/* ---------- Fonts ---------- */
/* LXGW 文楷 —— 网站界面用，已按本站文案子集化到 126KB */
@font-face {
  font-family: 'LXGW WenKai';
  src: url('/assets/lxgw-wenkai-subset.woff2') format('woff2');
  font-display: swap;
  font-weight: normal;
  font-style: normal;
}

/* 鸿雷板书简体 —— 信件正文用，子集化后从 11MB 砍到 5MB woff2 */
@font-face {
  font-family: 'HongLei BanShu';
  src: url('/assets/honglei-banshu.woff2') format('woff2');
  font-display: block;
  font-weight: normal;
  font-style: normal;
}

:root {
  --paper: #f3ead4;
  --paper-deep: #e8dcb9;
  --ink: #1a1a1a;
  --ink-soft: #3a342a;
  --accent: #a8322a;
  --accent-soft: #c87470;
  --border: #d6c89a;
  --bg: #ece2c5;
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: 'LXGW WenKai', 'LXGW WenKai Screen', 'PingFang SC', 'Hiragino Sans GB', serif;
  color: var(--ink);
  background-color: var(--bg);
  background-image:
    radial-gradient(circle at 20% 10%, rgba(168, 50, 42, 0.04), transparent 40%),
    radial-gradient(circle at 80% 80%, rgba(168, 50, 42, 0.04), transparent 40%);
  min-height: 100vh;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* HongLei BanShu 字体栈：未安装时优雅降级到楷体 */
.font-banshu {
  font-family: 'HongLei BanShu', '鸿雷板书简体', 'STKaiti', 'KaiTi', '楷体', serif;
}

/* ---------- Layout ---------- */
.container {
  max-width: 640px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

/* ---------- Header ---------- */
.site-header {
  text-align: center;
  margin-bottom: 36px;
  padding-bottom: 20px;
  border-bottom: 1px dashed var(--border);
}

.brand {
  font-family: 'LXGW WenKai Mono', 'SF Mono', Menlo, monospace;
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--accent);
  opacity: 0.7;
  margin: 0 0 12px;
  text-transform: lowercase;
}

.site-title {
  font-size: 32px;
  font-weight: 500;
  letter-spacing: 4px;
  color: var(--ink);
  margin: 0 0 8px;
}

.site-title .accent {
  color: var(--accent);
}

.site-subtitle {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0;
  letter-spacing: 2px;
  opacity: 0.7;
}

/* ---------- Form ---------- */
.form-plain {
  margin: 0;
}

.field {
  margin-bottom: 24px;
}

.field:last-child {
  margin-bottom: 0;
}

.field label {
  display: block;
  font-size: 14px;
  margin-bottom: 8px;
  color: var(--ink-soft);
  letter-spacing: 2px;
}

.field input,
.field textarea {
  width: 100%;
  padding: 12px 14px;
  font-family: inherit;
  font-size: 16px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--border);
  border-radius: 6px;
  outline: none;
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
}

.field input:focus,
.field textarea:focus {
  border-color: var(--accent);
  background: rgba(255, 255, 255, 0.85);
  box-shadow: 0 0 0 3px rgba(168, 50, 42, 0.1);
}

.field textarea {
  resize: vertical;
  min-height: 120px;
  line-height: 1.7;
}

.field .hint {
  display: block;
  font-size: 12px;
  color: var(--ink-soft);
  margin-top: 6px;
  opacity: 0.6;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 12px 28px;
  font-family: inherit;
  font-size: 16px;
  letter-spacing: 4px;
  color: var(--paper);
  background: var(--accent);
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
  text-decoration: none;
  text-align: center;
}

.btn:hover {
  background: #8e2823;
}

.btn:active {
  transform: translateY(1px);
}

.btn:disabled {
  background: #c4b69a;
  cursor: not-allowed;
}

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

.btn-secondary:hover {
  background: rgba(168, 50, 42, 0.08);
}

.btn-large {
  display: block;
  width: 100%;
  padding: 14px;
  font-size: 18px;
  letter-spacing: 8px;
  margin-top: 8px;
}

.btn-row {
  display: flex;
  gap: 12px;
  margin-top: 20px;
}

.btn-row .btn {
  flex: 1;
}

/* ---------- Loading ---------- */
.loading-wrap {
  text-align: center;
  padding: 80px 20px;
}

.loading-title {
  font-size: 22px;
  letter-spacing: 4px;
  color: var(--ink);
  margin-bottom: 12px;
}

.loading-sub {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 32px;
  letter-spacing: 2px;
  opacity: 0.7;
}

.ink-dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin: 0 4px;
  border-radius: 50%;
  background: var(--accent);
  animation: ink-pulse 1.4s infinite ease-in-out both;
}

.ink-dot:nth-child(1) { animation-delay: -0.32s; }
.ink-dot:nth-child(2) { animation-delay: -0.16s; }

