/* ============================================
   pengi-kun.ai - スタイルシート
   デザイン参考: ollama.com（クリーン&ミニマル）
   ============================================ */

/* --- CSS Variables --- */
:root {
  --color-bg: #ffffff;
  --color-bg-secondary: #f9fafb;
  --color-bg-card: #f4f4f5;
  --color-text: #18181b;
  --color-text-secondary: #71717a;
  --color-text-tertiary: #a1a1aa;
  --color-primary: #18181b;
  --color-primary-text: #ffffff;
  --color-border: #e4e4e7;
  --color-border-light: #f4f4f5;
  --color-code-bg: #f4f4f5;
  --color-code-text: #18181b;
  --color-accent: #2563eb;
  --font-sans: 'Inter', 'Noto Sans JP', system-ui, -apple-system, sans-serif;
  --font-mono: 'SF Mono', 'Menlo', 'Consolas', 'Liberation Mono', monospace;
  --max-width: 1200px;
  --header-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--color-accent);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* --- Container --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* --- Buttons --- */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: var(--color-primary);
  color: var(--color-primary-text);
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: opacity 0.2s;
  text-decoration: none;
}

.btn-primary:hover {
  opacity: 0.85;
  color: var(--color-primary-text);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: 1px solid var(--color-border);
  color: var(--color-text);
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: background-color 0.2s;
  text-decoration: none;
}

.btn-outline:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-text);
}

/* ============================================
   Header
   ============================================ */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
}

.header-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 32px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 18px;
  color: var(--color-text);
  text-decoration: none;
}

.logo:hover {
  color: var(--color-text);
}

.logo img {
  width: 32px;
  height: 32px;
}

.header-nav {
  display: flex;
  gap: 24px;
}

.header-nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
}

.header-nav a:hover {
  color: var(--color-text);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Mobile menu */
.mobile-menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
}

.mobile-menu-btn:hover {
  background-color: var(--color-bg-secondary);
}

.hamburger {
  width: 20px;
  height: 14px;
  position: relative;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text);
  position: absolute;
  left: 0;
  transition: all 0.3s;
}

.hamburger span:nth-child(1) { top: 0; }
.hamburger span:nth-child(2) { top: 6px; }
.hamburger span:nth-child(3) { top: 12px; }

.mobile-menu-btn.active .hamburger span:nth-child(1) {
  top: 6px;
  transform: rotate(45deg);
}

.mobile-menu-btn.active .hamburger span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-btn.active .hamburger span:nth-child(3) {
  top: 6px;
  transform: rotate(-45deg);
}

.mobile-menu {
  display: none;
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: 16px 24px;
  z-index: 99;
}

.mobile-menu.active {
  display: block;
}

.mobile-menu a {
  display: block;
  padding: 12px 0;
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text);
  border-bottom: 1px solid var(--color-border-light);
}

.mobile-menu a:last-child {
  border-bottom: none;
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
  padding: 80px 0 60px;
  text-align: center;
  border-bottom: 1px solid var(--color-border);
}

.hero-icon {
  width: 120px;
  height: 120px;
  margin: 0 auto 32px;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.hero-command {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background-color: var(--color-code-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 12px 16px;
  font-family: var(--font-mono);
  font-size: 14px;
  margin-bottom: 16px;
}

.hero-command code {
  color: var(--color-code-text);
}

.copy-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 4px;
  color: var(--color-text-tertiary);
  transition: all 0.2s;
}

.copy-btn:hover {
  background-color: var(--color-border);
  color: var(--color-text);
}

.copy-btn svg {
  width: 16px;
  height: 16px;
}

.hero-sub {
  font-size: 16px;
  color: var(--color-text-secondary);
}

/* ============================================
   Demo Section
   ============================================ */
.demo {
  padding: 80px 0;
}

.tab-group {
  display: flex;
  gap: 8px;
  margin-bottom: 40px;
}

.tab-item {
  padding: 8px 20px;
  border-radius: 24px;
  border: 1px solid var(--color-border);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: all 0.2s;
}

.tab-item:hover {
  background-color: var(--color-bg-secondary);
  color: var(--color-text);
}

.tab-item.active {
  background-color: var(--color-primary);
  color: var(--color-primary-text);
  border-color: var(--color-primary);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.tab-text h3 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.3;
}

.tab-text p {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.tab-command {
  display: flex;
  align-items: center;
  gap: 12px;
  background-color: var(--color-code-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 12px 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  margin-bottom: 16px;
}

.tab-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
}

.tab-link:hover {
  color: var(--color-accent);
}

/* Terminal Mock */
.terminal-mock {
  background-color: #1e1e1e;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.12);
}

