/* ====== CSS 变量 ====== */
:root {
  --primary: #1a56db;
  --primary-dark: #1e40af;
  --primary-light: #e8f0fe;
  --success: #059669;
  --success-bg: #ecfdf5;
  --warning: #d97706;
  --warning-bg: #fffbeb;
  --danger: #dc2626;
  --danger-bg: #fef2f2;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,.1);
  --shadow-lg: 0 10px 30px rgba(0,0,0,.12);
  --safe-bottom: env(safe-area-inset-bottom, 16px);
}

/* ====== 基础重置 ====== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;-webkit-text-size-adjust:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--gray-50);color:var(--gray-800);line-height:1.6;
  min-height:100vh;-webkit-font-smoothing:antialiased;
}
a{color:var(--primary);text-decoration:none}
img{max-width:100%;display:block}
button,input,select,textarea{font:inherit;color:inherit}
button{touch-action:manipulation}

/* ====== 容器 ====== */
.container{
  max-width:480px;margin:0 auto;padding:0 16px;
  min-height:100vh;display:flex;flex-direction:column;
}

/* ====== 顶部导航栏 ====== */
.navbar{
  position:sticky;top:0;z-index:100;
  background:rgba(255,255,255,.85);backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid var(--gray-200);
  padding:0 16px;height:52px;
  display:flex;align-items:center;justify-content:space-between;
}
.navbar .logo{font-size:17px;font-weight:700;color:var(--gray-900)}
.navbar .back-btn{
  width:36px;height:36px;border-radius:50%;border:none;background:var(--gray-100);
  display:flex;align-items:center;justify-content:center;font-size:18px;
  cursor:pointer;color:var(--gray-600);
}
.navbar .back-btn:active{background:var(--gray-200)}

/* ====== 页面主体 ====== */
.page{padding:20px 0;flex:1}

/* ====== 卡片 ====== */
.card{
  background:#fff;border-radius:var(--radius);
  box-shadow:var(--shadow);padding:20px;margin-bottom:16px;
}
.card-title{font-size:16px;font-weight:600;margin-bottom:12px}

/* ====== 按钮 ====== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  font-size:15px;font-weight:500;padding:11px 24px;border-radius:var(--radius-sm);
  border:none;cursor:pointer;transition:all .15s;user-select:none;
  min-height:44px;
}
.btn:active{transform:scale(.97)}
.btn:disabled{opacity:.5;pointer-events:none}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark)}
.btn-success{background:var(--success);color:#fff}
.btn-outline{
  background:#fff;color:var(--gray-700);border:1.5px solid var(--gray-300);
}
.btn-outline:hover{background:var(--gray-50)}
.btn-danger{background:var(--danger);color:#fff}
.btn-block{width:100%}
.btn-lg{font-size:17px;padding:14px 28px;border-radius:var(--radius)}
.btn-sm{font-size:13px;padding:6px 14px;min-height:auto}

/* ====== 表单 ====== */
.input-group{margin-bottom:14px}
.input-group label{display:block;font-size:14px;font-weight:500;margin-bottom:4px;color:var(--gray-700)}
.input,.select{
  width:100%;padding:10px 14px;border:1.5px solid var(--gray-300);
  border-radius:var(--radius-sm);font-size:15px;background:#fff;
  transition:border-color .15s;outline:none;
}
.input:focus,.select:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-light)}

/* ====== Toast 提示 ====== */
.toast-container{
  position:fixed;top:20px;left:50%;transform:translateX(-50%);
  z-index:9999;display:flex;flex-direction:column;gap:8px;
  width:calc(100% - 32px);max-width:400px;pointer-events:none;
}
.toast{
  padding:12px 16px;border-radius:var(--radius-sm);
  font-size:14px;box-shadow:var(--shadow-md);
  animation:toastIn .25s ease;pointer-events:auto;
  display:flex;align-items:center;gap:8px;
}
.toast-success{background:#065f46;color:#fff}
.toast-error{background:#991b1b;color:#fff}
.toast-info{background:var(--primary-dark);color:#fff}
@keyframes toastIn{from{opacity:0;transform:translateY(-12px)}to{opacity:1;transform:translateY(0)}}

