/* ===========================================================
   晴空科技官网 · 全站样式
   设计语言：纸、墨、贴纸、手绘线。不用渐变，不用圆角卡片阵列。
   组织顺序：变量 → 基础 → 通用组件 → 页头/首屏 → 区块 → 内页 → 页脚 → 响应式
   =========================================================== */

:root {
  --paper: #fbf6ec;
  --paper-deep: #f3e9d9;
  --paper-card: #fffdf7;
  --ink: #2b2118;
  --ink-2: #4a3c2e;
  --ink-3: #7a6952;
  --line: #dfd0b8;
  --line-soft: #ece1cf;
  --terracotta: #c4573b;
  --terracotta-deep: #a6432a;
  --mustard: #e0a83c;
  --mint: #6fa287;
  --sky: #4e7fa8;

  --hand-radius: 255px 18px 225px 18px / 18px 225px 18px 255px;
  --card-radius: 6px 12px 8px 14px;
  --shadow-paper: 3px 4px 0 rgba(43, 33, 24, 0.12), 0 16px 28px -20px rgba(43, 33, 24, 0.5);
  --shadow-lift: 6px 8px 0 rgba(43, 33, 24, 0.14), 0 22px 34px -22px rgba(43, 33, 24, 0.55);
  --container: 1180px;

  --sans: "PingFang SC", "HarmonyOS Sans SC", "Noto Sans SC", "Microsoft YaHei",
    "Hiragino Sans GB", system-ui, -apple-system, "Segoe UI", sans-serif;
  --kai: "Kaiti SC", "STKaiti", KaiTi, "楷体", "FangSong", serif;
}

[data-theme="coral"] {
  --accent: #c4573b;
  --accent-deep: #a6432a;
  --accent-soft: #fbe9e2;
}

[data-theme="ink"] {
  --accent: #4a4238;
  --accent-deep: #2b2118;
  --accent-soft: #ebe5d9;
}

[data-theme="amber"] {
  --accent: #c98a1e;
  --accent-deep: #a6701a;
  --accent-soft: #fdf0d6;
}

[data-theme="sky"] {
  --accent: #4e7fa8;
  --accent-deep: #3c6489;
  --accent-soft: #e6eef4;
}

/* ---------- 基础 ---------- */

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  position: relative;
  margin: 0;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-2);
  background-color: var(--paper);
}

/* 纸张颗粒：盖在最上层但不可交互 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 6;
  pointer-events: none;
  background-image: url("/img/grain.svg");
  background-size: 180px 180px;
  opacity: 0.16;
  mix-blend-mode: multiply;
}

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

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  color: inherit;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  color: var(--ink);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.012em;
}

h1 {
  font-size: clamp(34px, 4.6vw, 58px);
  line-height: 1.16;
}

h2 {
  font-size: clamp(26px, 3.2vw, 42px);
  line-height: 1.24;
}

h3 {
  font-size: 19px;
  font-weight: 700;
}

p {
  margin: 0;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

::selection {
  background: rgba(224, 168, 60, 0.35);
}

:focus-visible {
  outline: 3px solid var(--terracotta);
  outline-offset: 3px;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 28px;
}

.hero-inner > *,
.sec-head > *,
.detail-grid > *,
.about-grid > *,
.facts > *,
.notes > *,
.works > *,
.channels > *,
.steps > * {
  min-width: 0;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 60;
  padding: 10px 18px;
  border: 2px solid var(--ink);
  border-radius: var(--hand-radius);
  background: var(--paper-card);
  font-size: 14px;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 14px;
}

/* ---------- 通用文字 ---------- */

.sec-num {
  display: inline-block;
  font-family: var(--kai);
  font-size: 16px;
  letter-spacing: 0.2em;
  color: var(--terracotta);
}

.mark {
  display: inline-block;
  font-style: normal;
  padding-bottom: 0.06em;
  background-image: url("/img/underline.svg");
  background-repeat: no-repeat;
  background-position: left bottom;
  background-size: 100% 0.26em;
}

.icon {
  display: inline-flex;
}

.icon svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---------- 胶带 ---------- */

.tape {
  position: absolute;
  display: block;
  width: 78px;
  height: 22px;
  background: rgba(222, 189, 128, 0.62);
  box-shadow: 0 1px 0 rgba(43, 33, 24, 0.08);
  clip-path: polygon(2% 6%, 100% 0, 98% 94%, 0 100%);
  z-index: 3;
}

