@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=JetBrains+Mono:wght@400&display=swap');

:root {
  --color-canvas: #f7f7f4;
  --color-canvas-soft: #fafaf7;
  --color-surface-card: #ffffff;
  --color-surface-strong: #e6e5e0;
  --color-primary: #f54e00;
  --color-primary-active: #d04200;
  --color-ink: #26251e;
  --color-body: #5a5852;
  --color-body-strong: #26251e;
  --color-muted: #807d72;
  --color-muted-soft: #a09c92;
  --color-on-primary: #ffffff;
  --color-hairline: #e6e5e0;
  --color-hairline-soft: #efeee8;
  --color-hairline-strong: #cfcdc4;
  --color-semantic-success: #1f8a65;
  --color-semantic-error: #cf2d56;

  --rounded-xs: 4px;
  --rounded-sm: 6px;
  --rounded-md: 8px;
  --rounded-lg: 12px;
  --rounded-xl: 16px;
  --rounded-pill: 9999px;

  --spacing-xxs: 4px;
  --spacing-xs: 8px;
  --spacing-sm: 12px;
  --spacing-base: 16px;
  --spacing-md: 20px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 48px;
  --spacing-section: 80px;

  --font-family-base: 'Inter', system-ui, 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --font-family-mono: 'JetBrains Mono', monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.5;
  color: var(--color-body);
  background-color: var(--color-canvas);
}

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

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-xl);
}

.site-nav {
  background-color: var(--color-canvas);
  border-bottom: 1px solid var(--color-hairline);
  height: 64px;
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-brand {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-ink);
  letter-spacing: -0.01em;
}

.nav-brand span {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-body);
  transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-ink);
}

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: var(--spacing-xs);
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.hero-band {
  padding: var(--spacing-section) 0;
  background-color: var(--color-canvas);
}

.hero-band h1 {
  font-size: 72px;
  font-weight: 400;
  line-height: 1.1;
  letter-spacing: -2.16px;
  color: var(--color-ink);
  max-width: 780px;
  margin-bottom: var(--spacing-xl);
}

.hero-band p.hero-sub {
  font-size: 16px;
  font-weight: 400;
  line-height: 1.5;
  color: var(--color-body);
  max-width: 560px;
  margin-bottom: var(--spacing-xxl);
}

.hero-image-wrap {
  margin-top: var(--spacing-xxl);
  border-radius: var(--rounded-lg);
  overflow: hidden;
  border: 1px solid var(--color-hairline);
}

.hero-image-wrap img {
  width: 100%;
  height: 480px;
  object-fit: cover;
}

.badge-pill {
  display: inline-flex;
  align-items: center;
  background-color: var(--color-surface-strong);
  color: var(--color-ink);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.88px;
  text-transform: uppercase;
  border-radius: var(--rounded-pill);
  padding: 4px 10px;
  margin-bottom: var(--spacing-md);
}

.section {
  padding: var(--spacing-section) 0;
}

.section-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.88px;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: var(--spacing-base);
}

.section-title {
  font-size: 36px;
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: -0.72px;
  color: var(--color-ink);
  margin-bottom: var(--spacing-lg);
}

.section-body {
  font-size: 16px;
  line-height: 1.5;
  color: var(--color-body);
  max-width: 680px;
}

.divider {
  height: 1px;
  background-color: var(--color-hairline);
  border: none;
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
}

.article-card {
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  border-radius: var(--rounded-lg);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.article-card:hover {
  border-color: var(--color-hairline-strong);
}

.article-card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.article-card-body {
  padding: var(--spacing-lg);
}

.article-card-cat {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.88px;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: var(--spacing-xs);
}

.article-card-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-ink);
  line-height: 1.4;
  margin-bottom: var(--spacing-sm);
}

.article-card-excerpt {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-body);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
}

.feature-card {
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  border-radius: var(--rounded-lg);
  padding: var(--spacing-lg);
}

.feature-card-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-ink);
  line-height: 1.4;
  margin-bottom: var(--spacing-sm);
}

.feature-card-body {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-body);
}

