/* ============================================================
   Ink Blog · main.css
   主样式：变量、排版、布局、留白哲学
   ============================================================ */

/* ---------- 设计变量：墨分五色 + 宣纸 + 朱砂 ---------- */
:root {
  /* 墨色五阶 */
  --ink-jiao:  #0d0d0d;   /* 焦墨 - 最深 */
  --ink-nong:  #1a1a1a;   /* 浓墨 */
  --ink-zhong: #3d3d3d;   /* 重墨 */
  --ink-dan:   #6b6b6b;   /* 淡墨 */
  --ink-qing:  #a8a29a;   /* 清墨 - 最淡 */

  /* 宣纸色阶 */
  --paper:      #f4ecdd;  /* 主宣纸色 */
  --paper-light: #faf5ea;
  --paper-dark: #e8dcc4;
  --paper-aged: #ddc9a3;  /* 旧宣纸 */

  /* 朱砂 */
  --seal:       #9c2a2a;
  --seal-light: #c44545;
  --seal-glow:  rgba(156, 42, 42, 0.35);

  /* 辅助 */
  --gold:       #b08d3c;
  --bamboo:     #5a6b4a;

  /* 字号系统（1.25 比例） */
  --fs-xs:   0.75rem;
  --fs-sm:   0.875rem;
  --fs-base: 1rem;
  --fs-md:   1.125rem;
  --fs-lg:   1.5rem;
  --fs-xl:   2rem;
  --fs-2xl:  2.75rem;
  --fs-3xl:  4rem;
  --fs-hero: 6rem;

  /* 间距节奏（东方留白） */
  --sp-1: 0.5rem;
  --sp-2: 1rem;
  --sp-3: 1.5rem;
  --sp-4: 2.5rem;
  --sp-5: 4rem;
  --sp-6: 6rem;
  --sp-7: 9rem;

  /* 缓动：运笔的提按顿挫 */
  --ease-ink:      cubic-bezier(0.22, 0.61, 0.36, 1);
  --ease-brush:    cubic-bezier(0.65, 0, 0.35, 1);
  --ease-settle:   cubic-bezier(0.16, 1, 0.3, 1);

  /* 字体 */
  --font-kai:      'Ma Shan Zheng', 'STKaiti', 'KaiTi', '楷体', cursive;       /* 书法/标题 */
  --font-song:     'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', 'STSong', '宋体', serif; /* 正文宋体 */
  --font-latin:    'Cormorant Garamond', 'Times New Roman', serif;              /* 英文 */

  /* 尺寸 */
  --reading-width: 42rem;
  --nav-height: 4.5rem;
}

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

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

body {
  font-family: var(--font-song);
  color: var(--ink-nong);
  background: var(--paper);
  line-height: 1.8;
  letter-spacing: 0.04em;
  overflow-x: hidden;
  cursor: none; /* 自定义毛笔鼠标 */
  min-height: 100vh;
}

/* 隐藏滚动条美化 */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--paper-dark); }
::-webkit-scrollbar-thumb { background: var(--ink-qing); border-radius: 0; }
::-webkit-scrollbar-thumb:hover { background: var(--ink-dan); }

::selection { background: var(--seal); color: var(--paper-light); }

a { color: inherit; text-decoration: none; transition: color .4s var(--ease-ink); }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: none; border: none; background: none; color: inherit; }

/* ---------- 排版 ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-kai);
  font-weight: 400;
  line-height: 1.3;
  color: var(--ink-jiao);
  letter-spacing: 0.06em;
}

.latin, .en { font-family: var(--font-latin); font-style: italic; letter-spacing: 0.02em; }

/* 竖排文字 */
.vertical {
  writing-mode: vertical-rl;
  text-orientation: upright;
  letter-spacing: 0.3em;
}

/* ---------- 宣纸背景纹理（CSS 生成） ---------- */
.paper-bg {
  position: relative;
  background-color: var(--paper);
  background-image:
    /* 细微噪点（纤维感） */
    radial-gradient(circle at 20% 30%, rgba(120, 90, 50, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 80% 70%, rgba(80, 60, 30, 0.05) 0%, transparent 35%),
    radial-gradient(circle at 50% 90%, rgba(140, 100, 60, 0.03) 0%, transparent 50%),
    /* 整体淡淡的旧纸渐变 */
    linear-gradient(135deg, var(--paper-light) 0%, var(--paper) 50%, var(--paper-dark) 100%);
}

/* 宣纸纤维细节层（伪元素叠加） */
.paper-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.5;
  background-image:
    repeating-linear-gradient(97deg, transparent 0, transparent 3px, rgba(120,90,40,0.012) 3px, rgba(120,90,40,0.012) 4px),
    repeating-linear-gradient(3deg, transparent 0, transparent 5px, rgba(80,60,30,0.01) 5px, rgba(80,60,30,0.01) 7px);
  mix-blend-mode: multiply;
}

/* ---------- 全局背景 canvas 层 ---------- */
#ink-canvas {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

/* 页面内容层叠在 canvas 之上 */
.page-wrap {
  position: relative;
  z-index: 2;
}

/* ---------- 布局容器 ---------- */
.container {
  width: min(1200px, 92%);
  margin-inline: auto;
}
.container-narrow {
  width: min(720px, 88%);
  margin-inline: auto;
}
.container-wide {
  width: min(1400px, 94%);
  margin-inline: auto;
}

.section { padding-block: var(--sp-7); }
.section-tight { padding-block: var(--sp-5); }

