/* 潮汐引力工作室 站点样式
   设计读法：面向中文安卓用户的 AI 陪伴产品官网，明亮编辑风（OpenAI 那种克制、留白、大字），
   原生 CSS + 滚动驱动动效 + 自带字体栈。
   设计旋钮：VARIANCE 7 / MOTION 6 / DENSITY 4
   规则：整套页面只用浅色主题；UI 强调色唯一（品牌蓝 #0A84FF）；
   圆角分三档并全站统一（卡片 20 / 控件 12 / 标签 8）。 */

:root {
  --ink: #0b0b0f;
  --ink-strong: #000000;
  --ink-soft: #3c3c43;
  --muted: #6e6e73;
  --muted-soft: #8e8e93;
  --line: #e6e6ec;
  --line-soft: #f0f0f4;
  --bg: #ffffff;
  --bg-soft: #f6f6f8;
  --bg-elevated: #ffffff;
  --accent: #0a84ff;
  --accent-strong: #0066dd;
  --accent-soft: #eaf3ff;
  --ok: #14915a;
  --warn: #b26a00;
  --danger: #c8372f;
  --radius-card: 20px;
  --radius-control: 12px;
  --radius-chip: 8px;
  --shadow-soft: 0 18px 60px rgba(11, 11, 15, 0.08);
  --shadow-phone: 0 40px 90px rgba(11, 11, 15, 0.18);
  --maxw: 1180px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "HarmonyOS Sans SC", "Noto Sans SC", "Microsoft YaHei", "Helvetica Neue",
    Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #fff;
  padding: 10px 16px;
  border-radius: var(--radius-control);
  z-index: 100;
}

.skip-link:focus {
  left: 16px;
  top: 16px;
}

/* ---------- 顶部导航 ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid transparent;
  transition: border-color 240ms var(--ease), background 240ms var(--ease);
}

.nav.is-scrolled {
  border-bottom-color: var(--line);
  background: rgba(255, 255, 255, 0.88);
}

.nav-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: 66px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  letter-spacing: 0;
}

.brand img {
  width: 30px;
  height: 30px;
  border-radius: 9px;
}

.brand span {
  font-size: 16px;
}

.brand small {
  display: block;
  font-size: 11px;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

.nav-links a {
  padding: 8px 12px;
  border-radius: var(--radius-control);
  font-size: 14.5px;
  color: var(--ink-soft);
  transition: background 180ms var(--ease), color 180ms var(--ease);
}

.nav-links a:hover {
  background: var(--bg-soft);
  color: var(--ink);
}

.nav-links a[aria-current="page"] {
  color: var(--ink);
  font-weight: 600;
  background: var(--bg-soft);
}

.nav-cta {
  margin-left: 10px;
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  background: var(--bg);
  border-radius: var(--radius-control);
  align-items: center;
  justify-content: center;
}

.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  display: block;
  width: 16px;
  height: 1.6px;
  background: var(--ink);
  position: relative;
  content: "";
}

.nav-toggle span::before {
  position: absolute;
  top: -5px;
}

.nav-toggle span::after {
  position: absolute;
  top: 5px;
}

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 48px;
  padding: 0 22px;
  border-radius: var(--radius-control);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  white-space: nowrap;
  cursor: pointer;
  transition: transform 160ms var(--ease), background 180ms var(--ease),
    border-color 180ms var(--ease), color 180ms var(--ease), box-shadow 180ms var(--ease);
}

.btn:active {
  transform: translateY(1px) scale(0.99);
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 10px 26px rgba(10, 132, 255, 0.28);
}

.btn-primary:hover {
  background: var(--accent-strong);
}

.btn-ghost {
  background: var(--bg);
  border-color: var(--line);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: #d5d5dd;
  background: var(--bg-soft);
}

.btn-small {
  height: 38px;
  padding: 0 16px;
  font-size: 14px;
}

.btn[disabled] {
  opacity: 0.55;
  cursor: progress;
}

.text-link {
  color: var(--accent);
  font-weight: 600;
  border-bottom: 1px solid rgba(10, 132, 255, 0.28);
  padding-bottom: 1px;
}

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

/* ---------- 版式 ---------- */

.eyebrow {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.04em;
}

.display {
  font-size: clamp(38px, 5.4vw, 68px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  font-weight: 700;
  margin: 0;
}

.h2 {
  font-size: clamp(28px, 3.4vw, 44px);
  line-height: 1.14;
  letter-spacing: -0.015em;
  font-weight: 700;
  margin: 0;
}

.h3 {
  font-size: 20px;
  line-height: 1.3;
  letter-spacing: -0.01em;
  font-weight: 650;
  margin: 0 0 8px;
}

.lede {
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.65;
  color: var(--muted);
  max-width: 62ch;
  margin: 20px 0 0;
}