/* ====== Modal 弹窗 ====== */
.modal-overlay{
  display:none;position:fixed;inset:0;z-index:200;
  background:rgba(0,0,0,.45);justify-content:center;align-items:flex-end;
}
.modal-overlay.show{display:flex}
.modal{
  background:#fff;border-radius:var(--radius) var(--radius) 0 0;
  width:100%;max-width:480px;max-height:85vh;overflow-y:auto;
  padding:24px;animation:modalUp .3s ease;
}
@keyframes modalUp{from{transform:translateY(100%)}to{transform:translateY(0)}}
.modal-title{font-size:18px;font-weight:600;margin-bottom:16px;text-align:center}

/* ====== 底部导航 ====== */
.bottom-nav{
  position:sticky;bottom:0;background:rgba(255,255,255,.9);
  backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
  border-top:1px solid var(--gray-200);
  display:flex;justify-content:space-around;
  padding:6px 0 var(--safe-bottom);
}
.bottom-nav a{
  display:flex;flex-direction:column;align-items:center;gap:2px;
  font-size:11px;color:var(--gray-400);padding:4px 12px;
  transition:color .15s;text-decoration:none;
}
.bottom-nav a.active{color:var(--primary)}
.bottom-nav a .nav-icon{font-size:22px}

/* ====== 加载动画 ====== */
.spinner{
  width:28px;height:28px;border:3px solid var(--gray-200);
  border-top-color:var(--primary);border-radius:50%;
  animation:spin .6s linear infinite;margin:0 auto;
}
@keyframes spin{to{transform:rotate(360deg)}}
.loading-screen{
  display:flex;flex-direction:column;align-items:center;
  justify-content:center;gap:14px;padding:60px 0;color:var(--gray-500);
}

/* ====== 空状态 ====== */
.empty-state{
  text-align:center;padding:60px 20px;color:var(--gray-400);
}
.empty-state .empty-icon{font-size:48px;margin-bottom:12px}
.empty-state p{font-size:14px}

/* ====== 套餐选择卡片 ====== */
.plan-option{
  display:block;position:relative;
  border:2px solid var(--gray-200);border-radius:var(--radius);
  padding:16px;cursor:pointer;transition:all .15s;
}
.plan-option.selected{border-color:var(--primary);background:var(--primary-light)}
.plan-option:hover:not(.selected){border-color:var(--gray-300)}
.plan-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:6px}
.plan-name{font-size:16px;font-weight:600}
.plan-price{font-size:20px;font-weight:700;color:var(--danger)}
.plan-desc{font-size:13px;color:var(--gray-500);margin-bottom:8px}
.plan-features{list-style:none;font-size:12px;color:var(--gray-600);display:flex;flex-direction:column;gap:3px;padding-left:4px}
.plan-features li{display:flex;align-items:center;gap:4px}
.plan-badge{
  position:absolute;top:-1px;right:-1px;
  background:var(--primary);color:#fff;font-size:11px;
  padding:3px 10px;border-radius:0 var(--radius) 0 var(--radius);
  font-weight:500;
}

/* ====== 支付方式选择 ====== */
.pay-method{
  display:flex;align-items:center;gap:14px;
  padding:14px 16px;border:2px solid var(--gray-200);
  border-radius:var(--radius-sm);cursor:pointer;transition:all .15s;
}
.pay-method.selected{border-color:var(--primary);background:var(--primary-light)}
.pay-method.selected .check-mark{display:inline!important}
.pay-method:hover:not(.selected){border-color:var(--gray-300)}

/* ====== 订单卡片 & 状态标签 ====== */
.order-card:active{background:var(--gray-50)}
.status-pending{color:var(--warning);font-size:12px;font-weight:500}
.status-paid{color:var(--primary);font-size:12px;font-weight:500}
.status-detecting{color:var(--primary);font-size:12px;font-weight:500}
.status-done{color:var(--success);font-size:12px;font-weight:500}
.status-failed{color:var(--danger);font-size:12px;font-weight:500}

/* ====== 安全区适配 ====== */
@supports(padding-bottom:env(safe-area-inset-bottom)){
  .page{padding-bottom:calc(20px + env(safe-area-inset-bottom))}
}

/* ====== 响应式：桌面端居中 ====== */
@media(min-width:768px){
  body{background:#e5e7eb}
  .container{box-shadow:0 0 40px rgba(0,0,0,.1);background:#fff;min-height:100vh}
}