.tape--tl {
  top: -11px;
  left: 26px;
  transform: rotate(-6deg);
}

.tape--tr {
  top: -11px;
  right: 26px;
  transform: rotate(5deg);
}

.tape--top {
  top: -13px;
  left: 50%;
  transform: translateX(-50%) rotate(-2deg);
}

.tape--mini {
  top: -9px;
  left: 20px;
  width: 54px;
  height: 17px;
  transform: rotate(-7deg);
}

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 26px;
  border: 2px solid var(--ink);
  border-radius: var(--hand-radius);
  background: var(--paper-card);
  color: var(--ink);
  font-size: 15.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
  box-shadow: 3px 3px 0 var(--ink);
  transition: transform 0.16s ease, box-shadow 0.16s ease, background-color 0.16s ease;
}

.btn .icon svg {
  width: 18px;
  height: 18px;
  stroke-width: 2;
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--ink);
}

.btn-primary {
  background: var(--terracotta);
  color: #fff;
}

.btn-primary:hover {
  background: var(--terracotta-deep);
}

.btn-sm {
  padding: 10px 20px;
  font-size: 14px;
}

.link-hand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 3px;
  border-bottom: 2px dashed var(--ink-3);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  transition: color 0.16s ease, border-color 0.16s ease;
}

.link-hand .icon svg {
  width: 18px;
  height: 18px;
  stroke-width: 2;
}

.link-hand:hover {
  color: var(--terracotta);
  border-color: var(--terracotta);
}

/* ---------- 页头 ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(251, 246, 236, 0.94);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px dashed var(--line);
  transition: box-shadow 0.2s ease;
}

.site-header.is-scrolled {
  box-shadow: 0 8px 24px -22px rgba(43, 33, 24, 0.9);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 78px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.brand img {
  width: 42px;
  height: 42px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.brand-text strong {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--ink);
}

.brand-text em {
  font-style: normal;
  font-family: var(--kai);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav a {
  padding: 8px 14px;
  font-size: 15.5px;
  color: var(--ink-2);
  transition: color 0.16s ease;
}

.site-nav a:hover,
.site-nav a.is-active {
  color: var(--terracotta);
}

.site-nav .nav-cta {
  margin-left: 12px;
  padding: 8px 20px;
  border: 2px solid var(--ink);
  border-radius: var(--hand-radius);
  background: var(--mustard);
  color: var(--ink);
  font-size: 15px;
  font-weight: 700;
  box-shadow: 2px 2px 0 var(--ink);
  transition: transform 0.16s ease, box-shadow 0.16s ease;
}

.site-nav .nav-cta:hover {
  color: var(--ink);
  transform: translate(-1px, -1px);
  box-shadow: 4px 4px 0 var(--ink);
}

.nav-toggle {
  display: none;
  width: 46px;
  height: 42px;
  padding: 0;
  border: 2px solid var(--ink);
  border-radius: 10px 14px 10px 14px;
  background: var(--paper-card);
  box-shadow: 2px 2px 0 var(--ink);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 5px auto;
  border-radius: 2px;
  background: var(--ink);
  transition: transform 0.22s ease, opacity 0.22s ease;
}

.nav-toggle[aria-expanded="true"] span:first-child {
  transform: translateY(3.5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:last-child {
  transform: translateY(-3.5px) rotate(-45deg);
}

/* ---------- 首屏 ---------- */

.hero {
  padding: clamp(38px, 5.5vw, 76px) 0 clamp(40px, 5vw, 64px);
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
  align-items: center;
  gap: clamp(28px, 5vw, 64px);
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--kai);
  font-size: 16px;
  letter-spacing: 0.16em;
  color: var(--terracotta);
}

.hero-eyebrow::before {
  content: "";
  width: 30px;
  height: 2px;
  background: var(--terracotta);
}

.hero-copy h1 {
  margin: 20px 0 0;
  letter-spacing: -0.02em;
}

.hero-lead {
  max-width: 32em;
  margin-top: 22px;
  font-size: 16.5px;
  line-height: 1.9;
  color: var(--ink-2);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px 26px;
  margin-top: 32px;
}

.hero-note {
  margin-top: 26px;
  font-family: var(--kai);
  font-size: 14.5px;
  letter-spacing: 0.06em;
  color: var(--ink-3);
}