/* ---------- 印章组件 ---------- */
.seal {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  background: var(--seal);
  color: var(--paper-light);
  font-family: var(--font-kai);
  font-size: 1.1rem;
  letter-spacing: 0;
  line-height: 1;
  border-radius: 4px;
  box-shadow:
    inset 0 0 0 2px rgba(255,255,255,0.15),
    0 0 0 1px var(--seal),
    0 2px 8px var(--seal-glow);
  position: relative;
  text-align: center;
  padding: 4px;
  /* 印章不规则边缘 */
  clip-path: polygon(2% 0, 98% 1%, 100% 3%, 99% 97%, 97% 100%, 3% 99%, 0 97%, 1% 3%);
}
.seal-lg { width: 5rem; height: 5rem; font-size: 1.8rem; }
.seal-sm { width: 2.2rem; height: 2.2rem; font-size: 0.85rem; }
.seal-rect {
  width: auto;
  padding: 0.5rem 1rem;
  border-radius: 2px;
  font-size: 0.95rem;
}

/* 朱砂印泥的斑驳感 */
.seal::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 30% 40%, transparent 0%, transparent 60%, rgba(0,0,0,0.12) 70%),
    radial-gradient(circle at 70% 60%, rgba(255,255,255,0.18) 0%, transparent 30%);
  mix-blend-mode: overlay;
  border-radius: inherit;
}

/* ---------- 按钮组件（书法笔触） ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.8rem 2rem;
  font-family: var(--font-kai);
  font-size: var(--fs-md);
  letter-spacing: 0.15em;
  color: var(--ink-nong);
  background: transparent;
  border: 1px solid var(--ink-nong);
  position: relative;
  overflow: hidden;
  transition: color .5s var(--ease-ink);
  z-index: 1;
}
.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--ink-jiao);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .5s var(--ease-brush);
  z-index: -1;
}
.btn:hover { color: var(--paper-light); }
.btn:hover::before { transform: scaleX(1); }
.btn-seal {
  border-color: var(--seal);
  color: var(--seal);
}
.btn-seal::before { background: var(--seal); }

/* ---------- 文字工具类 ---------- */
.text-center { text-align: center; }
.text-muted { color: var(--ink-dan); }
.text-faint { color: var(--ink-qing); }
.text-seal { color: var(--seal); }
.text-ink { color: var(--ink-jiao); }

.eyebrow {
  font-family: var(--font-latin);
  font-style: italic;
  font-size: var(--fs-sm);
  letter-spacing: 0.3em;
  color: var(--ink-qing);
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 0.8rem;
}
.eyebrow::before, .eyebrow::after {
  content: '';
  width: 2rem;
  height: 1px;
  background: var(--ink-qing);
  opacity: 0.6;
}
.eyebrow.left::after { display: none; }

/* 标题装饰：标题侧的小印章/标记 */
.title-mark {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: var(--sp-3);
}
.title-mark .mark-num {
  font-family: var(--font-latin);
  font-style: italic;
  color: var(--seal);
  font-size: var(--fs-lg);
}

/* ---------- 分隔线（毛笔一横） ---------- */
.brush-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-block: var(--sp-5);
}
.brush-divider::before,
.brush-divider::after {
  content: '';
  height: 1px;
  width: min(120px, 20vw);
  background: linear-gradient(to right, transparent, var(--ink-dan), transparent);
}
.brush-divider .dot {
  width: 6px; height: 6px;
  background: var(--seal);
  border-radius: 50%;
  transform: rotate(45deg);
}

/* ---------- 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 2;
  padding-block: var(--sp-6) var(--sp-4);
  text-align: center;
  color: var(--ink-dan);
  font-size: var(--fs-sm);
  border-top: 1px solid rgba(0,0,0,0.08);
  background: linear-gradient(to bottom, transparent, rgba(232,220,196,0.4));
}
.site-footer .footer-seal {
  margin-bottom: var(--sp-2);
}
.site-footer p { margin-block: var(--sp-1); }

/* ---------- 卡片/纸笺通用 ---------- */
.scroll-card {
  position: relative;
  background:
    linear-gradient(180deg, var(--paper-light) 0%, var(--paper) 100%);
  padding: var(--sp-4);
  box-shadow:
    0 1px 2px rgba(60,40,20,0.08),
    0 8px 24px rgba(60,40,20,0.06);
  transition: transform .6s var(--ease-settle), box-shadow .6s var(--ease-settle);
}
/* 纸笺四角的细微做旧 */
.scroll-card::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 0% 0%, rgba(140,100,60,0.08) 0%, transparent 12%),
    radial-gradient(circle at 100% 100%, rgba(140,100,60,0.08) 0%, transparent 12%);
}

/* ---------- 阅读进度条（毛笔笔触） ---------- */
.reading-progress {
  position: fixed;
  top: 0; left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(to right,
    transparent 0%,
    var(--ink-nong) 8%,
    var(--ink-jiao) 50%,
    var(--ink-dan) 92%,
    transparent 100%);
  z-index: 1000;
  box-shadow: 0 0 6px rgba(0,0,0,0.2);
  transition: width .1s linear;
}
.reading-progress::after {
  content: '';
  position: absolute;
  right: -2px; top: -4px;
  width: 8px; height: 11px;
  background: radial-gradient(circle, var(--ink-jiao) 30%, transparent 70%);
  filter: blur(1px);
}

/* ---------- 可访问性 / 响应式 ---------- */
@media (max-width: 768px) {
  :root {
    --fs-hero: 3.5rem;
    --fs-3xl: 2.75rem;
    --fs-2xl: 2rem;
    --sp-7: 5rem;
    --sp-6: 4rem;
  }
  .container, .container-narrow, .container-wide { width: 92%; }
  body { cursor: auto; }
  button, a { cursor: pointer; }
}

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