/* ==========================================================================
   奥邦品牌设计 - 公共样式系统
   AOBANG BRAND DESIGN SYSTEM
   ========================================================================== */

/* ---------- 设计令牌 ---------- */
:root {
  /* 色彩 - 大地暖调 */
  --color-bg: #FAF7F2;            /* 主背景 米白 */
  --color-bg-alt: #F0E9DD;        /* 副背景 奶油 */
  --color-bg-deep: #2C2620;       /* 深背景 焦咖 */
  --color-surface: #FFFFFF;       /* 卡片表面 */
  --color-cream: #F5EFE6;         /* 奶油色 */
  --color-paper: #EFE7D8;         /* 纸质纹理色 */

  /* 主色 */
  --color-ink: #1A1714;           /* 主文字 墨黑 */
  --color-ink-soft: #2C2620;      /* 副文字 焦咖 */
  --color-text: #3A322C;         /* 段落文字 */
  --color-muted: #6B5D52;        /* 灰褐 */
  --color-line: #D8CFC0;         /* 分割线 */

  /* 点缀 */
  --color-gold: #B8935C;         /* 古铜金 */
  --color-gold-deep: #8E6F43;    /* 深金 */
  --color-orange: #D4814E;       /* 暖橙 */
  --color-terracotta: #B85C38;   /* 赭红 */
  --color-sage: #7B8B6F;         /* 苔藓绿 */

  /* 状态色 */
  --color-success: #5B7553;
  --color-warning: #C8954B;

  /* 字体 */
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-display: "Cormorant Garamond", "Noto Serif SC", serif;

  /* 字号 */
  --fs-xs: 12px;
  --fs-sm: 14px;
  --fs-base: 16px;
  --fs-md: 18px;
  --fs-lg: 20px;
  --fs-xl: 24px;
  --fs-2xl: 32px;
  --fs-3xl: 42px;
  --fs-4xl: 56px;
  --fs-5xl: 76px;
  --fs-6xl: 104px;

  /* 字距 */
  --tracking-tight: -0.02em;
  --tracking-normal: 0;
  --tracking-wide: 0.05em;
  --tracking-wider: 0.15em;
  --tracking-widest: 0.3em;

  /* 间距 */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;
  --space-20: 80px;
  --space-24: 96px;
  --space-32: 128px;

  /* 圆角 */
  --radius-sm: 2px;
  --radius-md: 6px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  --radius-full: 999px;

  /* 阴影 */
  --shadow-xs: 0 1px 2px rgba(44, 38, 32, 0.04);
  --shadow-sm: 0 2px 8px rgba(44, 38, 32, 0.06);
  --shadow-md: 0 4px 24px rgba(44, 38, 32, 0.08);
  --shadow-lg: 0 12px 48px rgba(44, 38, 32, 0.12);
  --shadow-xl: 0 24px 64px rgba(44, 38, 32, 0.16);

  /* 容器 */
  --container-max: 1440px;
  --container-pad: clamp(20px, 4vw, 80px);

  /* 动效 */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --duration-fast: 200ms;
  --duration-base: 400ms;
  --duration-slow: 800ms;
}

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

html {
  font-size: var(--fs-base);
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img, svg, video {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

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

ul, ol {
  list-style: none;
}

::selection {
  background: var(--color-gold);
  color: var(--color-bg);
}

/* ---------- 排版 ---------- */
.h-display {
  font-family: var(--font-serif);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: var(--tracking-tight);
  color: var(--color-ink);
}

.h1 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(40px, 5.6vw, 84px);
  line-height: 1.08;
  letter-spacing: var(--tracking-tight);
  color: var(--color-ink);
}

.h2 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(32px, 3.8vw, 56px);
  line-height: 1.15;
  letter-spacing: var(--tracking-tight);
  color: var(--color-ink);
}

.h3 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(24px, 2.4vw, 36px);
  line-height: 1.25;
  letter-spacing: var(--tracking-normal);
  color: var(--color-ink);
}

.h4 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(20px, 1.8vw, 26px);
  line-height: 1.3;
  color: var(--color-ink);
}

.h5 {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: var(--fs-md);
  line-height: 1.4;
  color: var(--color-ink);
}

.lead {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(18px, 1.6vw, 22px);
  line-height: 1.6;
  color: var(--color-muted);
  font-style: italic;
}

.body-lg {
  font-size: var(--fs-md);
  line-height: 1.75;
  color: var(--color-text);
}

.body {
  font-size: var(--fs-base);
  line-height: 1.7;
  color: var(--color-text);
}

