/* Ivyea Translate 门户 —— 叶绿色系，呼应桌面端 App 主题 */
:root {
  --accent: #6BA53F;
  --accent-deep: #4D802F;
  --ink: #2E3A28;
  --ink-2: #5C6B54;
  --ink-3: #93A388;
  --card: rgba(255, 255, 255, 0.72);
  --card-line: rgba(255, 255, 255, 0.9);
  --radius: 20px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

html { background: #FBFDF7; }

body {
  font-family: "PingFang SC", "Microsoft YaHei UI", "Noto Sans CJK SC", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(1200px 700px at 80% -10%, rgba(107, 165, 63, 0.10), transparent 60%),
    linear-gradient(160deg, #F3F8EC 0%, #FBFDF7 45%, #E9F2DF 100%);
  background-attachment: fixed, fixed;
  min-height: 100vh;
  overflow-x: hidden;
}

/* 藤蔓画布铺满整页、垫底 */
#ivy-canvas {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
}

header.nav, main, footer { position: relative; z-index: 1; }

/* ---------- 导航 ---------- */
header.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px clamp(20px, 5vw, 64px);
}
.brand {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--ink);
  font-weight: 700; font-size: 17px; letter-spacing: 0.2px;
}
header.nav nav { display: flex; gap: clamp(14px, 3vw, 30px); align-items: center; }
header.nav nav a {
  color: var(--ink-2); text-decoration: none; font-size: 14.5px;
  transition: color 0.2s;
}
header.nav nav a:hover { color: var(--accent-deep); }
header.nav nav a.gh {
  border: 1px solid rgba(107, 165, 63, 0.4);
  padding: 6px 14px; border-radius: 999px;
}

/* ---------- Hero ---------- */
.hero {
  min-height: calc(100vh - 78px);
  min-height: calc(100svh - 78px);  /* 移动端地址栏收放不跳动 */
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  text-align: center;
  padding: 0 20px 60px;
  position: relative;
}
.hero h1 {
  font-family: "Noto Serif SC", "Songti SC", "SimSun", serif;
  font-size: clamp(44px, 8vw, 88px);
  font-weight: 700;
  line-height: 1.18;
  letter-spacing: 2px;
  animation: rise-in 0.9s cubic-bezier(0.22, 0.9, 0.3, 1) both;
}
.hero .sub { animation: rise-in 0.9s 0.15s cubic-bezier(0.22, 0.9, 0.3, 1) both; }
.hero .cta { animation: rise-in 0.9s 0.3s cubic-bezier(0.22, 0.9, 0.3, 1) both; }
.hero .hint { animation: rise-in 0.9s 0.5s cubic-bezier(0.22, 0.9, 0.3, 1) both, breathe 3s 1.4s ease-in-out infinite; }
@keyframes rise-in {
  from { opacity: 0; transform: translateY(26px); }
  to { opacity: 1; transform: translateY(0); }
}
@media (prefers-reduced-motion: reduce) {
  .hero h1, .hero .sub, .hero .cta, .hero .hint { animation: none; }
}
.hero h1 em {
  font-style: normal;
  color: var(--accent-deep);
  background: linear-gradient(120deg, #7FB250, #4D802F);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero .sub {
  margin-top: 22px;
  font-size: clamp(15px, 2.2vw, 19px);
  line-height: 1.9;
  color: var(--ink-2);
}
.cta { margin-top: 38px; display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.btn {
  display: inline-block;
  padding: 14px 30px;
  border-radius: 999px;
  font-size: 15.5px;
  text-decoration: none;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
}
.btn.primary {
  background: linear-gradient(135deg, #7CB44E, #5B9334);
  color: #fff; font-weight: 600;
  box-shadow: 0 8px 24px rgba(91, 147, 52, 0.35);
}
.btn.primary:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(91, 147, 52, 0.45); }
.btn.ghost {
  background: var(--card);
  border: 1px solid rgba(107, 165, 63, 0.45);
  color: var(--accent-deep);
}
.btn.ghost:hover { transform: translateY(-2px); background: #fff; }

.hint {
  margin-top: 46px;
  font-size: 13px;
  color: var(--ink-3);
  background: var(--card);
  border: 1px solid var(--card-line);
  padding: 8px 18px;
  border-radius: 999px;
  backdrop-filter: blur(6px);
  animation: breathe 3s ease-in-out infinite;
  transition: opacity 0.8s;
}
.hint.gone { opacity: 0; }
@keyframes breathe { 50% { opacity: 0.55; } }

.scroll-cue {
  position: absolute; bottom: 26px; left: 50%;
  transform: translateX(-50%);
  color: var(--ink-3); text-decoration: none; font-size: 20px;
  animation: bob 2s ease-in-out infinite;
}
@keyframes bob { 50% { transform: translate(-50%, 8px); } }

/* ---------- 截图展示 ---------- */
.showcase { padding: 40px 20px 90px; display: flex; justify-content: center; }
.shot-wrap { position: relative; max-width: 860px; width: 100%; }
.shot {
  border-radius: var(--radius);
  border: 1px solid var(--card-line);
  box-shadow: 0 24px 60px rgba(60, 90, 40, 0.18);
  max-width: 100%;
}
.shot.main { width: 100%; display: block; }
.shot.popup {
  position: absolute;
  width: 46%;
  right: -4%;
  bottom: -9%;
  box-shadow: 0 18px 44px rgba(60, 90, 40, 0.28);
}

