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

:root {
  --color-bg:      #F0F4F8;
  --color-surface: #FFFFFF;
  --color-border:  #E2E8F0;
  --color-text:    #1A202C;
  --color-muted:   #718096;
  --color-accent:  #1F2937;
  --font: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI',
          'Noto Sans JP', sans-serif;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(0,0,0,0.10);
}

body {
  font-family: var(--font);
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

/* ===== Header ===== */
.site-header {
  padding: 24px 24px 0;
}

.logo {
  font-size: 1.5rem;
  font-weight: 500;
  letter-spacing: .02em;
  /* font-weight: 900; */
  /* letter-spacing: -0.04em; */
  color: var(--color-text);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.logo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-accent);
  display: inline-block;
  flex-shrink: 0;
}

/* ===== Main ===== */
main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 48px 24px;
  gap: 48px;
}

.hero {
  text-align: center;
}

.hero-title {
  font-size: clamp(2rem, 8vw, 3rem);
  font-weight: 500;
  letter-spacing: .02em;
  /* letter-spacing: -0.04em; */
  line-height: 1.1;
}

.hero-sub {
  margin-top: 12px;
  font-size: clamp(0.9rem, 3vw, 1.1rem);
  color: var(--color-muted);
}

/* ===== Tools grid ===== */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  width: 100%;
  max-width: 720px;
}

@media (max-width: 520px) {
  .tools-grid {
    grid-template-columns: 1fr;
    max-width: 360px;
  }
}

.tool-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: transform 0.15s, box-shadow 0.15s;
  border: 1.5px solid transparent;
}

.tool-card:hover {
  box-shadow: 0 8px 32px rgba(0,0,0,0.13);
  border-color: var(--color-accent);
}

.tool-card:active {
  transform: translateY(0);
}

.tool-thumb {
  width: 100%;
  border-radius: 8px;
  display: block;
  object-fit: cover;
}

.tool-name {
  font-size: 1.1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.tool-desc {
  font-size: 0.88rem;
  color: var(--color-muted);
  line-height: 1.5;
}

.tool-badge {
  display: inline-block;
  margin-top: 4px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-accent);
  background: #E5E7EB;
  padding: 2px 8px;
  border-radius: 999px;
  align-self: flex-start;
}

/* ===== Footer ===== */
.site-footer {
  padding: 24px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-muted);
}