.terminal-dots {
  display: flex;
  gap: 8px;
  padding: 12px 16px;
  background-color: #2d2d2d;
}

.terminal-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.terminal-dot-red { background-color: #ff5f57; }
.terminal-dot-yellow { background-color: #febc2e; }
.terminal-dot-green { background-color: #28c840; }

.terminal-body {
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: #d4d4d4;
  line-height: 1.8;
  min-height: 200px;
}

.terminal-body .prompt {
  color: #28c840;
}

.terminal-body .user-msg {
  color: #569cd6;
}

.terminal-body .ai-msg {
  color: #d4d4d4;
}

.terminal-body .highlight {
  color: #dcdcaa;
}

.terminal-body .dim {
  color: #6a737d;
}

/* Chat Mock */
.chat-mock {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
}

.chat-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px;
  border-bottom: 1px solid var(--color-border);
}

.chat-avatar {
  width: 36px;
  height: 36px;
  background-color: var(--color-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.chat-avatar img {
  width: 24px;
  height: 24px;
  filter: invert(1);
}

.chat-header-text {
  font-size: 14px;
  font-weight: 600;
}

.chat-header-sub {
  font-size: 12px;
  color: var(--color-text-secondary);
}

.chat-messages {
  padding: 16px;
  min-height: 200px;
}

.chat-bubble {
  max-width: 80%;
  padding: 10px 14px;
  border-radius: 12px;
  font-size: 14px;
  line-height: 1.5;
  margin-bottom: 12px;
}

.chat-bubble.user {
  background-color: var(--color-primary);
  color: var(--color-primary-text);
  margin-left: auto;
  border-bottom-right-radius: 4px;
}

.chat-bubble.ai {
  background-color: var(--color-bg-card);
  color: var(--color-text);
  border-bottom-left-radius: 4px;
}

.chat-bubble .mention {
  font-weight: 600;
  color: var(--color-accent);
}

/* ============================================
   Features Section
   ============================================ */
.features {
  padding: 80px 0;
  border-top: 1px solid var(--color-border);
}

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

.section-header h2 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 12px;
}

.section-header p {
  font-size: 16px;
  color: var(--color-text-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  padding: 24px;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  transition: box-shadow 0.2s;
}

.feature-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.feature-icon {
  width: 40px;
  height: 40px;
  margin-bottom: 16px;
  color: var(--color-text);
}

.feature-icon svg {
  width: 100%;
  height: 100%;
}

.feature-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ============================================
   Integrations Section
   ============================================ */
.integrations {
  padding: 80px 0;
  border-top: 1px solid var(--color-border);
}

.integrations-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.integrations-category h3 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.integration-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 8px;
  transition: background-color 0.2s;
}

.integration-item:hover {
  background-color: var(--color-bg-secondary);
}

.integration-icon {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

/* ============================================
   CTA Section
   ============================================ */
.cta {
  padding: 80px 0;
  border-top: 1px solid var(--color-border);
}

.cta-card {
  background-color: var(--color-bg-card);
  border-radius: 16px;
  padding: 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}

.cta-content h2 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 16px;
}

.cta-content ul {
  list-style: disc;
  padding-left: 20px;
}

.cta-content li {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.cta-buttons {
  display: flex;
  flex-direction: column;
  gap: 12px;
  flex-shrink: 0;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-copyright {
  font-size: 13px;
  color: var(--color-text-tertiary);
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  font-size: 13px;
  color: var(--color-text-secondary);
}

.footer-links a:hover {
  color: var(--color-text);
}

/* ============================================
   Utility
   ============================================ */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .integrations-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .hero h1 {
    font-size: 36px;
  }

  .hero {
    padding: 60px 0 40px;
  }

  .tab-content.active {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .tab-text h3 {
    font-size: 24px;
  }

  .cta-card {
    flex-direction: column;
    padding: 32px;
    text-align: center;
  }

  .cta-content ul {
    text-align: left;
  }

  .header-nav {
    display: none;
  }

  .header-right .btn-outline,
  .header-right .btn-primary {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .footer-container {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }

  .footer-links {
    flex-wrap: wrap;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 28px;
  }

  .hero-command {
    font-size: 12px;
    padding: 10px 12px;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .integrations-grid {
    grid-template-columns: 1fr;
  }

  .tab-group {
    flex-wrap: wrap;
  }

  .tab-text h3 {
    font-size: 20px;
  }

  .demo, .features, .integrations, .cta {
    padding: 48px 0;
  }
}