/* 拼贴：纸片、胶带、便签 */

.collage {
  position: relative;
  min-width: 0;
  height: 476px;
}

.paper {
  position: absolute;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.12);
  box-shadow: var(--shadow-paper);
}

.paper--notice {
  top: 62px;
  left: -6px;
  width: 318px;
  padding: 26px 24px 40px;
  transform: rotate(-3.4deg);
}

.paper-kicker {
  display: block;
  font-family: var(--kai);
  font-size: 13px;
  letter-spacing: 0.26em;
  color: var(--terracotta);
}

.paper-title {
  display: block;
  margin: 8px 0 18px;
  font-size: 27px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.hairline {
  display: block;
  width: 100%;
  height: 1px;
  margin-bottom: 12px;
  background: var(--line-soft);
}

.hairline--short {
  width: 58%;
}

.stamp {
  position: absolute;
  left: 24px;
  bottom: 20px;
  display: grid;
  place-items: center;
  width: 66px;
  height: 66px;
  border: 2px solid var(--terracotta);
  border-radius: 50%;
  color: var(--terracotta);
  font-family: var(--kai);
  font-size: 19px;
  letter-spacing: 0.08em;
  opacity: 0.82;
  transform: rotate(-13deg);
}

.paper--photo {
  top: 0;
  right: 0;
  width: 252px;
  padding: 14px 14px 38px;
  transform: rotate(2.8deg);
}

.photo-frame {
  display: grid;
  place-items: center;
  height: 172px;
  padding: 10px;
  background: #f6f0e2;
}

.photo-frame .crayon {
  width: 100%;
  height: auto;
}

.photo-caption {
  display: block;
  margin-top: 12px;
  text-align: center;
  font-family: var(--kai);
  font-size: 13.5px;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

.sticky {
  position: absolute;
  box-shadow: var(--shadow-paper);
}

.sticky--note {
  left: 84px;
  bottom: 0;
  width: 212px;
  padding: 30px 22px 20px;
  background: #f4ecd0;
  border: 1px solid rgba(43, 33, 24, 0.08);
  transform: rotate(-2.4deg);
}

.sticky--note p {
  font-family: var(--kai);
  font-size: 18px;
  line-height: 1.65;
  color: var(--ink);
}

.hand-check {
  width: 42px;
  margin-top: 10px;
}

.doodle-star {
  position: absolute;
  right: 12px;
  bottom: 34px;
  width: 58px;
  transform: rotate(9deg);
}

/* ---------- 区块骨架 ---------- */

.section {
  padding: clamp(52px, 6.5vw, 92px) 0;
}

.section-tinted {
  background: var(--paper-deep);
  border-top: 1px dashed var(--line);
  border-bottom: 1px dashed var(--line);
}

.sec-head {
  max-width: 820px;
  margin-bottom: clamp(28px, 3.6vw, 46px);
}

.sec-head h2 {
  margin: 10px 0 14px;
}

.sec-lead {
  font-size: 16px;
  line-height: 1.9;
  color: var(--ink-2);
}

/* ---------- 业务卡片 ---------- */

.works {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 22px;
}

.work {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 30px 28px 26px;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.12);
  border-radius: var(--card-radius);
  box-shadow: var(--shadow-paper);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.work::before {
  content: "";
  position: absolute;
  top: -11px;
  left: 30px;
  width: 66px;
  height: 20px;
  background: rgba(222, 189, 128, 0.5);
  clip-path: polygon(2% 6%, 100% 0, 98% 94%, 0 100%);
  transform: rotate(-4deg);
}

.work--0 {
  grid-column: span 7;
  transform: rotate(-0.5deg);
}

.work--1 {
  grid-column: span 5;
  transform: rotate(0.7deg);
}

.work--2 {
  grid-column: span 5;
  transform: rotate(0.4deg);
}

.work--3 {
  grid-column: span 7;
  transform: rotate(-0.4deg);
}

.work:hover {
  box-shadow: var(--shadow-lift);
}

.work--0:hover,
.work--3:hover {
  transform: rotate(-0.5deg) translateY(-5px);
}

.work--1:hover,
.work--2:hover {
  transform: rotate(0.6deg) translateY(-5px);
}

.work-num {
  font-family: var(--kai);
  font-size: 32px;
  line-height: 1;
  color: var(--accent);
}

.work-en {
  margin-top: 14px;
  font-size: 10.5px;
  font-weight: 700;
  letter-spacing: 0.22em;
  color: var(--ink-3);
}

