/* achang.vip 个人站：与 pianduoduo.tech 同一套视觉（灰阶纸面、细线分区、单一强调色、一句一行） */

:root {
  --paper: #f5f5f7;
  --raised: #ffffff;
  --sunk: #ebebef;
  --ink: #1d1d1f;
  --ink-2: #55555a;
  --ink-3: #a1a1a6;
  --line: rgba(0, 0, 0, 0.08);
  --line-strong: rgba(0, 0, 0, 0.16);
  --accent: #0071e3;
  --d-canvas: #121212;
  --d-ink: #f2f2f3;
  --d-ink-2: #a0a0a6;
  --d-ink-3: #6c6c74;
  --d-line: rgba(255, 255, 255, 0.08);
  --d-accent: #2f6bff;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Noto Sans SC",
    "Noto Sans CJK SC", "Segoe UI", sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Consolas, "Noto Sans Mono", "DejaVu Sans Mono",
    "PingFang SC", "Microsoft YaHei", monospace;
  --ease: cubic-bezier(0.2, 0, 0, 1);
  --gutter: clamp(20px, 4vw, 56px);
  --wrap: 1200px;
  --section-pad: clamp(72px, 9vw, 128px);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

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

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

h1,
h2,
h3,
p {
  margin: 0;
  text-wrap: pretty;
}

strong {
  font-weight: 600;
  color: var(--ink);
}

.wrap {
  width: 100%;
  max-width: calc(var(--wrap) + var(--gutter) * 2);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.eyebrow {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-2);
}

.eyebrow b {
  font-weight: 500;
  color: var(--ink);
}

.prose {
  display: flex;
  flex-direction: column;
  gap: 0.35em;
}

.prose.lines {
  gap: 0.1em;
}

.lede {
  font-size: 18px;
  color: var(--ink-2);
}

.small {
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-2);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  height: 48px;
  padding: 0 22px;
  border-radius: 4px;
  border: 1px solid transparent;
  font: 500 15px/1 var(--sans);
  cursor: pointer;
  transition: background-color 200ms var(--ease), border-color 200ms var(--ease);
}

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

.btn-primary:hover {
  background: #000;
}

.btn-primary .arrow {
  color: #5ea8ff;
}

.btn-quiet {
  border-color: var(--line-strong);
  color: var(--ink);
}

.btn-quiet:hover {
  border-color: var(--ink);
}

/* 页头 */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(245, 245, 247, 0.92);
  backdrop-filter: saturate(1.4) blur(12px);
  -webkit-backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid var(--line);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

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

.brand b {
  font-size: 19px;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.brand span {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-2);
}

.site-nav {
  display: flex;
  gap: 32px;
  font-size: 15px;
}

.site-nav a {
  color: var(--ink-2);
  transition: color 200ms var(--ease);
}

.site-nav a:hover {
  color: var(--ink);
}

/* 首屏 */

.hero {
  padding: clamp(64px, 9vw, 128px) 0 clamp(72px, 9vw, 120px);
}

.hero .wrap {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: clamp(40px, 6vw, 96px);
  align-items: end;
}

.hero-copy {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.hero h1 {
  font-weight: 400;
  font-size: clamp(2.25rem, 4.6vw, 3.75rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.index {
  border-top: 1px solid var(--ink);
}

.index-title {
  padding: 14px 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-2);
  border-bottom: 1px solid var(--line);
}

.index a {
  display: grid;
  grid-template-columns: 36px minmax(0, 1fr) auto;
  gap: 12px;
  align-items: baseline;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  transition: color 200ms var(--ease);
}

.index a:hover {
  color: var(--accent);
}

.index .no {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-3);
}

.index .name {
  font-size: 18px;
  font-weight: 600;
}

.index .name small {
  display: block;
  font-size: 14px;
  font-weight: 400;
  color: var(--ink-2);
}

.status {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  color: var(--ink-2);
  white-space: nowrap;
}