/* ---------- 功能 ---------- */
section h2 {
  font-family: "Noto Serif SC", "Songti SC", serif;
  text-align: center;
  font-size: clamp(28px, 4.4vw, 42px);
  margin-bottom: 46px;
  letter-spacing: 1px;
}
.features { padding: 60px clamp(20px, 5vw, 64px) 30px; max-width: 1150px; margin: 0 auto; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 22px; }
.card {
  background: var(--card);
  border: 1px solid var(--card-line);
  border-radius: var(--radius);
  padding: 30px 26px;
  backdrop-filter: blur(8px);
  transition: transform 0.2s, box-shadow 0.25s;
}
.card:hover { transform: translateY(-5px); box-shadow: 0 18px 40px rgba(60, 90, 40, 0.14); }
.card .ico { font-size: 30px; }
.card h3 { margin: 14px 0 10px; font-size: 19px; }
.card p { color: var(--ink-2); font-size: 14.5px; line-height: 1.85; }
.card p b { color: var(--accent-deep); }

.grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 14px;
}
.cell {
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.75);
  border-radius: 14px;
  padding: 16px 20px;
  display: flex; flex-direction: column; gap: 5px;
}
.cell b { font-size: 15px; color: var(--ink); }
.cell span { font-size: 13.5px; color: var(--ink-2); line-height: 1.7; }

/* ---------- 常春藤隐喻 ---------- */
.lifecycle { padding: 90px 20px 70px; text-align: center; }
.lifecycle .lead {
  color: var(--ink-2); line-height: 2.05; font-size: 15.5px;
  max-width: 720px; margin: -18px auto 44px;
}
.stages {
  display: flex; justify-content: center; align-items: stretch;
  gap: 10px; flex-wrap: wrap;
}
.stage {
  background: var(--card);
  border: 1px solid var(--card-line);
  border-radius: 16px;
  padding: 18px 26px;
  min-width: 128px;
  backdrop-filter: blur(6px);
}
.stage i {
  display: block; font-style: normal; font-weight: 700;
  color: var(--accent-deep);
  font-family: "Noto Serif SC", serif; font-size: 19px;
}
.stage span { display: block; margin-top: 6px; font-size: 12.5px; color: var(--ink-3); }
.arrow { align-self: center; color: var(--ink-3); }

/* ---------- 下载 ---------- */
.download { padding: 60px 20px 110px; text-align: center; }
.dl-cards {
  display: flex; gap: 22px; justify-content: center; flex-wrap: wrap;
}
.dl-card {
  background: var(--card);
  border: 1px solid var(--card-line);
  border-radius: var(--radius);
  padding: 34px 40px;
  width: min(360px, 92vw);
  backdrop-filter: blur(8px);
}
.dl-card h3 { font-size: 20px; }
.dl-card p { color: var(--ink-2); font-size: 13.5px; margin: 10px 0 22px; line-height: 1.7; }
.req { margin-top: 30px; color: var(--ink-3); font-size: 13px; }
.req a { color: var(--accent-deep); }

/* ---------- 页脚 ---------- */
footer {
  border-top: 1px solid rgba(107, 165, 63, 0.18);
  background: rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(8px);
}
.foot-inner {
  max-width: 1150px; margin: 0 auto;
  padding: 26px clamp(20px, 5vw, 64px);
  display: flex; justify-content: space-between; align-items: center; gap: 18px;
  flex-wrap: wrap;
}
.foot-brand { display: flex; align-items: center; gap: 8px; font-weight: 600; font-size: 14.5px; }
footer nav { display: flex; gap: 22px; }
footer a { color: var(--ink-2); text-decoration: none; font-size: 13.5px; }
footer a:hover { color: var(--accent-deep); }
.copy { color: var(--ink-3); font-size: 12.5px; }

/* ---------- 移动端 ---------- */
@media (max-width: 720px) {
  header.nav { padding: 14px 18px; }
  .brand span { font-size: 15px; }
  .brand img { width: 28px; height: 28px; }
  header.nav nav { gap: 14px; }
  header.nav nav a { font-size: 13px; }
  header.nav nav a.gh { padding: 5px 12px; }

  .hero { padding: 0 22px 48px; }
  .hero h1 { letter-spacing: 0; font-size: clamp(38px, 11vw, 54px); }
  .hero .sub { font-size: 14.5px; line-height: 1.85; margin-top: 16px; }
  .cta { margin-top: 30px; flex-direction: column; width: 100%; max-width: 320px; }
  .cta .btn { width: 100%; text-align: center; padding: 15px 0; }
  .hint { margin-top: 34px; font-size: 12px; padding: 7px 14px; }
  .scroll-cue { display: none; }

  .showcase { padding: 20px 16px 56px; }
  .shot.popup { position: static; width: 78%; margin: 14px auto 0; display: block; }

  section h2 { margin-bottom: 30px; }
  .features { padding: 40px 18px 20px; }
  .card { padding: 24px 20px; }
  .grid { grid-template-columns: 1fr; }

  .lifecycle { padding: 60px 18px 46px; }
  .lifecycle .lead { font-size: 14px; line-height: 1.95; }
  .lifecycle .lead br { display: none; }
  .stages { gap: 8px; }
  .stage { min-width: 0; flex: 1 1 40%; padding: 14px 10px; }
  .arrow { display: none; }

  .download { padding: 40px 18px 80px; }
  .dl-card { padding: 26px 22px; }
  .dl-card .btn { display: block; text-align: center; word-break: break-all; }
  .req { font-size: 12px; padding: 0 10px; }

  .foot-inner { flex-direction: column; text-align: center; padding: 22px 18px; }
}

@media (max-width: 420px) {
  header.nav nav a:not(.gh) { display: none; }  /* 极窄屏只留 GitHub 按钮 */
  .stage { flex: 1 1 44%; }
}