.work h3 {
  margin: 6px 0 8px;
  font-size: clamp(22px, 2.2vw, 27px);
}

.work-tagline {
  font-family: var(--kai);
  font-size: 16.5px;
  color: var(--accent-deep);
}

.work-line {
  margin-top: 10px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-3);
}

.work-more {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  padding-top: 22px;
  font-size: 14px;
  font-weight: 700;
  color: var(--terracotta);
}

.work-more .icon svg {
  width: 17px;
  height: 17px;
  stroke-width: 2;
  transition: transform 0.2s ease;
}

.work:hover .work-more .icon svg {
  transform: translateX(5px);
}

/* ---------- 便签 ---------- */

.notes {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.note {
  position: relative;
  padding: 34px 26px 28px;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.1);
  box-shadow: var(--shadow-paper);
}

.note--0 {
  transform: rotate(-1.1deg);
}

.note--1 {
  transform: rotate(0.8deg);
}

.note--2 {
  transform: rotate(-0.5deg);
}

.note .icon {
  color: var(--terracotta);
}

.note .icon svg {
  width: 26px;
  height: 26px;
}

.note h3 {
  margin: 14px 0 8px;
}

.note p {
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-3);
}

/* ---------- 流程 ---------- */

.steps {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
}

.steps::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 24px;
  height: 12px;
  background: url("/img/wave.svg") repeat-x;
  background-size: 120px 12px;
  opacity: 0.8;
}

.steps li {
  position: relative;
  z-index: 1;
}

.step-dot {
  display: grid;
  place-items: center;
  width: 50px;
  height: 50px;
  border: 2px solid var(--ink);
  border-radius: 50%;
  background: var(--paper-card);
  font-family: var(--kai);
  font-size: 21px;
  color: var(--ink);
  box-shadow: 2px 2px 0 rgba(43, 33, 24, 0.22);
}

.steps h3 {
  margin: 18px 0 8px;
  font-size: 18px;
}

.steps p {
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-3);
}

/* ---------- 较真的地方 ---------- */

.facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 4px 48px;
}

.fact {
  padding: 26px 0 30px;
  border-top: 1px dashed var(--line);
}

.fact-num {
  font-family: var(--kai);
  font-size: 15px;
  letter-spacing: 0.16em;
  color: var(--terracotta);
}

.fact .icon {
  margin: 10px 0 6px;
  color: var(--ink-2);
}

.fact h3 {
  margin-bottom: 8px;
}

.fact p {
  font-size: 14.8px;
  line-height: 1.88;
  color: var(--ink-3);
}

/* ---------- 信纸 CTA ---------- */

.letter {
  position: relative;
  max-width: 880px;
  margin: 0 auto;
  padding: clamp(34px, 4.4vw, 56px) clamp(26px, 4vw, 56px) clamp(34px, 4vw, 48px);
  background: var(--paper-card);
  border: 2px dashed rgba(43, 33, 24, 0.2);
  border-radius: 10px;
  text-align: center;
  box-shadow: var(--shadow-paper);
  transform: rotate(-0.3deg);
}

.letter h2 {
  font-size: clamp(25px, 3vw, 36px);
}

.letter p {
  max-width: 30em;
  margin: 16px auto 28px;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--ink-2);
}

/* ---------- 内页头部 ---------- */

.page-hero {
  padding: clamp(34px, 4.6vw, 60px) 0 clamp(30px, 4vw, 50px);
  border-bottom: 1px dashed var(--line);
}

.page-hero-inner {
  max-width: 900px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 22px;
  font-size: 13px;
  color: var(--ink-3);
}

.breadcrumb a:hover {
  color: var(--terracotta);
}

.page-hero h1 {
  margin: 12px 0 18px;
  font-size: clamp(30px, 4.2vw, 52px);
}

.page-lead {
  max-width: 40em;
  font-size: 16.5px;
  line-height: 1.9;
  color: var(--ink-2);
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 26px;
}

.chips li {
  padding: 6px 15px;
  border: 1.5px dashed rgba(43, 33, 24, 0.28);
  border-radius: 20px;
  background: var(--paper-card);
  font-family: var(--kai);
  font-size: 14px;
  color: var(--ink-2);
}

.detail-en {
  display: block;
  font-family: var(--kai);
  font-size: 15px;
  letter-spacing: 0.24em;
  color: var(--accent, var(--terracotta));
}

