式表 v2.0
   现代化设计系统，统一所有页面视觉风格
   ============================================================ */

/* ==================== CSS 变量 (Design Tokens) ==================== */
:root {
  --primary: #6C63FF;
  --primary-light: #8B85FF;
  --primary-dark: #5A52E0;
  --accent: #FF6B9D;
  --success: #10B981;
  --danger: #EF4444;
  --info: #3B82F6;

  --bg-white: #FFFFFF;
  --text-primary: #1E293B;
  --text-secondary: #64748B;
  --text-muted: #94A3B8;
  --border-color: #E2E8F0;
  --border-light: #F1F5F9;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04), 0 1px 4px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06), 0 1px 4px rgba(0,0,0,0.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08), 0 4px 16px rgba(0,0,0,0.04);
  --shadow-xl: 0 24px 64px rgba(0,0,0,0.12), 0 8px 24px rgba(0,0,0,0.06);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;

  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==================== Reset & Base ==================== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html { overflow-x: hidden; width: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Microsoft YaHei", "Helvetica Neue", sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: var(--text-primary);
}

a { text-decoration: none; color: var(--primary); transition: color var(--transition-fast); }
a:hover { color: var(--primary-dark); }

/* 滚动条美化 */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #CBD5E1; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #94A3B8; }

/* ==================== 动画关键帧 ==================== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.95); }
  to   { opacity: 1; transform: scale(1); }
}
@keyframes bgFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50%      { transform: translateY(-10px) scale(1.02); }
}

/* ==================== 认证页面布局 (login/register/forgot) ==================== */
.auth-body {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
  background-size: 400% 400%;
  animation: gradientShift 8s ease infinite;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

@keyframes gradientShift {
  0%   { background-position: 0 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0 50%; }
}

/* 背景装饰圆 */
.auth-body::before {
  content: '';
  position: absolute;
  width: 400px; height: 400px;
  border-radius: 50%;
  background: rgba(255,255,255,0.06);
  top: -100px; right: -100px;
  animation: bgFloat 6s ease-in-out infinite;
}
.auth-body::after {
  content: '';
  position: absolute;
  width: 300px; height: 300px;
  border-radius: 50%;
  background: rgba(255,255,255,0.04);
  bottom: -80px; left: -60px;
  animation: bgFloat 8s ease-in-out infinite reverse;
}

.auth-card {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl), 0 0 0 1px rgba(255,255,255,0.3);
  padding: 48px 40px;
  position: relative;
  z-index: 1;
  animation: scaleIn 0.5s ease-out;
  flex-shrink: 0;
  margin: 0 auto;
}

/* 认证页包裹层：填充宽度，让卡片在窄屏时也能撑满 */
.auth-wrapper {
  width: 100%;
  max-width: 100%;
}

.auth-card .logo-icon {
  width: 56px; height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 20px;
  font-size: 28px;
  color: #fff;
  box-shadow: 0 8px 24px rgba(108,99,255,0.3);
}

.auth-card h2 {
  text-align: center;
  color: var(--text-primary);
  margin-bottom: 6px;
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.auth-card .subtitle {
  text-align: center;
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 32px;
}

/* ==================== 应用页面布局 ==================== */
.app-body {
  background: linear-gradient(180deg, #F8FAFC 0%, #F0F2F8 100%);
  min-height: 100vh;
}

.navbar {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  padding: 0 32px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: 0 2px 16px rgba(102,126,234,0.25);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
}
.navbar-primary { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); }
.navbar-admin { background: linear-gradient(135deg, #e74c3c 0%, #c0392b 100%); box-shadow: 0 2px 16px rgba(231,76,60,0.25); }

.navbar .brand {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.5px;
  display: flex; align-items: center; gap: 10px;
}
.navbar .brand::before {
  content: '🎓';
  font-size: 22px;
}

.navbar .user-info {
  display: flex; align-items: center; gap: 16px; font-size: 14px;
}
.navbar .user-info a {
  color: rgba(255,255,255,0.9);
  padding: 6px 16px;
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 20px;
  font-size: 13px;
  transition: all var(--transition-fast);
  backdrop-filter: blur(4px);
}
.navbar .user-info a:hover {
  background: rgba(255,255,255,0.18);
  border-color: rgba(255,255,255,0.5);
  transform: translateY(-1px);
}

.main {
  max-width: 1000px;
  margin: 32px auto;
  padding: 0 24px;
  animation: fadeInUp 0.4s ease-out;
}

.form-group { margin-bottom: 20px; }
.form-group label {
  display: block;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: 0.3px;
  text-transform: uppercase;
}
.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 15px;
  outline: none;
  transition: all var(--transition-fast);
  background: var(--bg-white);
  color: var(--text-primary);
  font-family: inherit;
}
.form-group input:hover,
.form-group textarea:hover,
.form-group select:hover {
  border-color: #CBD5E1;
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(108,99,255,0.12);
}
.form-group input::placeholder,
.form-group textarea::placeholder { color: var(--text-muted); }
.form-group .hint { font-size: 12px; color: var(--text-muted); margin-top: 6px; }

/* ==================== 按钮 ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  padding: 10px 24px;
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
  letter-spacing: 0.3px;
  white-space: nowrap;
}
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none !important; }

.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  box-shadow: 0 4px 14px rgba(108,99,255,0.35);
}
.btn-primary:hover:not(:disabled) {
  box-shadow: 0 6px 20px rgba(108,99,255,0.45);
  transform: translateY(-1px);
}

.btn-secondary {
  background: #F1F5F9;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}
.btn-secondary:hover { background: #E2E8F0; color: var(--text-primary); }
.btn-secondary.active {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(108,99,255,0.35);
}

