/*
 * Cleanly — Landing Page
 * Light editorial, Swiss-influenced, technical journal feel.
 */

/* ============================================
   RESET
   ============================================ */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
img, picture, svg { display: block; max-width: 100%; }
button, input, textarea, select { font: inherit; }

/* ============================================
   DESIGN TOKENS
   ============================================ */

:root {
  --font-display: 'Instrument Serif', Georgia, serif;
  --font-body: 'Plus Jakarta Sans', system-ui, sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;

  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 32px;
  --spacing-xl: 48px;
  --spacing-2xl: 80px;
  --spacing-3xl: 120px;

  --width-max: 1140px;
  --width-content: 780px;

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out-expo: cubic-bezier(0.19, 1, 0.22, 1);
  --duration-fast: 0.15s;
  --duration-base: 0.3s;
  --duration-slow: 0.6s;

  /* Warm light palette */
  --color-bg: #F9F6F1;
  --color-surface: #F0EBE3;
  --color-surface-2: #E8E2D8;
  --color-border: #D8D0C4;
  --color-border-light: #E4DDD3;
  --color-text: #4A4239;
  --color-text-dim: #8A7F72;
  --color-text-muted: #B3A899;
  --color-ink: #1A1612;

  /* Accent — Brick Red */
  --color-accent: #C4432A;
  --color-accent-hover: #D95638;
  --color-accent-dim: rgba(196, 67, 42, 0.08);
  --color-accent-subtle: rgba(196, 67, 42, 0.04);

  /* Success — Deep Forest */
  --color-success: #2D7A4F;
  --color-success-dim: rgba(45, 122, 79, 0.08);

  /* Danger — for "before" states */
  --color-danger: #C4432A;
  --color-danger-dim: rgba(196, 67, 42, 0.08);

  /* Category colors — muted, editorial */
  --cat-write: #2D7A4F;
  --cat-harden: #C4432A;
  --cat-optimize: #B8860B;
  --cat-observe: #6B4FA0;
  --cat-quality: #2E6B9E;
  --cat-operate: #A0527A;
  --cat-understand: #2A7B8E;
}

/* ============================================
   BASE
   ============================================ */

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 400;
  line-height: 1.1;
  color: var(--color-ink);
}

a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color var(--duration-fast) var(--ease-out);
}

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

code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  padding: 0.15em 0.4em;
  background: var(--color-accent-dim);
  color: var(--color-accent);
  border-radius: 3px;
}

::selection {
  background: var(--color-accent);
  color: var(--color-bg);
}

/* ============================================
   SKIP LINK
   ============================================ */

.skip-link {
  position: absolute;
  top: -100%;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10000;
  padding: var(--spacing-sm) var(--spacing-lg);
  background: var(--color-ink);
  color: var(--color-bg);
  font-weight: 600;
  text-decoration: none;
  border-radius: 0 0 6px 6px;
  transition: top 0.2s ease;
}

.skip-link:focus { top: 0; color: var(--color-bg); }

/* ============================================
   GRAIN OVERLAY (hidden — clean aesthetic)
   ============================================ */

.grain-overlay { display: none; }

/* ============================================
   GITHUB LINK
   ============================================ */

.github-link {
  position: fixed;
  top: var(--spacing-md);
  right: var(--spacing-md);
  z-index: 100;
  color: var(--color-text-dim);
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

.github-link:hover { color: var(--color-ink); }

/* ============================================
   HERO
   ============================================ */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: var(--spacing-3xl) var(--spacing-lg) var(--spacing-2xl);
  position: relative;
}

.hero::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--color-border);
}

.hero-container {
  max-width: var(--width-max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--spacing-3xl);
  align-items: center;
  width: 100%;
}

.hero-title {
  font-size: clamp(4rem, 9vw, 7.5rem);
  letter-spacing: -0.04em;
  margin-bottom: var(--spacing-md);
  font-style: italic;
  line-height: 0.95;
}

.hero-tagline {
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  color: var(--color-accent);
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  letter-spacing: -0.01em;
}

.hero-inspired {
  font-size: 0.88rem;
  color: var(--color-text-dim);
  margin-bottom: var(--spacing-xl);
  font-style: italic;
}

.hero-description {
  font-size: 1.05rem;
  color: var(--color-text);
  line-height: 1.75;
  margin-bottom: var(--spacing-xl);
  max-width: 500px;
}

/* Stats */
.hero-stats {
  display: flex;
  align-items: baseline;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.stat { text-align: left; }

.stat-number {
  display: block;
  font-family: var(--font-display);
  font-size: 3rem;
  color: var(--color-ink);
  line-height: 1;
  font-style: italic;
}

.stat-label {
  font-size: 0.75rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 500;
}

.stat-divider {
  width: 1px;
  height: 32px;
  background: var(--color-border);
  align-self: center;
}

/* CTA */
.hero-cta-group {
  display: flex;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xl);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: 14px 32px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  text-decoration: none;
  transition: all var(--duration-base) var(--ease-out);
  cursor: pointer;
  border: none;
  letter-spacing: -0.01em;
}

.btn-primary {
  background: var(--color-ink);
  color: var(--color-bg);
}

.btn-primary:hover {
  background: #2E2820;
  color: var(--color-bg);
  transform: translateY(-1px);
  box-shadow: 0 8px 24px rgba(26, 22, 18, 0.15);
}

.btn-secondary {
  background: transparent;
  color: var(--color-ink);
  border: 1.5px solid var(--color-ink);
}

.btn-secondary:hover {
  background: var(--color-ink);
  color: var(--color-bg);
  transform: translateY(-1px);
}