.article-header {
  padding: var(--spacing-section) 0 var(--spacing-xxl);
  border-bottom: 1px solid var(--color-hairline);
  margin-bottom: var(--spacing-section);
}

.article-header h1 {
  font-size: 52px;
  font-weight: 400;
  letter-spacing: -1.5px;
  line-height: 1.15;
  color: var(--color-ink);
  max-width: 800px;
  margin-bottom: var(--spacing-xl);
}

.article-meta {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  font-size: 13px;
  color: var(--color-muted);
}

.article-meta span {
  display: flex;
  align-items: center;
  gap: var(--spacing-xxs);
}

.article-featured-img {
  width: 100%;
  height: 520px;
  object-fit: cover;
  border-radius: var(--rounded-lg);
  border: 1px solid var(--color-hairline);
  margin: var(--spacing-xxl) 0;
}

.article-body {
  max-width: 780px;
  margin: 0 auto;
}

.article-body h2 {
  font-size: 26px;
  font-weight: 400;
  letter-spacing: -0.325px;
  color: var(--color-ink);
  margin: var(--spacing-xxl) 0 var(--spacing-base);
}

.article-body h3 {
  font-size: 22px;
  font-weight: 400;
  letter-spacing: -0.11px;
  color: var(--color-ink);
  margin: var(--spacing-xl) 0 var(--spacing-sm);
}

.article-body p {
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-body);
  margin-bottom: var(--spacing-base);
}

.article-body ul,
.article-body ol {
  margin: var(--spacing-base) 0 var(--spacing-base) var(--spacing-xl);
}

.article-body li {
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-body);
  margin-bottom: var(--spacing-xs);
}

.info-box {
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline);
  border-left: 3px solid var(--color-ink);
  border-radius: var(--rounded-md);
  padding: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.info-box-title {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.88px;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: var(--spacing-sm);
}

.info-box p {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-body);
  margin-bottom: 0;
}

.related-articles {
  border-top: 1px solid var(--color-hairline);
  padding-top: var(--spacing-section);
  margin-top: var(--spacing-section);
}

.contact-section {
  padding: var(--spacing-section) 0;
  background-color: var(--color-canvas-soft);
  border-top: 1px solid var(--color-hairline);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-section);
}

.form-group {
  margin-bottom: var(--spacing-base);
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-ink);
  margin-bottom: var(--spacing-xs);
}

.form-control {
  width: 100%;
  background-color: var(--color-surface-card);
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--rounded-md);
  padding: 12px 16px;
  height: 44px;
  font-size: 16px;
  font-family: var(--font-family-base);
  color: var(--color-ink);
  outline: none;
  transition: border-color 0.2s ease;
}

.form-control:focus {
  border-color: var(--color-ink);
}

.form-control::placeholder {
  color: var(--color-muted-soft);
}

textarea.form-control {
  height: auto;
  resize: vertical;
  min-height: 120px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-primary);
  color: var(--color-on-primary);
  font-size: 14px;
  font-weight: 500;
  font-family: var(--font-family-base);
  border: none;
  border-radius: var(--rounded-md);
  padding: 10px 18px;
  height: 40px;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.btn-primary:hover {
  background-color: var(--color-primary-active);
  color: var(--color-on-primary);
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.form-message {
  display: none;
  padding: var(--spacing-sm) var(--spacing-base);
  border-radius: var(--rounded-md);
  font-size: 14px;
  margin-top: var(--spacing-sm);
}

.form-message.success {
  background-color: #e6f4ef;
  color: var(--color-semantic-success);
  display: block;
}

.form-message.error {
  background-color: #fce8ed;
  color: var(--color-semantic-error);
  display: block;
}

.site-footer {
  background-color: var(--color-canvas);
  border-top: 1px solid var(--color-hairline);
  padding: 64px 0 48px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xxl);
}

.footer-brand-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-ink);
  margin-bottom: var(--spacing-sm);
}

.footer-brand-name span {
  color: var(--color-primary);
}

.footer-brand-desc {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-body);
  max-width: 240px;
}

