/* ===========================
   GateCHA Landing Page Styles
   =========================== */

/* --- Custom Properties --- */
:root {
  --color-primary: #0D9488;
  --color-primary-dark: #0F766E;
  --color-primary-light: #CCFBF1;
  --color-neutral-900: #0F172A;
  --color-neutral-700: #334155;
  --color-neutral-400: #94A3B8;
  --color-neutral-200: #E2E8F0;
  --color-neutral-100: #F1F5F9;
  --color-neutral-50: #F8FAFC;
  --color-white: #FFFFFF;
  --color-code-bg: #1E293B;
  --color-code-text: #E2E8F0;
  --color-success: #22C55E;
  --color-danger: #EF4444;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, 'Courier New', monospace;

  --header-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  font-family: var(--font-sans);
  font-size: 1.125rem;
  line-height: 1.7;
  color: var(--color-neutral-900);
  background: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, svg {
  display: block;
  max-width: 100%;
}

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

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

ul {
  list-style: none;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--color-neutral-100);
  padding: 0.15em 0.4em;
  border-radius: 4px;
}

/* --- Accessibility --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--color-primary);
  color: var(--color-white);
  padding: 0.5rem 1rem;
  border-radius: 0 0 6px 6px;
  z-index: 1000;
  font-size: 0.875rem;
  font-weight: 500;
}

.skip-link:focus {
  top: 0;
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* --- Layout --- */
.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

section {
  padding: 5rem 0;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.01em;
  text-align: center;
  margin-bottom: 0.75rem;
}

.section-subtitle {
  text-align: center;
  color: var(--color-neutral-700);
  font-size: 1.125rem;
  margin-bottom: 3rem;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  transition: background 0.2s, color 0.2s, border-color 0.2s, transform 0.1s;
  border: 2px solid transparent;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  color: var(--color-white);
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.btn-outline:hover {
  background: var(--color-primary);
  color: var(--color-white);
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* --- Header --- */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-neutral-200);
  height: var(--header-height);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.logo {
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
  display: flex;
}

.logo-gate {
  color: var(--color-neutral-900);
}

.logo-cha {
  color: var(--color-primary);
}

.logo:hover .logo-gate {
  color: var(--color-neutral-900);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-neutral-700);
  padding: 0.25rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-links a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-neutral-700);
  transition: color 0.2s;
}

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

.nav-links .btn-primary {
  color: var(--color-white);
}

.nav-links .btn-primary:hover {
  color: var(--color-white);
}

.nav-github {
  display: flex;
  align-items: center;
}

.nav-github svg {
  display: block;
}

/* --- Hero --- */
.hero {
  padding: 8rem 0 6rem;
  text-align: center;
}

.hero-content {
  max-width: 720px;
  margin: 0 auto;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 1.5rem;
}

.hero-description {
  font-size: 1.25rem;
  color: var(--color-neutral-700);
  line-height: 1.7;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.hero-badges {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  color: var(--color-neutral-400);
  font-size: 0.875rem;
  font-weight: 500;
}

.badge-separator {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-neutral-400);
}

/* --- Features --- */
.features {
  background: var(--color-neutral-50);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: var(--color-white);
  border-radius: 12px;
  padding: 2rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  transition: box-shadow 0.2s, transform 0.2s;
}

.feature-card:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--color-primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
  color: var(--color-primary);
}

.feature-card h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.feature-card p {
  font-size: 0.95rem;
  color: var(--color-neutral-700);
  line-height: 1.6;
}

/* --- How It Works --- */
.how-it-works {
  background: var(--color-white);
}

.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 1rem;
}

.step {
  flex: 1;
  max-width: 280px;
  text-align: center;
}

.step-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: var(--color-white);
  font-size: 1.25rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1rem;
}

.step h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.step p {
  font-size: 0.95rem;
  color: var(--color-neutral-700);
  line-height: 1.6;
}

.step-connector {
  display: flex;
  align-items: center;
  padding-top: 12px;
  color: var(--color-neutral-200);
  flex-shrink: 0;
}

/* --- Installation --- */
.install {
  background: var(--color-neutral-50);
}

.tabs {
  max-width: 720px;
  margin: 0 auto;
}

.tab-list {
  display: flex;
  gap: 0;
  border-bottom: 2px solid var(--color-neutral-200);
  margin-bottom: 1.5rem;
}

.tab-list button {
  background: none;
  border: none;
  padding: 0.75rem 1.25rem;
  font-size: 0.95rem;
  font-weight: 500;
  font-family: var(--font-sans);
  color: var(--color-neutral-400);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: color 0.2s, border-color 0.2s;
}

.tab-list button[aria-selected="true"] {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
  font-weight: 600;
}

.tab-list button:hover {
  color: var(--color-neutral-700);
}

.code-block {
  position: relative;
  background: var(--color-code-bg);
  border-radius: 8px;
  overflow: hidden;
}

.code-block pre {
  padding: 1.5rem;
  overflow-x: auto;
  margin: 0;
}

.code-block code {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--color-code-text);
  background: none;
  padding: 0;
  border-radius: 0;
}

.copy-btn {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: var(--color-code-text);
  padding: 0.3rem 0.75rem;
  border-radius: 6px;
  font-size: 0.8rem;
  font-family: var(--font-sans);
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s;
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.2);
}

.install-note {
  margin-top: 1rem;
  font-size: 0.9rem;
  color: var(--color-neutral-700);
}