.body-sm {
  font-size: var(--fs-sm);
  line-height: 1.65;
  color: var(--color-muted);
}

.eyebrow {
  font-family: var(--font-sans);
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: var(--tracking-widest);
  text-transform: uppercase;
  color: var(--color-gold-deep);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.eyebrow::before {
  content: "";
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--color-gold-deep);
}

.text-muted { color: var(--color-muted); }
.text-gold { color: var(--color-gold-deep); }

/* ---------- 容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding-left: var(--container-pad);
  padding-right: var(--container-pad);
}

.container-narrow {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding-left: var(--container-pad);
  padding-right: var(--container-pad);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  font-family: var(--font-sans);
  font-size: var(--fs-sm);
  font-weight: 500;
  letter-spacing: var(--tracking-wide);
  padding: 14px 32px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--duration-base) var(--ease-out);
  white-space: nowrap;
  user-select: none;
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--color-ink);
  color: var(--color-bg);
  border: 1px solid var(--color-ink);
}

.btn-primary:hover {
  background: var(--color-ink-soft);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

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

.btn-gold {
  background: var(--color-gold);
  color: var(--color-bg);
  border: 1px solid var(--color-gold);
}

.btn-gold:hover {
  background: var(--color-gold-deep);
  border-color: var(--color-gold-deep);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-ghost {
  background: transparent;
  color: var(--color-ink);
  border: 1px solid transparent;
  padding-left: 0;
  padding-right: 0;
  border-radius: 0;
}

.btn-ghost::after {
  content: "→";
  transition: transform var(--duration-base) var(--ease-out);
}

.btn-ghost:hover::after {
  transform: translateX(8px);
}

.btn-large {
  padding: 18px 42px;
  font-size: var(--fs-base);
}

.btn-arrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-weight: 500;
  letter-spacing: var(--tracking-wide);
  position: relative;
}

.btn-arrow .arrow {
  display: inline-block;
  transition: transform var(--duration-base) var(--ease-out);
}

.btn-arrow:hover .arrow {
  transform: translateX(6px);
}

/* ---------- 章节 ---------- */
.section {
  padding-top: clamp(80px, 12vw, 160px);
  padding-bottom: clamp(80px, 12vw, 160px);
  position: relative;
}

.section-sm {
  padding-top: clamp(60px, 8vw, 100px);
  padding-bottom: clamp(60px, 8vw, 100px);
}

.section-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-line), transparent);
  margin: 0 var(--container-pad);
}

/* ---------- 卡片 ---------- */
.card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: all var(--duration-base) var(--ease-out);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

/* ---------- 徽章 ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: var(--fs-xs);
  font-weight: 500;
  letter-spacing: var(--tracking-wide);
  border-radius: var(--radius-full);
  background: var(--color-bg-alt);
  color: var(--color-ink-soft);
}

.badge-gold {
  background: rgba(184, 147, 92, 0.12);
  color: var(--color-gold-deep);
}

.badge-outline {
  background: transparent;
  border: 1px solid var(--color-line);
  color: var(--color-muted);
}

/* ---------- 分割线 ---------- */
.divider {
  width: 100%;
  height: 1px;
  background: var(--color-line);
  border: none;
}

/* ---------- 装饰 ---------- */
.deco-line {
  display: inline-block;
  width: 48px;
  height: 1px;
  background: var(--color-gold-deep);
  vertical-align: middle;
}

.bg-paper {
  background-color: var(--color-paper);
  background-image:
    radial-gradient(circle at 1px 1px, rgba(44, 38, 32, 0.04) 1px, transparent 0);
  background-size: 24px 24px;
}

/* ---------- 动画 ---------- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(-16px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes marquee {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

@keyframes rotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 100ms; }
.reveal-delay-2 { transition-delay: 200ms; }
.reveal-delay-3 { transition-delay: 300ms; }
.reveal-delay-4 { transition-delay: 400ms; }

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

/* ---------- 工具类 ---------- */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0 !important; }
.mb-0 { margin-bottom: 0 !important; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.grid { display: grid; }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1024px) {
  .grid-cols-3, .grid-cols-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .grid-cols-2, .grid-cols-3, .grid-cols-4 { grid-template-columns: 1fr; }
}

/* ---------- 链接下划线动画 ---------- */
.link-underline {
  position: relative;
  display: inline-block;
  padding-bottom: 2px;
}

.link-underline::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform-origin: right;
  transform: scaleX(0);
  transition: transform var(--duration-base) var(--ease-out);
}

.link-underline:hover::after {
  transform-origin: left;
  transform: scaleX(1);
}