/* ===== 全局重置与基础样式 ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #6366F1;
  --primary-dark: #4F46E5;
  --secondary: #8B5CF6;
  --bg-dark: #0F0F1A;
  --bg-card: #1A1A2E;
  --bg-input: #16162A;
  --text-primary: #F8F9FA;
  --text-secondary: #A0A0B0;
  --border-color: #2A2A40;
  --success: #10B981;
  --error: #EF4444;
  --warning: #F59E0B;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --transition: 0.3s ease;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  background: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: var(--transition);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  box-shadow: 0 4px 16px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(99, 102, 241, 0.6);
}

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-full {
  width: 100%;
  justify-content: center;
  padding: 14px 24px;
  font-size: 16px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

/* ===== 表单消息 ===== */
.form-message {
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  margin-bottom: 16px;
  display: none;
}

.form-message.error {
  display: block;
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: var(--error);
}

.form-message.success {
  display: block;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: var(--success);
}

.form-message.info {
  display: block;
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.3);
  color: var(--primary);
}

/* ===== Toast 通知 ===== */
#toast-container {
  position: fixed;
  top: 24px;
  right: 24px;
  z-index: 10000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  animation: toastIn 0.3s ease;
  box-shadow: var(--shadow);
  max-width: 320px;
}

.toast-success {
  background: var(--success);
  color: #fff;
}

.toast-error {
  background: var(--error);
  color: #fff;
}

.toast-info {
  background: var(--primary);
  color: #fff;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateX(100px); }
  to { opacity: 1; transform: translateX(0); }
}

/* ===== 页面切换 ===== */
.page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
}

.page.hidden {
  display: none;
}

#page-home.hidden {
  display: none;
}