*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
:root {
  --bg0: #1d2021;
  --bg1: #282828;
  --fg: #ebdbb2;
  --fg4: #a89984;
  --gray: #7c6f64;
  --border: #3c3836;
  --blue: #83a598;
  --green: #b8bb26;
  --yellow: #fabd2f;
  --card-hover: #32302f;
}
[data-theme="light"] {
  --bg0: #fbf1c7;
  --bg1: #f9f5d7;
  --fg: #3c3836;
  --fg4: #7c6f64;
  --gray: #928374;
  --border: #d5c4a1;
  --blue: #458588;
  --green: #98971a;
  --yellow: #d79921;
  --card-hover: #f2e5c4;
}
body {
  background: var(--bg0);
  color: var(--fg);
  font-family:
    system-ui,
    -apple-system,
    sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition:
    background 0.2s ease,
    color 0.2s ease;
}

.theme-toggle {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--fg);
  font-size: 0.8rem;
  font-weight: 600;
  font-family: inherit;
  padding: 0.4rem 0.75rem;
  border-radius: 0.3rem;
  cursor: pointer;
  letter-spacing: 0.04em;
  transition:
    border-color 0.15s ease,
    color 0.15s ease;
}
.theme-toggle:hover {
  border-color: var(--green);
  color: var(--green);
}

nav {
  padding: 1.4rem 2.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border);
}
.logo {
  font-size: 1.2rem;
  letter-spacing: -0.01em;
  text-decoration: none;
  color: var(--fg);
}

.eyebrow {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 1rem;
}
h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 1.2rem;
}
h1 em {
  font-style: italic;
  color: var(--yellow);
}
.page-heading {
  font-size: 1.4rem;
  line-height: 1.3;
  letter-spacing: -0.01em;
  margin-bottom: 0.75rem;
}
.tagline,
.subtitle {
  font-size: 0.95rem;
  color: var(--fg4);
  line-height: 1.7;
  margin-bottom: 2.2rem;
  max-width: 40ch;
}
.subtitle {
  margin-bottom: 2rem;
}

footer {
  border-top: 1px solid var(--border);
  padding: 1.2rem 2.5rem;
  text-align: center;
  font-size: 0.72rem;
  color: var(--gray);
}

.home-main {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 5rem;
  max-width: 960px;
  margin: 0 auto;
  padding: 5rem 2.5rem;
  width: 100%;
  align-items: start;
}
.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--green);
  color: var(--bg0);
  text-decoration: none;
  padding: 0.8rem 1.5rem;
  border-radius: 0.35rem;
  font-size: 0.85rem;
  font-weight: 600;
  transition: opacity 0.15s ease;
}
.btn-download:hover {
  opacity: 0.85;
}
.sub {
  font-size: 0.75rem;
  color: var(--fg4);
  margin-top: 0.7rem;
}
.features {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}
.feature {
  background: var(--bg1);
  border: 1px solid var(--border);
  border-radius: 0.35rem;
  padding: 1.25rem;
  transition: background 0.15s ease;
}
.feature:hover {
  background: var(--card-hover);
}
.feature strong {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
}
.feature span {
  font-size: 0.82rem;
  color: var(--fg4);
  line-height: 1.55;
}
.qr-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.8rem;
  padding-top: 0.5rem;
}
.qr-block img {
  display: block;
  border: 1px solid var(--border);
  border-radius: 0.4rem;
  background: var(--bg1);
  padding: 0.6rem;
}
.qr-label {
  font-size: 0.7rem;
  color: var(--gray);
  letter-spacing: 0.06em;
  text-align: center;
}

.add-main {
  flex: 1;
  max-width: 520px;
  margin: 0 auto;
  padding: 4rem 2.5rem;
  width: 100%;
}
.sources-label {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gray);
  margin-bottom: 0.5rem;
}
.sources {
  border: 1px solid var(--border);
  border-radius: 0.35rem;
  background: var(--bg1);
  margin-bottom: 2rem;
  overflow: hidden;
}
.source-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--fg);
  word-break: break-all;
  line-height: 1.4;
}
.source-item:last-child {
  border-bottom: none;
}
.source-num {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--fg4);
  min-width: 1.2rem;
  flex-shrink: 0;
}
.btn {
  display: block;
  width: 100%;
  padding: 0.8rem 1.2rem;
  border-radius: 0.35rem;
  font-size: 0.88rem;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  margin-bottom: 0.6rem;
  cursor: pointer;
  border: none;
}
.btn-primary {
  background: var(--green);
  color: var(--bg0);
}
.btn-secondary {
  background: transparent;
  color: var(--fg);
  border: 1px solid var(--border);
}
.hint {
  font-size: 0.73rem;
  color: var(--gray);
  text-align: center;
  margin-top: 0.5rem;
  line-height: 1.6;
}

@media (max-width: 640px) {
  nav {
    padding: 1.2rem 1.5rem;
  }
  .home-main {
    grid-template-columns: 1fr;
    gap: 3rem;
    padding: 3rem 1.5rem;
  }
  .add-main {
    padding: 2.5rem 1.5rem;
  }
  .qr-block {
    align-items: center;
    order: 1;
  }
}