@keyframes ink-pulse {
  0%, 80%, 100% { opacity: 0.2; transform: scale(0.8); }
  40% { opacity: 1; transform: scale(1); }
}

/* ---------- Letter View ---------- */
.letter-stage {
  margin: 0 auto;
  max-width: 100%;
  text-align: center;
}

.letter-canvas-wrap {
  position: relative;
  aspect-ratio: 1000 / 1700;
  max-width: min(420px, 100%);
  max-height: calc(100vh - 300px);
  max-height: calc(100dvh - 300px);
  margin: 0 auto;
  cursor: zoom-in;
  box-shadow: 0 4px 24px rgba(60, 40, 10, 0.15);
  transition: transform 0.2s;
}

.letter-canvas-wrap:hover {
  transform: translateY(-2px);
}

.letter-canvas-wrap canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.zoom-hint {
  position: absolute;
  bottom: 8px;
  right: 8px;
  font-size: 11px;
  color: rgba(60, 40, 10, 0.55);
  background: rgba(241, 230, 200, 0.85);
  padding: 3px 8px;
  border-radius: 12px;
  pointer-events: none;
  letter-spacing: 1px;
}

/* ---------- Zoom Modal ---------- */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(20, 15, 10, 0.92);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  overflow: auto;
  -webkit-overflow-scrolling: touch;
}

.modal-content {
  width: max-content;
  max-width: 95vw;
  margin: auto;
}

.modal img {
  display: block;
  width: auto;
  height: auto;
  max-width: 95vw;
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.6);
}

.modal-close {
  position: fixed;
  top: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.3);
  color: #fff;
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.modal-close:hover {
  background: rgba(255, 255, 255, 0.25);
}

/* ---------- How it works ---------- */
.how-it-works {
  margin-top: 40px;
  padding: 20px 22px 18px;
  border-top: 1px dashed var(--border);
}

.how-title {
  font-size: 15px;
  letter-spacing: 4px;
  color: var(--ink-soft);
  margin: 0 0 14px;
  text-align: center;
  opacity: 0.85;
}

.how-list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.how-list li {
  font-size: 14px;
  line-height: 1.9;
  color: var(--ink-soft);
  padding-left: 32px;
  position: relative;
  counter-increment: step;
}

.how-list li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 4px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--paper);
  font-size: 12px;
  text-align: center;
  line-height: 22px;
  font-family: 'LXGW WenKai Mono', monospace;
}

.how-list strong {
  color: var(--ink);
  font-weight: 500;
}

.how-foot {
  margin: 16px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
  text-align: center;
  opacity: 0.7;
  letter-spacing: 1px;
}

.how-foot strong {
  color: var(--accent);
  font-weight: 500;
  font-family: 'LXGW WenKai Mono', 'SF Mono', Menlo, monospace;
  letter-spacing: 2px;
}

/* ---------- Footer ---------- */
.site-footer {
  text-align: center;
  margin-top: 32px;
  font-size: 12px;
  color: var(--ink-soft);
  opacity: 0.5;
  letter-spacing: 1px;
}

/* ---------- Error / Hidden ---------- */
.hidden {
  display: none !important;
}

.error-box {
  margin-top: 16px;
  padding: 12px;
  background: rgba(168, 50, 42, 0.08);
  border: 1px solid rgba(168, 50, 42, 0.3);
  border-radius: 4px;
  color: var(--accent);
  font-size: 14px;
  text-align: center;
}

/* ---------- Responsive ---------- */
@media (max-width: 480px) {
  .container { padding: 20px 16px 40px; }
  .site-title { font-size: 26px; letter-spacing: 2px; }
  .btn-large { letter-spacing: 4px; font-size: 16px; }
}

/* 信件详情页：紧凑头部，把更多空间留给信纸 */
.letter-stage + .btn-row,
.letter-stage .btn-row {
  max-width: 420px;
  margin-left: auto;
  margin-right: auto;
}

body.page-letter .site-header {
  margin-bottom: 16px;
  padding-bottom: 12px;
}

body.page-letter .site-title {
  font-size: 22px;
  margin-bottom: 4px;
}

body.page-letter .site-subtitle {
  font-size: 12px;
}

body.page-letter .container {
  padding-top: 16px;
  padding-bottom: 24px;
}

body.page-letter .site-footer {
  display: none;
}

.domain-tip {
  text-align: center;
  font-size: 13px;
  color: var(--ink-soft);
  opacity: 0.6;
  letter-spacing: 1px;
  margin-top: 24px;
  margin-bottom: 0;
}

.domain-tip strong {
  color: var(--accent);
  font-weight: 500;
  font-family: 'LXGW WenKai Mono', 'SF Mono', Menlo, monospace;
  letter-spacing: 2px;
}