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

/* Base */
:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-secondary: #64748b;
  --color-text: #1e293b;
  --color-text-light: #475569;
  --color-bg: #ffffff;
  --color-bg-light: #f8fafc;
  --color-border: #e2e8f0;
  --max-width: 720px;
  --spacing: 1.5rem;
}

html {
  font-size: 16px;
  line-height: 1.8;
}

body {
  font-family: "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Yu Gothic", "Meiryo", sans-serif;
  color: var(--color-text);
  background-color: var(--color-bg);
}

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--spacing);
}

/* Header */
.site-header {
  text-align: center;
  padding: 3rem 0;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 2rem;
}

.site-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-text);
}

/* Content */
.content {
  padding-bottom: 3rem;
}

.content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-top: 3rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-primary);
}

.content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.content h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.content p {
  margin-bottom: 1rem;
}

.content ul, .content ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.content li {
  margin-bottom: 0.5rem;
}

.content blockquote {
  margin: 1.5rem 0;
  padding: 1rem 1.5rem;
  background-color: var(--color-bg-light);
  border-left: 4px solid var(--color-primary);
  color: var(--color-text-light);
}

.content blockquote p {
  margin-bottom: 0.5rem;
}

.content blockquote p:last-child {
  margin-bottom: 0;
}

.content a {
  color: var(--color-primary);
  text-decoration: none;
}

.content a:hover {
  text-decoration: underline;
}

.content strong {
  font-weight: 700;
}

/* CTA */
.cta {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin: 2rem 0;
  padding: 1.5rem;
  background-color: var(--color-bg-light);
  border-radius: 8px;
  border: 1px solid var(--color-border);
}

.cta-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  background-color: #059669;
  color: #ffffff !important;
  text-decoration: none !important;
  border-radius: 6px;
  font-weight: 700;
  font-size: 1rem;
  transition: background-color 0.2s, transform 0.1s;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.cta-button:hover {
  background-color: #047857;
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.cta-button-secondary {
  background-color: #dc2626;
}

.cta-button-secondary:hover {
  background-color: #b91c1c;
}

/* Button */
.button {
  display: inline-block;
  padding: 0.75rem 1.25rem;
  background-color: #059669;
  color: #ffffff !important;
  text-decoration: none !important;
  border-radius: 4px;
  font-size: 0.875rem;
  font-weight: 600;
  margin-right: 0.5rem;
  margin-bottom: 0.5rem;
  transition: background-color 0.2s, transform 0.1s;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.button:hover {
  background-color: #047857;
  text-decoration: none;
  transform: translateY(-1px);
}

.button-techbookfest {
  background-color: #059669;
}

.button-techbookfest:hover {
  background-color: #047857;
}

.button-stores {
  background-color: #dc2626;
}

.button-stores:hover {
  background-color: #b91c1c;
}

/* Video */
.video-container {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  margin: 1.5rem 0;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

/* Twitter embed */
.twitter-embed {
  margin: 1.5rem 0;
}

/* Figure */
.figure {
  margin: 1.5rem 0;
}

.figure img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
}

.figure figcaption {
  margin-top: 0.5rem;
  font-size: 0.875rem;
  color: var(--color-text-light);
  text-align: center;
}

/* Footer */
.site-footer {
  text-align: center;
  padding: 2rem 0;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-light);
  font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 640px) {
  html {
    font-size: 15px;
  }

  .site-header {
    padding: 2rem 0;
  }

  .site-title {
    font-size: 1.5rem;
  }

  .content h2 {
    font-size: 1.35rem;
  }

  .content h3 {
    font-size: 1.15rem;
  }

  .cta {
    flex-direction: column;
  }

  .cta-button {
    text-align: center;
  }
}