.install-note code {
  font-size: 0.85em;
}

/* --- WordPress --- */
.wordpress {
  background: var(--color-white);
}

.wp-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.wp-description {
  font-size: 1.1rem;
  color: var(--color-neutral-700);
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.wp-features {
  margin-bottom: 2rem;
}

.wp-features li {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  font-size: 0.95rem;
  color: var(--color-neutral-700);
  line-height: 1.5;
}

.wp-features li svg {
  color: var(--color-success);
  flex-shrink: 0;
  margin-top: 2px;
}

.wp-forms-card {
  background: var(--color-neutral-50);
  border: 1px solid var(--color-neutral-200);
  border-radius: 12px;
  padding: 2rem;
}

.wp-forms-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  text-align: center;
  color: var(--color-primary-dark);
}

.wp-forms-group {
  margin-bottom: 1.25rem;
}

.wp-forms-group:last-child {
  margin-bottom: 0;
}

.wp-forms-group h4 {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-neutral-400);
  margin-bottom: 0.5rem;
}

.wp-forms-group ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.wp-forms-group li {
  background: var(--color-white);
  border: 1px solid var(--color-neutral-200);
  padding: 0.25rem 0.75rem;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-neutral-700);
}

/* --- Comparison --- */
.comparison {
  background: var(--color-neutral-50);
}

.table-wrapper {
  overflow-x: auto;
  border-radius: 12px;
  border: 1px solid var(--color-neutral-200);
  background: var(--color-white);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

thead {
  background: var(--color-code-bg);
  color: var(--color-white);
}

thead th {
  padding: 1rem 1.5rem;
  text-align: left;
  font-weight: 600;
  font-size: 0.95rem;
}

thead th:first-child {
  border-radius: 11px 0 0 0;
}

thead th:last-child {
  border-radius: 0 11px 0 0;
}

.col-gatecha {
  color: var(--color-primary-light);
}

tbody td {
  padding: 0.85rem 1.5rem;
  border-bottom: 1px solid var(--color-neutral-100);
  color: var(--color-neutral-700);
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: var(--color-neutral-50);
}

tbody td:first-child {
  font-weight: 500;
  color: var(--color-neutral-900);
}

tbody td strong {
  color: var(--color-primary-dark);
  font-weight: 600;
}

.icon-check {
  color: var(--color-success);
}

.icon-cross {
  color: var(--color-danger);
}

.comparison-note {
  text-align: center;
  margin-top: 1.5rem;
  font-size: 0.85rem;
  color: var(--color-neutral-400);
  font-style: italic;
}

/* --- FAQ --- */
.faq {
  background: var(--color-white);
}

.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--color-neutral-200);
}

.faq-item:first-child {
  border-top: 1px solid var(--color-neutral-200);
}

.faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 0;
  cursor: pointer;
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--color-neutral-900);
  list-style: none;
  user-select: none;
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-question::marker {
  content: "";
}

.faq-chevron {
  flex-shrink: 0;
  transition: transform 0.3s;
  color: var(--color-neutral-400);
}

.faq-item[open] .faq-chevron {
  transform: rotate(180deg);
}

.faq-answer {
  padding-bottom: 1.25rem;
  overflow: hidden;
}

.faq-answer p {
  font-size: 0.95rem;
  color: var(--color-neutral-700);
  line-height: 1.7;
}

/* --- Footer --- */
.footer {
  background: var(--color-code-bg);
  color: var(--color-neutral-400);
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand .logo {
  margin-bottom: 1rem;
}

.footer-brand .logo-gate {
  color: var(--color-white);
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 300px;
}

.footer-links h4 {
  color: var(--color-neutral-200);
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-links a {
  color: var(--color-neutral-400);
  font-size: 0.9rem;
  transition: color 0.2s;
}

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

.footer-privacy {
  margin-top: 1rem;
  font-size: 0.8rem;
  line-height: 1.5;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 2rem;
  text-align: center;
  font-size: 0.85rem;
}

/* ===========================
   Responsive
   =========================== */

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

@media (max-width: 768px) {
  section {
    padding: 3.5rem 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .section-subtitle {
    font-size: 1rem;
    margin-bottom: 2rem;
  }

  /* Nav */
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-white);
    border-bottom: 1px solid var(--color-neutral-200);
    flex-direction: column;
    padding: 1.5rem;
    gap: 1rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  }

  .nav-links.nav-open {
    display: flex;
  }

  .nav-links .btn-sm {
    text-align: center;
    justify-content: center;
  }

  /* Hero */
  .hero {
    padding: 5rem 0 4rem;
  }

  .hero-title {
    font-size: 2.25rem;
  }

  .hero-description {
    font-size: 1.05rem;
  }

  .hero-badges {
    flex-direction: column;
    gap: 0.5rem;
  }

  .badge-separator {
    display: none;
  }

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

  /* Steps */
  .steps {
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
  }

  .step {
    max-width: 100%;
  }

  .step-connector {
    transform: rotate(90deg);
    padding-top: 0;
  }

  /* Tabs */
  .tab-list {
    flex-wrap: wrap;
  }

  .tab-list button {
    padding: 0.5rem 0.75rem;
    font-size: 0.85rem;
  }

  /* WordPress */
  .wp-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  /* Comparison table */
  table {
    font-size: 0.85rem;
  }

  thead th,
  tbody td {
    padding: 0.65rem 1rem;
  }

  /* Footer */
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.85rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .hero-actions .btn {
    width: 100%;
    justify-content: center;
  }
}