.body-copy {
  color: var(--muted);
  margin: 12px 0 0;
  max-width: 68ch;
}

.section {
  padding: clamp(72px, 9vw, 132px) 0;
}

.section-tight {
  padding: clamp(48px, 6vw, 80px) 0;
}

.section-alt {
  background: var(--bg-soft);
}

.section-head {
  max-width: 760px;
  margin-bottom: clamp(32px, 4vw, 56px);
}

.divider {
  height: 1px;
  background: var(--line);
  border: 0;
  margin: 0;
}

/* ---------- 首页 Hero ---------- */

.hero {
  padding: clamp(48px, 7vw, 92px) 0 clamp(56px, 7vw, 104px);
  overflow: clip;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  align-items: center;
  gap: clamp(36px, 5vw, 76px);
}

.hero-copy {
  max-width: 620px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 24px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 11px;
  border: 1px solid var(--line);
  border-radius: var(--radius-chip);
  font-size: 12.5px;
  color: var(--muted);
  background: var(--bg);
}

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

.hero-art {
  position: relative;
  display: flex;
  justify-content: center;
  isolation: isolate;
}

.hero-art::before {
  content: "";
  position: absolute;
  inset: 8% 4% 12%;
  border-radius: 40px;
  background: radial-gradient(120% 90% at 70% 10%, #dceaff 0%, #f4f8ff 45%, #ffffff 100%);
  z-index: -1;
}

.phone {
  width: min(300px, 74vw);
  border-radius: 34px;
  background: #0b0b0f;
  padding: 9px;
  box-shadow: var(--shadow-phone);
  transform: translate3d(0, 0, 0);
  will-change: transform;
}

.phone img {
  width: 100%;
  border-radius: 26px;
  background: #fff;
}

.phone-sm {
  width: min(240px, 62vw);
}

.hero-art .phone-back {
  position: absolute;
  right: 2%;
  bottom: -6%;
  width: min(184px, 46vw);
  opacity: 0.96;
  box-shadow: 0 26px 70px rgba(11, 11, 15, 0.22);
  transform: rotate(4deg);
}

/* ---------- 角色横幅 ---------- */

.role-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
}

.role {
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background: var(--bg);
  padding: 14px;
  transition: transform 220ms var(--ease), box-shadow 220ms var(--ease),
    border-color 220ms var(--ease);
}

.role:hover {
  transform: translateY(-3px);
  border-color: #d8d8e0;
  box-shadow: var(--shadow-soft);
}

.role img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 14px;
}

.role b {
  display: block;
  margin-top: 12px;
  font-size: 15px;
}

.role span {
  display: block;
  font-size: 12.5px;
  color: var(--muted);
  margin-top: 2px;
}

.role-note {
  margin-top: 18px;
  font-size: 13px;
  color: var(--muted-soft);
}

/* ---------- 能力矩阵 ---------- */

.bento {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 14px;
}

.cell {
  grid-column: span 2;
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background: var(--bg);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 168px;
  transition: transform 220ms var(--ease), border-color 220ms var(--ease);
}

.cell:hover {
  transform: translateY(-2px);
  border-color: #d8d8e0;
}

.cell-wide {
  grid-column: span 4;
}

.cell-half {
  grid-column: span 3;
}

.cell-tone {
  background: linear-gradient(150deg, #eef5ff 0%, #ffffff 72%);
  border-color: #dbe8ff;
}

.cell b {
  font-size: 17px;
  font-weight: 650;
}

.cell p {
  margin: 0;
  color: var(--muted);
  font-size: 14.5px;
}

.cell .cell-tag {
  margin-top: auto;
  font-size: 12.5px;
  color: var(--accent);
  font-weight: 600;
}

.cell-visual {
  display: flex;
  gap: 10px;
  align-items: flex-end;
  margin-top: auto;
}

.cell-visual img {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  object-fit: cover;
}

/* ---------- 截图 ---------- */

.shots {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 18px;
  align-items: start;
}

.shot {
  border-radius: var(--radius-card);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

.shot img {
  width: 100%;
}

.shot figcaption {
  padding: 12px 14px;
  font-size: 13px;
  color: var(--muted);
  background: var(--bg);
  border-top: 1px solid var(--line-soft);
}

/* ---------- 下载 ---------- */

.download-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(24px, 4vw, 56px);
  align-items: start;
}

.panel {
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background: var(--bg);
  padding: clamp(20px, 3vw, 30px);
}

.panel-soft {
  background: var(--bg-soft);
}

.spec {
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr);
  gap: 10px 16px;
  font-size: 14.5px;
  margin: 0;
}

.spec dt {
  color: var(--muted);
}

.spec dd {
  margin: 0;
  word-break: break-all;
}

.spec code {
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--ink-soft);
}

.steps {
  margin: 14px 0 0;
  padding-left: 20px;
  color: var(--muted);
  font-size: 14.5px;
}

