/* ==========================================
   乐达助手 - 设计系统基础
   ========================================== */

/* CSS 变量系统 */
:root {
  --bg-primary: #FEFDF9;
  --bg-warm: #FFF5EE;
  --bg-cool: #F0F7FF;
  --accent: #FF6B35;
  --accent-hover: #E55A2B;
  --text-primary: #1A1A2E;
  --text-secondary: #6B7280;
  --stroke: #2D2D2D;
  --shadow-float: 0 8px 32px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.12);
  --radius-pill: 50px;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 8px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 100px;
  font-size: 16px;
}

body {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-weight: 400;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 字体引入（备用，CDN在HTML中引入） */
/* Google Fonts: Noto Sans SC */

/* 标题样式 */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

/* 链接 */
a {
  color: inherit;
  text-decoration: none;
  transition: color 0.25s ease;
}

/* 图片 */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* 列表 */
ul, ol {
  list-style: none;
}

/* 按钮基础 */
button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* 工具类 */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

.section-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.7;
}

.accent-text {
  color: var(--accent);
}

/* 按钮样式 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
}

.btn-primary {
  background-color: var(--accent);
  color: #fff;
  box-shadow: 0 4px 16px rgba(255, 107, 53, 0.35);
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(255, 107, 53, 0.45);
}

.btn-primary:hover .btn-arrow {
  transform: translateX(4px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border: 2px solid var(--text-primary);
}

.btn-secondary:hover {
  background-color: var(--text-primary);
  color: var(--bg-primary);
  transform: translateY(-2px);
}

.btn-arrow {
  transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 隐藏类 */
.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;
}

/* 减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}