:root {
  --sky-0: #e8f6ff;
  --sky-1: #b9e4fb;
  --sky-2: #2aabee;
  --sky-3: #2481cc;
  --sky-4: #125a96;
  --ink: #0f2438;
  --ink-soft: #4a6478;
  --card: rgba(255, 255, 255, 0.78);
  --stroke: rgba(36, 129, 204, 0.18);
  --ok: #1f9d63;
  --err: #d64545;
  --shadow: 0 24px 60px rgba(18, 90, 150, 0.18);
  --radius: 28px;
  --font-display: 'Outfit', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-body: 'Source Sans 3', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 12% -10%, #ffffff 0%, transparent 55%),
    radial-gradient(900px 500px at 100% 0%, #7fd0f8 0%, transparent 50%),
    linear-gradient(165deg, var(--sky-0) 0%, var(--sky-1) 42%, #8ecff0 100%);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.45'/%3E%3C/svg%3E");
  opacity: 0.045;
  mix-blend-mode: multiply;
  z-index: 0;
}

.sky-birds {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.sky-birds span {
  position: absolute;
  width: 42px;
  height: 18px;
  opacity: 0.16;
  background: no-repeat center / contain
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 64 28'%3E%3Cpath fill='%23125a96' d='M2 18c8-2 14-10 18-16 2 8 8 14 18 16-10 1-16 6-18 12-2-6-8-11-18-12zm34 2c6-1 10-6 13-12 1 6 5 10 13 12-7 1-11 4-13 9-1-5-5-8-13-9z'/%3E%3C/svg%3E");
  animation: drift 22s linear infinite;
}

.sky-birds span:nth-child(1) {
  top: 12%;
  left: -10%;
  animation-duration: 26s;
}
.sky-birds span:nth-child(2) {
  top: 28%;
  left: -20%;
  width: 28px;
  animation-duration: 32s;
  animation-delay: -8s;
}
.sky-birds span:nth-child(3) {
  top: 18%;
  left: -5%;
  width: 34px;
  animation-duration: 28s;
  animation-delay: -14s;
}

@keyframes drift {
  from {
    transform: translateX(0) translateY(0);
  }
  to {
    transform: translateX(120vw) translateY(-18px);
  }
}

.page {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 28px 18px 40px;
}

.card {
  width: min(440px, 100%);
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  padding: 36px 28px 28px;
  text-align: center;
  animation: rise 0.7s cubic-bezier(0.22, 1, 0.36, 1) both;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(18px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.logo {
  width: 88px;
  height: 88px;
  border-radius: 24px;
  object-fit: cover;
  box-shadow: 0 12px 28px rgba(36, 129, 204, 0.28);
  animation: rise 0.8s 0.05s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.brand {
  margin: 18px 0 0;
  font-family: var(--font-display);
  font-size: clamp(28px, 7vw, 34px);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--sky-4);
  animation: rise 0.75s 0.1s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.tagline {
  margin: 8px 0 0;
  color: var(--ink-soft);
  font-size: 15px;
  letter-spacing: 0.08em;
  animation: rise 0.75s 0.16s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.platform-hint {
  margin: 18px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.5;
  min-height: 1.5em;
  animation: rise 0.75s 0.2s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 22px;
  animation: rise 0.75s 0.24s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.btn {
  appearance: none;
  border: 0;
  border-radius: 999px;
  padding: 14px 20px;
  font-family: inherit;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, opacity 0.18s ease;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
}

.btn:active:not(:disabled) {
  transform: scale(0.98);
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.btn--primary {
  color: #fff;
  background: linear-gradient(135deg, var(--sky-2), var(--sky-3));
  box-shadow: 0 10px 24px rgba(42, 171, 238, 0.35);
}

.btn--primary:hover:not(:disabled) {
  box-shadow: 0 14px 30px rgba(42, 171, 238, 0.45);
  transform: translateY(-1px);
}

.btn--ghost {
  color: var(--sky-3);
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(36, 129, 204, 0.28);
}

.btn--ghost:hover:not(:disabled) {
  background: #fff;
}

.btn--text {
  background: transparent;
  color: var(--ink-soft);
  font-weight: 500;
  font-size: 14px;
  min-height: 40px;
  padding: 8px;
}

.meta {
  margin-top: 18px;
  animation: rise 0.75s 0.28s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.version {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(36, 129, 204, 0.1);
  color: var(--sky-4);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.changelog {
  margin-top: 14px;
  text-align: left;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--stroke);
  overflow: hidden;
}

.changelog summary {
  cursor: pointer;
  list-style: none;
  padding: 12px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--sky-4);
  user-select: none;
}

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

.changelog summary::after {
  content: '展开';
  float: right;
  font-weight: 500;
  color: var(--ink-soft);
}

.changelog[open] summary::after {
  content: '收起';
}

.changelog-body {
  margin: 0;
  padding: 0 14px 14px;
  white-space: pre-wrap;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
}

.status {
  margin-top: 16px;
  font-size: 12px;
  color: var(--ink-soft);
  min-height: 1.2em;
}

.status--loading {
  color: var(--sky-3);
}

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

.status--error {
  color: var(--err);
}

.foot {
  margin-top: 22px;
  font-size: 12px;
  color: rgba(15, 36, 56, 0.45);
  animation: rise 0.75s 0.32s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.wechat-mask {
  position: fixed;
  inset: 0;
  z-index: 20;
  background: rgba(8, 24, 40, 0.72);
  color: #fff;
  display: flex;
  align-items: flex-start;
  justify-content: flex-end;
  padding: 18px 20px;
}

.wechat-mask[hidden] {
  display: none !important;
}

.wechat-tip {
  max-width: 260px;
  text-align: right;
  font-size: 15px;
  line-height: 1.6;
}

.wechat-tip strong {
  display: block;
  font-size: 17px;
  margin-bottom: 6px;
}

.wechat-arrow {
  font-size: 36px;
  line-height: 1;
  margin-bottom: 8px;
  animation: nudge 1.2s ease-in-out infinite;
}

@keyframes nudge {
  0%,
  100% {
    transform: translate(0, 0);
  }
  50% {
    transform: translate(6px, -6px);
  }
}

@media (min-width: 720px) {
  .page {
    padding: 48px 24px;
  }

  .card {
    padding: 44px 40px 36px;
  }
}