/* ========================================
   Base Styles - 重置 + 全局基础
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;600;700&family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  color: var(--frame-text);
  background: var(--frame-bg);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

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

a:hover {
  color: var(--accent-primary-hover);
}

img {
  max-width: 100%;
  display: block;
}

button {
  cursor: pointer;
  font-family: inherit;
  font-size: inherit;
  border: none;
  background: none;
  color: inherit;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

ul, ol {
  list-style: none;
}

/* === 滚动条 === */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--frame-border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}

/* === 工具类 === */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.hidden {
  display: none !important;
}

.fade-in {
  animation: fadeIn var(--transition-normal) ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* === Toast 通知 === */
.toast-container {
  position: fixed;
  top: var(--spacing-lg);
  right: var(--spacing-lg);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.toast {
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  color: #fff;
  font-size: 0.9rem;
  animation: slideInRight 300ms ease-out;
  box-shadow: var(--shadow-md);
}

.toast.success { background: var(--accent-green); }
.toast.error { background: var(--accent-red); }
.toast.info { background: var(--accent-primary); }
.toast.warning { background: var(--accent-orange); }

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