.detail-hero {
  background: var(--accent-soft, var(--paper-deep));
}

/* ---------- 活动详情 ---------- */

.detail-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
  gap: clamp(30px, 5vw, 60px);
  align-items: start;
}

.detail-copy h2 {
  margin: 10px 0 22px;
}

.detail-copy p {
  margin-bottom: 16px;
  font-size: 15.5px;
  line-height: 1.95;
  color: var(--ink-2);
}

.detail-copy .detail-summary {
  font-family: var(--kai);
  font-size: 19px;
  line-height: 1.8;
  color: var(--ink);
}

.detail-copy .detail-note {
  margin-top: 8px;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-size: 15px;
  line-height: 1.9;
  color: var(--ink-2);
}

.detail-note strong {
  color: var(--ink);
}

.detail-aside {
  position: sticky;
  top: 98px;
  display: grid;
  gap: 22px;
}

.aside-block {
  padding: 26px 24px;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.12);
  border-radius: var(--card-radius);
  box-shadow: var(--shadow-paper);
}

.aside-block h3 {
  margin-bottom: 14px;
  font-size: 17px;
}

.aside-block--note {
  position: relative;
  background: #f4ecd0;
  border-style: dashed;
  transform: rotate(1deg);
}

.aside-block--note p {
  margin: 0 0 18px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-2);
}

.checklist {
  display: grid;
  gap: 12px;
}

.checklist li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 14.5px;
  color: var(--ink-2);
}

.checklist .icon svg {
  width: 18px;
  height: 18px;
  margin-top: 4px;
  color: var(--terracotta);
  stroke-width: 2.2;
}

/* ---------- 手写清单 ---------- */

.handlist {
  max-width: 900px;
  border-bottom: 1px dashed var(--line);
}

.handlist li {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 24px;
  padding: 24px 0;
  border-top: 1px dashed var(--line);
}

.handlist-num {
  font-family: var(--kai);
  font-size: 22px;
  line-height: 1.5;
  color: var(--terracotta);
}

.handlist h3 {
  margin-bottom: 6px;
  font-size: 19px;
}

.handlist p {
  font-size: 14.8px;
  line-height: 1.88;
  color: var(--ink-3);
}

/* ---------- 下一项 ---------- */

.next-card {
  display: block;
  padding: clamp(28px, 4vw, 46px);
  background: var(--accent-soft, var(--paper-deep));
  border: 1px dashed rgba(43, 33, 24, 0.22);
  border-radius: 10px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.next-label {
  font-family: var(--kai);
  font-size: 14px;
  letter-spacing: 0.2em;
  color: var(--accent-deep, var(--ink-3));
}

.next-card h2 {
  margin: 10px 0 8px;
  font-size: clamp(24px, 3vw, 34px);
}

.next-card p {
  font-family: var(--kai);
  font-size: 17px;
  color: var(--ink-2);
}

.next-more {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 22px;
  font-size: 14.5px;
  font-weight: 700;
  color: var(--accent-deep, var(--terracotta));
}

.next-more .icon svg {
  width: 17px;
  height: 17px;
  stroke-width: 2;
}

/* ---------- 关于 ---------- */

.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
  gap: clamp(30px, 5vw, 60px);
  align-items: start;
}

.about-copy p {
  margin-bottom: 18px;
  font-size: 16.5px;
  line-height: 1.95;
  color: var(--ink-2);
}

.about-copy p:first-child {
  font-family: var(--kai);
  font-size: 20px;
  line-height: 1.85;
  color: var(--ink);
}

.about-note {
  position: relative;
  padding: 30px 28px;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.12);
  border-radius: var(--card-radius);
  box-shadow: var(--shadow-paper);
  transform: rotate(-0.6deg);
}

.about-note h2 {
  margin: 10px 0 14px;
  font-size: clamp(21px, 2.4vw, 26px);
}

.about-note p {
  font-size: 14.8px;
  line-height: 1.9;
  color: var(--ink-2);
}

/* ---------- 合作入口 ---------- */

.channels {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 22px;
  max-width: 900px;
}

.channel {
  position: relative;
  padding: 32px 28px 26px;
  background: var(--paper-card);
  border: 1px solid rgba(43, 33, 24, 0.12);
  border-radius: var(--card-radius);
  box-shadow: var(--shadow-paper);
}