.status.live {
  border-color: rgba(0, 113, 227, 0.4);
  color: var(--accent);
}

/* 通用区块 */

.section {
  padding: var(--section-pad) 0;
  border-top: 1px solid var(--line);
}

.section.white {
  background: var(--raised);
}

.section-head {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: clamp(40px, 5vw, 64px);
}

.section-head h2 {
  font-weight: 400;
  font-size: clamp(1.875rem, 3.4vw, 2.75rem);
  line-height: 1.35;
}

/* 项目 */

.projects {
  display: flex;
  flex-direction: column;
  gap: clamp(64px, 8vw, 104px);
}

.project {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: center;
}

.project.flip {
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
}

.project.flip .project-copy {
  order: 2;
}

.project-copy {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.project-copy h3 {
  font-weight: 400;
  font-size: clamp(1.625rem, 2.8vw, 2.25rem);
  line-height: 1.3;
}

.project-copy .prose {
  color: var(--ink-2);
}

.project-copy .btn {
  align-self: flex-start;
  margin-top: 8px;
}

.project-shot {
  margin: 0;
}

.project-shot img {
  width: 100%;
  border-radius: 12px;
  box-shadow: 0 0 0 1px var(--line), 0 24px 64px rgba(0, 0, 0, 0.08);
}

.project-shot figcaption {
  margin-top: 12px;
}

/* 内容平台 */

.channels {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid var(--ink);
}

.channel {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 28px 28px 8px 0;
}

.channel + .channel {
  padding-left: 28px;
  border-left: 1px solid var(--line);
}

.channel .platform {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-2);
}

.channel .account {
  font-size: 22px;
  font-weight: 600;
  line-height: 1.4;
}

.channel p {
  font-size: 15px;
  color: var(--ink-2);
}

.channels-sub {
  margin: clamp(40px, 5vw, 56px) 0 16px;
}

.channel-link {
  align-self: flex-start;
  margin-top: 4px;
  font-size: 15px;
  color: var(--accent);
  border-bottom: 1px solid rgba(0, 113, 227, 0.3);
  transition: border-color 200ms var(--ease);
}

.channel-link:hover {
  border-bottom-color: var(--accent);
}

/* 联系 */

.contact {
  background: var(--d-canvas);
  color: var(--d-ink);
  padding: var(--section-pad) 0;
}

.contact .wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: clamp(40px, 6vw, 88px);
  align-items: center;
}

.contact .eyebrow {
  color: var(--d-ink-2);
}

.contact .eyebrow b {
  color: var(--d-ink);
}

.contact h2 {
  font-weight: 400;
  font-size: clamp(2rem, 4vw, 3.25rem);
  line-height: 1.3;
  margin: 16px 0 24px;
}

.contact .prose {
  color: var(--d-ink-2);
}

.contact strong {
  color: var(--d-ink);
}

.contact-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.qr {
  width: 180px;
  height: 180px;
  padding: 12px;
  border-radius: 10px;
  background: #fff;
}

.wechat-id {
  font-family: var(--mono);
  font-size: 18px;
  color: var(--d-ink);
  user-select: all;
}

.contact-card .small {
  color: var(--d-ink-3);
}

/* 页脚 */

.site-footer {
  background: var(--sunk);
  padding: 32px 0;
  font-size: 14px;
  color: var(--ink-2);
}

.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px 32px;
}

.site-footer a:hover {
  color: var(--ink);
}

@media (max-width: 960px) {
  .site-nav {
    gap: 20px;
  }

  .hero .wrap,
  .project,
  .project.flip,
  .contact .wrap {
    grid-template-columns: minmax(0, 1fr);
  }

  .project.flip .project-copy {
    order: 0;
  }

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

  .channel + .channel {
    padding-left: 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .contact-card {
    align-items: flex-start;
  }
}

@media (max-width: 600px) {
  body {
    font-size: 16px;
  }

  .brand span {
    display: none;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0ms !important;
  }
}