:root {
  color-scheme: light;
  font-family: "Helvetica Neue", Arial, sans-serif;
  --text: #111;
  --muted: #555;
  --border: #e5e5e5;
  --link: #000;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: #fff;
  color: var(--text);
}

.page {
  max-width: 880px;
  margin: 0 auto;
  padding: 48px 20px 80px;
}

.header {
  text-align: center;
  margin-bottom: 48px;
}

h1 {
  margin: 0 0 10px;
  font-size: 40px;
  font-weight: 300;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.support {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 28px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  margin-bottom: 36px;
}

.support h2 {
  margin: 0 0 6px;
  font-size: 22px;
  font-weight: 400;
}

.support p {
  margin: 0;
  color: var(--muted);
}

.coffee-btn {
  background: #000;
  color: #fff;
  text-decoration: none;
  padding: 12px 18px;
  letter-spacing: 0.04em;
  font-weight: 600;
  text-transform: uppercase;
  border: 1px solid #000;
}

.coffee-btn:hover {
  background: #fff;
  color: #000;
}

.datasets-header {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
}

.datasets h2 {
  margin: 0;
  font-size: 24px;
  font-weight: 400;
}

.small {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.category-group {
  margin-top: 22px;
}

.category-heading {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #777;
  margin: 16px 0 6px;
}

.category-list {
  border-top: 1px solid var(--border);
}

.dataset-card {
  display: grid;
  grid-template-columns: 1fr 28px auto;
  column-gap: 12px;
  align-items: start;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
}

.dataset-card:last-child {
  border-bottom: none;
}

.dataset-text {
  display: block;
}

.dataset-text h4 {
  margin: 0 0 6px;
  font-size: 18px;
  font-weight: 500;
  letter-spacing: -0.01em;
}

.name-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.dataset-text .meta {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.download-btn {
  background: #000;
  color: #fff;
  text-decoration: none;
  padding: 9px 14px;
  letter-spacing: 0.04em;
  font-weight: 600;
  font-size: 13px;
  text-transform: uppercase;
  border: 1px solid #000;
}

.download-btn:hover {
  background: #fff;
  color: #000;
}

.empty {
  padding: 12px 0;
  color: var(--muted);
}

.helpful {
  margin-top: 40px;
}

.helpful h2 {
  margin: 0 0 12px;
  font-size: 20px;
  font-weight: 500;
}

.helpful-list {
  border-top: 1px solid var(--border);
}

.helpful-item {
  display: block;
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  text-decoration: none;
  color: inherit;
}

.helpful-item:hover .helpful-title {
  text-decoration: underline;
}

.helpful-title {
  font-weight: 600;
  font-size: 16px;
}

.helpful-desc {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.info {
  position: relative;
  grid-column: 2 / 3;
  align-self: start;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 18px;
  height: 18px;
  border: 1px solid #d7d7d7;
  border-radius: 50%;
  font-size: 12px;
  color: #777;
  background: #f7f7f7;
  cursor: default;
  transition: color 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.info:hover {
  color: #000;
  border-color: #c7c7c7;
  background: #fff;
}

.info .tooltip {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  bottom: -4px;
  translate: 0 100%;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
  color: var(--text);
  font-size: 13px;
  line-height: 1.4;
  width: min(280px, 80vw);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.08);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease, transform 0.15s ease;
  z-index: 5;
}

.info:hover .tooltip {
  opacity: 1;
  transform: translate(-50%, 12px);
}

.contact {
  margin-top: 20px;
  color: #666;
  font-size: 14px;
}

.contact a {
  color: inherit;
}

footer {
  margin-top: 48px;
  color: #777;
  font-size: 13px;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

@media (max-width: 640px) {
  .support {
    flex-direction: column;
    align-items: flex-start;
  }

  .dataset-card {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }
}