.btn-danger {
  background: linear-gradient(135deg, var(--danger), #DC2626);
  color: #fff;
  box-shadow: 0 4px 14px rgba(239,68,68,0.3);
}
.btn-danger:hover:not(:disabled) {
  box-shadow: 0 6px 20px rgba(239,68,68,0.4);
  transform: translateY(-1px);
}

.btn-block { width: 100%; padding: 14px; font-size: 16px; border-radius: 12px; }
.btn-sm { padding: 6px 14px; font-size: 12px; border-radius: 6px; }

/* 按钮波纹效果 */
.btn::after {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  width: 0; height: 0;
  border-radius: 50%;
  background: rgba(255,255,255,0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}
.btn:active::after {
  width: 300px; height: 300px;
}

/* ==================== 消息提示 ==================== */
.error-msg, .success-msg, .info-banner {
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
  animation: fadeInUp 0.3s ease-out;
}
.error-msg {
  background: #FEF2F2; border: 1px solid #FECACA; color: #DC2626;
}
.success-msg {
  background: #ECFDF5; border: 1px solid #A7F3D0; color: #059669;
}
.info-banner {
  background: #EFF6FF; border: 1px solid #BFDBFE; color: #2563EB;
}

/* ==================== 底部链接 ==================== */
.link {
  text-align: center;
  margin-top: 24px;
  font-size: 13px;
  color: var(--text-muted);
}
.link a {
  color: var(--primary);
  font-weight: 600;
  transition: color var(--transition-fast);
}
.link a:hover { color: var(--primary-dark); }

/* ==================== 表格 ==================== */
.table-wrap {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-color);
}

/* ==================== 空状态 ==================== */
.empty-state {
  text-align: center;
  padding: 64px 24px;
  color: var(--text-muted);
}
.empty-state .icon {
  width: 64px; height: 64px;
  margin: 0 auto 20px;
  background: #F1F5F9;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
}
.empty-state h3 { font-size: 16px; color: var(--text-secondary); margin-bottom: 8px; }
.empty-state p { font-size: 14px; color: var(--text-muted); }
.empty-msg { text-align: center; color: var(--text-muted); padding: 40px; font-size: 14px; }

/* ==================== 标签页 ==================== */
.tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 0;
  background: #F1F5F9;
  border-radius: 12px;
  padding: 4px;
  width: fit-content;
}
.tab {
  padding: 10px 24px;
  background: transparent;
  border: none;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: 9px;
  transition: all var(--transition-fast);
}
.tab:hover { color: var(--text-primary); }
.tab.active {
  background: #fff;
  color: var(--primary);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

/* ==================== 徽章 ==================== */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.3px;
}
.badge-success { background: #D1FAE5; color: #065F46; }
.badge-muted { background: #F1F5F9; color: #64748B; }

/* ==================== 模态框 ==================== */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(15,23,42,0.5);
  backdrop-filter: blur(4px);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  animation: fadeIn 0.2s ease-out;
}
.modal-overlay.show { display: flex; }
.modal {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px;
  width: 420px;
  max-width: 92%;
  box-shadow: var(--shadow-xl);
  animation: scaleIn 0.25s ease-out;
}
.modal h3 { font-size: 18px; font-weight: 700; margin-bottom: 12px; color: var(--text-primary); }
.modal p { font-size: 13px; color: var(--text-muted); margin-bottom: 20px; line-height: 1.7; }
.modal input {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-size: 14px;
  margin-bottom: 20px;
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.modal input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(108,99,255,0.12);
}
.modal .btn-group { display: flex; gap: 12px; justify-content: flex-end; }
.modal .btn-group .btn { min-width: 80px; }

/* ==================== Toast通知 ==================== */
.toast-container {
  position: fixed;
  top: 24px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 10px;
  pointer-events: none;
}
.toast {
  padding: 14px 20px;
  border-radius: 12px;
  color: #fff;
  font-size: 14px;
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  animation: toastSlideIn 0.3s ease-out;
  max-width: 360px;
  pointer-events: auto;
  display: flex; align-items: center; gap: 8px;
}
.toast.success { background: linear-gradient(135deg, #10B981, #059669); }
.toast.error { background: linear-gradient(135deg, #EF4444, #DC2626); }
.toast.info { background: linear-gradient(135deg, #3B82F6, #2563EB); }
.toast.warning { background: linear-gradient(135deg, #F59E0B, #D97706); }

@keyframes toastSlideIn {
  from { opacity: 0; transform: translateX(80px); }
  to   { opacity: 1; transform: translateX(0); }
}

/* ==================== 选择框美化 ==================== */
select {
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M6 8L1 3h10z' fill='%2394A3B8'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px !important;
}

/* ==================== 分割线 ==================== */
.divider {
  border: none;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color), transparent);
  margin: 24px 0;
}

/* ==================== 工具类 ==================== */
.text-center { text-align: center; }
.text-muted { color: var(--text-muted); }
.text-primary { color: var(--primary); }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.flex-center { display: flex; align-items: center; justify-content: center; }

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
  .navbar { padding: 0 16px; }
  .navbar .brand { font-size: 15px; }
  .navbar .user-info { gap: 8px; }
  .main { padding: 0 16px; margin: 20px auto; }
}
/* 窄屏：卡片撑满宽度，仅保留 8px 边距，自居中 */
@media (max-width: 480px) {
  .auth-card {
    width: calc(100% - 16px) !important;
    max-width: 100%;
    margin-left: auto;
    margin-right: auto;
    padding: 24px 16px;
    border-radius: var(--radius-md);
  }
  .navbar { padding: 0 12px; }
  .main { padding: 0 10px; margin: 12px auto; }
}