:root {
  color-scheme: light;
  --ink: #171717;
  --muted: #66645f;
  --line: #dedbd2;
  --paper: #f5f3ee;
  --panel: #ffffff;
  --blue: #2563eb;
  --teal: #0f766e;
  --rose: #9f1239;
  --gold: #a16207;
  --shadow: 0 12px 32px rgba(0, 0, 0, 0.05);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans TC", sans-serif;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 24px clamp(18px, 5vw, 64px);
  border-bottom: 1px solid var(--line);
  background: rgba(245, 243, 238, 0.94);
  position: sticky;
  top: 0;
  z-index: 5;
  backdrop-filter: blur(12px);
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--gold);
  font-size: 13px;
  font-weight: 700;
}

h1,
h2,
h3,
p {
  margin: 0;
  letter-spacing: 0;
}

h1 {
  font-size: clamp(28px, 4vw, 48px);
  line-height: 1.05;
}

nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

button,
.open-link {
  min-height: 38px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--ink);
  font: inherit;
  font-weight: 650;
}

button {
  padding: 0 14px;
  cursor: pointer;
}

button.active {
  border-color: var(--ink);
  background: var(--ink);
  color: #fff;
}

main {
  width: min(1120px, 100%);
  margin: 0 auto;
  padding: clamp(22px, 4vw, 48px) clamp(14px, 4vw, 40px) 56px;
}

.summary {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 14px;
}

.summary strong {
  color: var(--ink);
  font-weight: 750;
}

.summary small,
.meta,
.section-title p {
  color: var(--muted);
}

.section-title {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.section-title h2 {
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.06;
}

.briefing-list {
  display: grid;
  gap: 12px;
}

.briefing-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 18px;
  align-items: center;
  min-height: 104px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.tag {
  display: inline-flex;
  margin-bottom: 8px;
  font-size: 12px;
  font-weight: 750;
}

.tag.x {
  color: var(--blue);
}

.tag.skool {
  color: var(--teal);
}

h3 {
  font-size: clamp(18px, 2vw, 24px);
  line-height: 1.24;
}

.meta {
  margin-top: 6px;
  font-size: 14px;
}

.open-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 88px;
  padding: 0 14px;
  border-color: var(--ink);
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  white-space: nowrap;
}

.empty {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--muted);
}

@media (max-width: 720px) {
  .topbar {
    align-items: stretch;
    flex-direction: column;
  }

  nav {
    justify-content: flex-start;
  }

  .summary,
  .briefing-card {
    grid-template-columns: 1fr;
  }

  .section-title {
    align-items: flex-start;
    flex-direction: column;
  }

  .open-link {
    width: 100%;
  }
}