.footer-col-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-ink);
  margin-bottom: var(--spacing-base);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.footer-links a {
  font-size: 14px;
  color: var(--color-body);
  transition: color 0.2s ease;
}

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

.footer-bottom {
  border-top: 1px solid var(--color-hairline);
  padding-top: var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-bottom p {
  font-size: 13px;
  color: var(--color-muted);
}

.footer-bottom-links {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
}

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

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

.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: var(--color-surface-card);
  border-top: 1px solid var(--color-hairline);
  padding: var(--spacing-base) var(--spacing-xl);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-xl);
}

.cookie-text {
  font-size: 13px;
  line-height: 1.5;
  color: var(--color-body);
}

.cookie-text a {
  color: var(--color-ink);
  text-decoration: underline;
  text-decoration-color: var(--color-hairline-strong);
}

.cookie-actions {
  display: flex;
  gap: var(--spacing-sm);
  flex-shrink: 0;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-surface-card);
  color: var(--color-ink);
  font-size: 14px;
  font-weight: 500;
  font-family: var(--font-family-base);
  border: 1px solid var(--color-hairline-strong);
  border-radius: var(--rounded-md);
  padding: 10px 18px;
  height: 40px;
  cursor: pointer;
  transition: border-color 0.2s ease;
}

.btn-secondary:hover {
  border-color: var(--color-ink);
}

.page-header {
  padding: var(--spacing-section) 0 var(--spacing-xxl);
  border-bottom: 1px solid var(--color-hairline);
  margin-bottom: var(--spacing-section);
}

.page-header h1 {
  font-size: 52px;
  font-weight: 400;
  letter-spacing: -1.5px;
  color: var(--color-ink);
  margin-bottom: var(--spacing-base);
}

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

.page-body {
  max-width: 780px;
}

.page-body h2 {
  font-size: 26px;
  font-weight: 400;
  letter-spacing: -0.325px;
  color: var(--color-ink);
  margin: var(--spacing-xxl) 0 var(--spacing-base);
}

.page-body h3 {
  font-size: 22px;
  font-weight: 400;
  color: var(--color-ink);
  margin: var(--spacing-xl) 0 var(--spacing-sm);
}

.page-body p {
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-body);
  margin-bottom: var(--spacing-base);
}

.page-body ul, .page-body ol {
  margin: var(--spacing-base) 0 var(--spacing-base) var(--spacing-xl);
}

.page-body li {
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-body);
  margin-bottom: var(--spacing-xs);
}

.page-body .updated-date {
  font-size: 13px;
  color: var(--color-muted);
  margin-bottom: var(--spacing-xl);
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: 13px;
  color: var(--color-muted);
  margin-bottom: var(--spacing-xxl);
}

.breadcrumb a {
  color: var(--color-muted);
}

.breadcrumb a:hover {
  color: var(--color-ink);
}

.breadcrumb-sep {
  color: var(--color-muted-soft);
}

@media (max-width: 1024px) {
  .hero-band h1 {
    font-size: 56px;
  }
  .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--spacing-base);
  }
  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background-color: var(--color-canvas);
    border-bottom: 1px solid var(--color-hairline);
    flex-direction: column;
    padding: var(--spacing-base);
    gap: var(--spacing-base);
  }
  .nav-links.open {
    display: flex;
  }
  .nav-hamburger {
    display: flex;
  }
  .site-nav .container {
    position: relative;
  }
  .hero-band h1 {
    font-size: 36px;
    letter-spacing: -1px;
  }
  .hero-image-wrap img {
    height: 280px;
  }
  .section-title {
    font-size: 28px;
  }
  .article-grid {
    grid-template-columns: 1fr;
  }
  .feature-grid {
    grid-template-columns: 1fr;
  }
  .contact-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-xxl);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    gap: var(--spacing-base);
    align-items: flex-start;
  }
  .article-header h1 {
    font-size: 36px;
    letter-spacing: -0.8px;
  }
  .article-featured-img {
    height: 280px;
  }
  .page-header h1 {
    font-size: 36px;
  }
  .cookie-banner {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-base);
  }
}

@media (max-width: 640px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}