/* ========================================
   base.css — 重置、设计令牌、基础排版
   ======================================== */

/* ---------- 设计令牌 ---------- */
:root {
  /* 色彩 */
  --color-ink: #0E0E0E;
  --color-ink-soft: #1A1A1A;
  --color-ivory: #F4F1EA;
  --color-ivory-dim: #E8E3D8;
  --color-paper: #FBF9F4;
  --color-accent: #2DD4BF;
  --color-accent-dark: #14B8A6;
  --color-accent-glow: rgba(45, 212, 191, 0.25);
  --color-stone: #8C8A85;
  --color-stone-light: #B8B5AE;
  --color-line: rgba(244, 241, 234, 0.12);
  --color-line-dark: rgba(14, 14, 14, 0.1);

  /* 字体族 */
  --font-display: "Cormorant Garamond", "Songti SC", "STSong", serif;
  --font-body: "Manrope", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", "Consolas", monospace;

  /* 字号 */
  --fs-hero: clamp(4.5rem, 14vw, 16rem);
  --fs-display: clamp(2.5rem, 6vw, 5.5rem);
  --fs-h2: clamp(2rem, 4vw, 3.25rem);
  --fs-h3: clamp(1.25rem, 2vw, 1.75rem);
  --fs-body: 1rem;
  --fs-small: 0.8125rem;
  --fs-micro: 0.6875rem;

  /* 间距 */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 8rem;
  --space-2xl: 12rem;

  /* 容器 */
  --container: 1440px;
  --container-wide: 1920px;
  --gutter: clamp(1.5rem, 4vw, 4rem);

  /* 过渡 */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --transition-base: 0.6s var(--ease-out);
  --transition-fast: 0.3s var(--ease-out);

  /* 圆角 */
  --radius: 2px;
}

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

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

body {
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.65;
  color: var(--color-ivory);
  background-color: var(--color-ink);
  overflow-x: hidden;
}

/* ---------- 排版基础 ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: -0.01em;
}

p {
  line-height: 1.7;
}

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

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

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

ul, ol {
  list-style: none;
}

/* ---------- 通用工具类 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.container-wide {
  width: 100%;
  max-width: var(--container-wide);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* 等宽标签 */
.mono-label {
  font-family: var(--font-mono);
  font-size: var(--fs-micro);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-stone-light);
}

/* 强调色文本 */
.accent {
  color: var(--color-accent);
}

/* 下划线链接按钮 */
.link-btn {
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding-bottom: 4px;
}

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

.link-btn:hover::after {
  transform-origin: left;
  transform: scaleX(0);
  animation: linkRedraw 0.6s var(--ease-out) 0.3s forwards;
}

@keyframes linkRedraw {
  from { transform-origin: left; transform: scaleX(0); }
  to { transform-origin: left; transform: scaleX(1); }
}

/* 方形边框按钮 */
.btn-outline {
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border: 1px solid var(--color-line);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn-outline::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--color-accent);
  transform: translateY(101%);
  transition: transform var(--transition-base);
  z-index: -1;
}

.btn-outline:hover {
  border-color: var(--color-accent);
  color: var(--color-ivory);
}

.btn-outline:hover::before {
  transform: translateY(0);
}

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

::-webkit-scrollbar-track {
  background: var(--color-ink);
}

::-webkit-scrollbar-thumb {
  background: var(--color-stone);
}

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

/* ---------- 选区 ---------- */
::selection {
  background: var(--color-accent);
  color: var(--color-ivory);
}

/* ---------- 噪点纹理叠加 ---------- */
.noise-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9998;
  opacity: 0.035;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- 滚动渐入动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 1s var(--ease-out), transform 1s var(--ease-out);
}

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

.reveal-stagger > * {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s var(--ease-out), transform 0.8s var(--ease-out);
}

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

.reveal-stagger.is-visible > *:nth-child(1) { transition-delay: 0s; }
.reveal-stagger.is-visible > *:nth-child(2) { transition-delay: 0.1s; }
.reveal-stagger.is-visible > *:nth-child(3) { transition-delay: 0.2s; }
.reveal-stagger.is-visible > *:nth-child(4) { transition-delay: 0.3s; }
.reveal-stagger.is-visible > *:nth-child(5) { transition-delay: 0.4s; }
.reveal-stagger.is-visible > *:nth-child(6) { transition-delay: 0.5s; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  :root {
    --space-xl: 6rem;
    --space-2xl: 8rem;
  }
}

@media (max-width: 768px) {
  :root {
    --space-lg: 3rem;
    --space-xl: 4rem;
    --space-2xl: 6rem;
  }
}

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