.steps li {
  margin-bottom: 8px;
}

.status-line {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13.5px;
  color: var(--muted);
  margin-top: 16px;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--muted-soft);
  flex: none;
}

.dot.is-ok {
  background: var(--ok);
}

.dot.is-warn {
  background: var(--warn);
}

/* ---------- 工作室 ---------- */

.studio-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: clamp(28px, 5vw, 64px);
  align-items: start;
}

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

.fact {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-control);
  background: var(--bg);
  font-size: 14.5px;
}

.fact span {
  color: var(--muted);
}

.fact b {
  text-align: right;
}

.timeline {
  margin: 0;
  padding: 0;
  list-style: none;
  border-left: 1px solid var(--line);
}

.timeline li {
  position: relative;
  padding: 0 0 22px 22px;
}

.timeline li::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--accent);
}

.timeline b {
  display: block;
  font-size: 15px;
}

.timeline span {
  color: var(--muted);
  font-size: 14px;
}

/* ---------- 反馈 ---------- */

.form {
  display: grid;
  gap: 16px;
}

.field {
  display: grid;
  gap: 8px;
}

.field label {
  font-size: 14px;
  font-weight: 600;
}

.field small {
  color: var(--muted-soft);
  font-size: 12.5px;
}

input[type="text"],
input[type="email"],
select,
textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-control);
  background: var(--bg);
  color: var(--ink);
  font-size: 15px;
  transition: border-color 180ms var(--ease), box-shadow 180ms var(--ease);
}

textarea {
  min-height: 140px;
  resize: vertical;
}

input::placeholder,
textarea::placeholder {
  color: #9a9aa0;
}

input:focus,
select:focus,
textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(10, 132, 255, 0.16);
  outline: none;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-status {
  font-size: 14px;
  min-height: 22px;
}

.form-status.is-ok {
  color: var(--ok);
}

.form-status.is-error {
  color: var(--danger);
}

/* ---------- FAQ ---------- */

.faq {
  display: grid;
  gap: 10px;
}

.faq details {
  border: 1px solid var(--line);
  border-radius: var(--radius-control);
  background: var(--bg);
  padding: 16px 18px;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::after {
  content: "+";
  float: right;
  color: var(--muted);
  font-weight: 500;
}

.faq details[open] summary::after {
  content: "-";
}

.faq p {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 14.5px;
}

/* ---------- 页脚 ---------- */

.footer {
  border-top: 1px solid var(--line);
  background: var(--bg-soft);
  padding: 56px 0 40px;
  font-size: 14px;
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr));
  gap: 28px;
}

.footer h4 {
  font-size: 13px;
  color: var(--muted);
  font-weight: 600;
  margin: 0 0 12px;
}

.footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

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

.footer-bottom {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  color: var(--muted-soft);
  font-size: 13px;
}

/* ---------- 滚动出现动效 ---------- */

/* 只有在脚本可用时才隐藏待入场元素，避免脚本失败后页面空白 */
html.js-ready .reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
}

html.js-ready .reveal.is-in {
  opacity: 1;
  transform: none;
}

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

  .reveal,
  .role,
  .cell,
  .btn,
  .phone {
    transition: none !important;
    transform: none !important;
    opacity: 1 !important;
  }
}

/* ---------- 响应式 ---------- */

@media (max-width: 980px) {
  .hero-grid,
  .download-grid,
  .studio-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero-art {
    order: -1;
  }

  .hero-art .phone-back {
    right: 12%;
  }

  .cell,
  .cell-wide,
  .cell-half {
    grid-column: span 3;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 720px) {
  .wrap {
    padding: 0 18px;
  }

  .hero {
    padding: 28px 0 56px;
  }

  .hero-grid {
    gap: 30px;
  }

  .phone {
    width: min(250px, 62vw);
  }

  .hero-art .phone-back {
    right: 4%;
    width: min(132px, 33vw);
  }

  .hero-art::before {
    inset: 10% 0 14%;
    border-radius: 28px;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    left: 12px;
    right: 12px;
    top: 62px;
    flex-direction: column;
    align-items: stretch;
    padding: 10px;
    gap: 4px;
    background: var(--bg);
    border: 1px solid var(--line);
    border-radius: var(--radius-card);
    box-shadow: var(--shadow-soft);
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    padding: 11px 12px;
  }

  .nav-cta {
    margin-left: 0;
  }

  .nav-cta .btn {
    width: 100%;
  }

  .cell,
  .cell-wide,
  .cell-half {
    grid-column: span 6;
  }

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

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

  .spec dt {
    margin-top: 6px;
  }

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

  .btn {
    width: 100%;
  }

  .hero-actions .btn {
    flex: 1 1 100%;
  }
}