/* ================================================================
   Prosponsive Download Page — Dark Theme
   ================================================================ */

:root {
  --bg: #f4f6f4;
  --surface: #e6eae7;
  --text-primary: #1f2321;
  --text-secondary: #5c635f;
  --accent: #2f4f3e;
  --accent-hover: #3a6149;
  --border: #d6dbd7;
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

/* ---- Reset ---- */

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

/* ---- Base ---- */

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-stack);
  background-color: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 4rem 1.5rem 2rem;
  max-width: 800px;
  margin: 0 auto;
  width: 100%;
}

/* ---- Hero ---- */

.hero {
  text-align: center;
  padding: 2rem 0 3rem;
}

.app-icon {
  display: block;
  margin: 0 auto 1.5rem;
  border-radius: 22%;
}

h1 {
  font-size: 3rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.tagline {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 2.5rem;
}

/* ---- Download Button ---- */

.download-area {
  margin-bottom: 1.5rem;
}

.btn-download {
  display: inline-block;
  padding: 0.875rem 2.5rem;
  font-size: 1.125rem;
  font-weight: 600;
  color: #f4f6f4;
  background-color: var(--accent);
  border: none;
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.15s ease, transform 0.1s ease;
  min-width: 44px;
  min-height: 44px;
}

.btn-download:hover,
.btn-download:focus-visible {
  background-color: var(--accent-hover);
  transform: translateY(-1px);
}

.btn-download:focus-visible {
  outline: 2px solid var(--accent-hover);
  outline-offset: 3px;
}

.btn-download:active {
  transform: translateY(0);
}

.btn-download[aria-disabled="true"] {
  background-color: var(--border);
  color: var(--text-secondary);
  cursor: default;
  pointer-events: none;
}

/* ---- Version Info ---- */

.version-info {
  margin-top: 0.75rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* ---- Platform Note ---- */

.platform-note {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.platform-switch {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.link-btn {
  background: none;
  border: none;
  color: var(--accent);
  cursor: pointer;
  font-size: inherit;
  font-family: inherit;
  text-decoration: underline;
  padding: 0;
  min-width: 44px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.link-btn:hover,
.link-btn:focus-visible {
  color: var(--accent-hover);
}

.link-btn:focus-visible {
  outline: 2px solid var(--accent-hover);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ---- Requirements ---- */

.requirements {
  width: 100%;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem;
  margin-top: 1rem;
}

.requirements h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.requirements ul {
  list-style: none;
  padding: 0;
}

.requirements li {
  padding: 0.375rem 0;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
}

.requirements li:last-child {
  border-bottom: none;
}

.requirements li strong {
  color: var(--text-primary);
}

.requirements li em {
  color: var(--accent);
  font-style: normal;
}

/* ---- Footer ---- */

footer {
  text-align: center;
  padding: 2rem 1.5rem;
  border-top: 1px solid var(--border);
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

footer p {
  margin-bottom: 0.75rem;
}

footer nav {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
}

footer a {
  color: var(--accent);
  text-decoration: none;
}

footer a:hover,
footer a:focus-visible {
  color: var(--accent-hover);
  text-decoration: underline;
}

footer a:focus-visible {
  outline: 2px solid var(--accent-hover);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ---- Responsive ---- */

@media (max-width: 767px) {
  main {
    padding: 2rem 1rem 1.5rem;
  }

  h1 {
    font-size: 2.25rem;
  }

  .tagline {
    font-size: 1.0625rem;
  }

  .btn-download {
    display: block;
    width: 100%;
    text-align: center;
  }

  .requirements {
    padding: 1.5rem;
  }

  footer nav {
    flex-direction: column;
    gap: 0.75rem;
  }
}

/* ---- Reduced Motion ---- */

@media (prefers-reduced-motion: reduce) {
  .btn-download {
    transition: none;
  }

  .btn-download:hover,
  .btn-download:focus-visible {
    transform: none;
  }
}