.channel--mail {
  transform: rotate(-0.5deg);
}

.channel--wechat {
  transform: rotate(0.5deg);
}

.channel .icon {
  color: var(--terracotta);
}

.channel-label {
  display: block;
  margin-top: 14px;
  font-family: var(--kai);
  font-size: 14px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
}

.channel-value {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 6px;
  font-size: 23px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink);
}

a.channel-value {
  display: inline-flex;
  padding-bottom: 2px;
  border-bottom: 2px dashed var(--line);
  transition: color 0.16s ease, border-color 0.16s ease;
}

a.channel-value:hover {
  color: var(--terracotta);
  border-color: var(--terracotta);
}

.channel p {
  margin-top: 10px;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--ink-3);
}

.copy-btn {
  padding: 5px 14px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--mustard);
  color: var(--ink);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  box-shadow: 2px 2px 0 var(--ink);
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background-color 0.15s ease;
}

.copy-btn:hover {
  transform: translate(-1px, -1px);
  box-shadow: 3px 3px 0 var(--ink);
}

.copy-btn.is-copied {
  background: var(--mint);
}

/* ---------- 404 ---------- */

.error-hero {
  padding: clamp(52px, 7vw, 96px) 0 clamp(52px, 7vw, 96px);
}

.error-hero .hero-actions {
  margin-top: 28px;
}

/* ---------- 页脚 ---------- */

.site-footer {
  padding-top: clamp(44px, 5.5vw, 64px);
  background: var(--paper-deep);
  border-top: 2px dashed var(--line);
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) repeat(3, minmax(0, 1fr));
  gap: 30px;
  padding-bottom: clamp(32px, 4vw, 48px);
}

.footer-slogan {
  margin-top: 18px;
  font-family: var(--kai);
  font-size: 19px;
  color: var(--ink-2);
}

.footer-note {
  margin-top: 10px;
  font-size: 12.5px;
  color: var(--ink-3);
}

.footer-col h3 {
  margin-bottom: 14px;
  font-family: var(--kai);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--ink-3);
}

.footer-col ul {
  display: grid;
  gap: 9px;
}

.footer-col a {
  font-size: 14.5px;
  color: var(--ink-2);
  transition: color 0.16s ease;
}

.footer-col a:hover {
  color: var(--terracotta);
}

.footer-contact li {
  display: grid;
  gap: 1px;
}

.footer-contact span {
  font-size: 12.5px;
  color: var(--ink-3);
}

.footer-contact a,
.footer-contact strong {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-2);
  word-break: break-all;
}

.footer-contact a:hover {
  color: var(--terracotta);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 20px 28px 26px;
  border-top: 1px dashed var(--line);
  font-size: 12.5px;
  color: var(--ink-3);
}

/* ---------- 背景装饰 ---------- */

.decor {
  position: absolute;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  color: #b8a488;
}

/* 极淡的练习本横线，作为整页底色 */
.decor-grid {
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    to bottom,
    rgba(207, 189, 158, 0.38) 0 1px,
    transparent 1px 46px
  );
  opacity: 0.5;
}

.decor-item {
  position: absolute;
  opacity: 0.42;
}

.decor-sun {
  top: 17%;
  right: 4vw;
  width: 94px;
  transform: rotate(9deg);
}

.decor-plane {
  top: 6%;
  left: 4.5vw;
  width: 84px;
  transform: rotate(-8deg);
}

.decor-pencil {
  top: 30%;
  right: 3vw;
  width: 124px;
  transform: rotate(-14deg);
}

.decor-star {
  top: 43%;
  left: 3vw;
  width: 52px;
  transform: rotate(-12deg);
}

.decor-cloud {
  top: 55%;
  right: 6vw;
  width: 108px;
}

.decor-spiral {
  top: 68%;
  left: 3.5vw;
  width: 82px;
  transform: rotate(-6deg);
}

.decor-blots {
  top: 86%;
  left: 2.5vw;
  width: 108px;
}

.hero-arcs {
  position: absolute;
  right: -22px;
  top: -26px;
  z-index: 0;
  width: 96%;
  max-width: 520px;
  pointer-events: none;
}

.hero .collage {
  position: relative;
  z-index: 1;
}

.hero-inner {
  position: relative;
}

.hero-stamp {
  position: absolute;
  top: -6px;
  right: 6px;
  display: grid;
  place-items: center;
  width: 108px;
  height: 108px;
  border: 3px solid var(--accent, var(--terracotta));
  border-radius: 50%;
  color: var(--accent, var(--terracotta));
  font-family: var(--kai);
  font-size: 30px;
  letter-spacing: 0.1em;
  opacity: 0.16;
  transform: rotate(-12deg);
}

.page-hero-inner {
  position: relative;
}

@media (max-width: 1400px) {
  .decor-item {
    opacity: 0.32;
  }
}

@media (max-width: 1180px) {
  .decor-item {
    opacity: 0.24;
  }

  .decor-star,
  .decor-blots,
  .decor-cloud {
    display: none;
  }
}

@media (max-width: 880px) {
  .decor {
    display: none;
  }

  .hero-arcs {
    display: none;
  }

  .hero-stamp {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .btn,
  .work,
  .next-card {
    transition: none;
  }
}

/* ===========================================================
   响应式
   =========================================================== */

@media (max-width: 1080px) {
  .works {
    gap: 20px;
  }

  .work--0,
  .work--1,
  .work--2,
  .work--3 {
    grid-column: span 6;
  }

  .facts {
    gap: 4px 36px;
  }
}

@media (max-width: 960px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .collage {
    order: 2;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
    height: auto;
    width: 100%;
    max-width: 560px;
    margin: 10px auto 0;
  }

  .collage .paper,
  .collage .sticky {
    position: relative;
    top: auto;
    right: auto;
    bottom: auto;
    left: auto;
    width: auto;
    transform: none;
  }

  .collage .doodle-star {
    display: none;
  }

  .collage .paper--notice {
    padding-bottom: 30px;
  }

  .stamp {
    right: 18px;
    bottom: 14px;
    width: 56px;
    height: 56px;
    font-size: 16px;
  }

  .photo-frame {
    height: 150px;
  }

  .sticky--note {
    grid-column: span 2;
    display: flex;
    align-items: center;
    gap: 18px;
    padding: 24px 22px;
  }

  .sticky--note .tape {
    top: -9px;
  }

  .hand-check {
    margin-top: 0;
  }

  .detail-grid,
  .about-grid,
  .notes,
  .facts {
    grid-template-columns: minmax(0, 1fr);
  }

  .detail-aside {
    position: static;
  }

  .steps {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
  }

  .steps::before {
    display: none;
  }

  .steps li {
    display: grid;
    grid-template-columns: 50px minmax(0, 1fr);
    column-gap: 18px;
  }

  .step-dot {
    grid-row: span 2;
  }

  .steps h3 {
    margin-top: 8px;
  }

  .footer-top {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px;
  }
}

@media (max-width: 880px) {
  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 14px;
    right: 14px;
    display: grid;
    gap: 2px;
    padding: 14px;
    background: var(--paper-card);
    border: 2px solid var(--ink);
    border-radius: 10px 18px 12px 20px;
    box-shadow: 4px 4px 0 rgba(43, 33, 24, 0.9);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
  }

  .site-nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .site-nav a {
    padding: 12px 14px;
    border-radius: 8px;
    font-size: 16px;
  }

  .site-nav a:hover {
    background: var(--paper-deep);
  }

  .site-nav .nav-cta {
    margin: 8px 0 0;
    text-align: center;
  }

  .header-inner {
    position: relative;
    min-height: 70px;
  }
}

@media (max-width: 680px) {
  body {
    font-size: 15.5px;
  }

  .container {
    padding: 0 20px;
  }

  .hero {
    padding-top: 28px;
  }

  .hero-copy h1 br {
    display: none;
  }

  .hero-lead {
    font-size: 15.5px;
  }

  .hero-actions {
    gap: 14px 18px;
    margin-top: 26px;
  }

  .collage {
    grid-template-columns: minmax(0, 1fr);
    max-width: 400px;
  }

  .sticky--note {
    grid-column: auto;
  }

  .collage .paper--photo {
    display: none;
  }

  .paper--notice {
    transform: none;
  }

  .work {
    grid-column: span 12 !important;
    transform: none !important;
  }

  .work:hover {
    transform: translateY(-4px) !important;
  }

  .note--0,
  .note--1,
  .note--2,
  .about-note,
  .aside-block--note,
  .channel,
  .letter {
    transform: none;
  }

  .handlist li {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 14px;
    padding: 20px 0;
  }

  .handlist-num {
    font-size: 18px;
  }

  .letter {
    padding: 30px 22px 28px;
  }

  .footer-top {
    grid-template-columns: minmax(0, 1fr);
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    padding: 18px 20px 24px;
  }
}