/* Platforms */
.hero-platforms {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.platforms-label {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 500;
}

.platforms-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.platforms-row img {
  border-radius: 4px;
  opacity: 0.5;
  transition: opacity var(--duration-fast) var(--ease-out);
}

.platforms-row img:hover { opacity: 1; }

/* ============================================
   COMPARISON (Hero Right)
   ============================================ */

.comparison {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.comparison-panel {
  position: relative;
  border-radius: 8px;
  overflow: hidden;
}

.comparison-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  padding: 4px 10px;
  border-radius: 3px;
  z-index: 2;
  font-family: var(--font-mono);
}

.comparison-badge--before {
  background: var(--color-danger-dim);
  color: var(--color-danger);
}

.comparison-badge--after {
  background: var(--color-success-dim);
  color: var(--color-success);
}

.code-example {
  padding: var(--spacing-lg);
  padding-top: 44px;
  border-radius: 8px;
  overflow-x: auto;
}

.code-example--bad {
  background: var(--color-ink);
  border: none;
}

.code-example--good {
  background: var(--color-ink);
  border: none;
}

.code-example pre {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.75;
  color: #C8BFB4;
}

.code-example code {
  background: none;
  padding: 0;
  font-size: inherit;
  color: inherit;
}

.code-comment { color: #6B6259; }
.code-string { color: #7CB893; }
.code-keyword { color: #B0A0D0; }
.code-number { color: #D4A852; }

.code-callouts {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: var(--spacing-sm);
}

.callout {
  font-size: 0.65rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 3px;
  background: rgba(196, 67, 42, 0.15);
  color: #E8836E;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

/* ============================================
   SECTIONS (shared)
   ============================================ */

.site-content {
  position: relative;
}

.section {
  padding: var(--spacing-3xl) var(--spacing-lg);
  max-width: var(--width-max);
  margin: 0 auto;
}

.section + .section {
  border-top: 1px solid var(--color-border);
}

.section-header {
  margin-bottom: var(--spacing-xl);
}

.section-number {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-accent);
  margin-bottom: var(--spacing-xs);
  letter-spacing: 0.08em;
  font-weight: 500;
}

.section-title {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  letter-spacing: -0.03em;
  font-style: italic;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--color-text-dim);
  margin-top: var(--spacing-xs);
}

.section-lead {
  font-size: 1.15rem;
  color: var(--color-text);
  max-width: var(--width-content);
  margin-bottom: var(--spacing-xl);
  line-height: 1.75;
}

/* ============================================
   PROBLEM GRID
   ============================================ */

.problems-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  overflow: hidden;
}

.problem-card {
  background: var(--color-bg);
  padding: var(--spacing-lg);
  transition: background var(--duration-base) var(--ease-out);
}

.problem-card:hover {
  background: var(--color-surface);
}

.problem-icon {
  display: block;
  font-size: 1.3rem;
  margin-bottom: var(--spacing-sm);
  opacity: 0.8;
}

.problem-card h3 {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 6px;
  letter-spacing: -0.01em;
}

.problem-card p {
  font-size: 0.85rem;
  color: var(--color-text-dim);
  line-height: 1.6;
}

/* ============================================
   SKILLS SECTION
   ============================================ */

.skills-categories {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
}

.skill-category {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: var(--spacing-lg);
  align-items: start;
}

.category-title {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding-top: var(--spacing-md);
  position: sticky;
  top: var(--spacing-lg);
}

.category-title--write { color: var(--cat-write); }
.category-title--harden { color: var(--cat-harden); }
.category-title--optimize { color: var(--cat-optimize); }
.category-title--observe { color: var(--cat-observe); }
.category-title--quality { color: var(--cat-quality); }
.category-title--operate { color: var(--cat-operate); }
.category-title--understand { color: var(--cat-understand); }

.skill-cards {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.skill-card {
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--spacing-md) var(--spacing-lg);
  transition: border-color var(--duration-base) var(--ease-out), background var(--duration-base) var(--ease-out);
}

.skill-card:hover {
  border-color: var(--color-text-dim);
  background: var(--color-surface);
}

.skill-name {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-ink);
  margin-bottom: 4px;
}

.skill-desc {
  font-size: 0.88rem;
  color: var(--color-text-dim);
  line-height: 1.55;
}

.skill-card-top {
  margin-bottom: var(--spacing-sm);
}

.skill-example {
  padding-top: var(--spacing-sm);
  border-top: 1px solid var(--color-border-light);
}

.skill-example-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-text-muted);
  margin-bottom: 4px;
}

.skill-example-prompt {
  font-size: 0.85rem;
  color: var(--color-ink);
  font-style: italic;
  font-family: var(--font-display);
  margin-bottom: 4px;
}

.skill-example-result {
  font-size: 0.8rem;
  color: var(--color-text-dim);
  line-height: 1.55;
}

/* ============================================
   PRINCIPLES
   ============================================ */

.principles-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
}

.principle {
  padding: var(--spacing-lg) var(--spacing-xl);
  border-bottom: 1px solid var(--color-border);
  transition: background var(--duration-base) var(--ease-out);
}

.principle:nth-child(odd) {
  border-right: 1px solid var(--color-border);
}

.principle:nth-last-child(-n+2) {
  border-bottom: none;
}

.principle:hover {
  background: var(--color-surface);
}

.principle-number {
  font-family: var(--font-display);
  font-size: 2rem;
  color: var(--color-border);
  margin-bottom: var(--spacing-xs);
  display: block;
  line-height: 1;
  font-style: italic;
}

.principle h3 {
  font-size: 1.15rem;
  margin-bottom: var(--spacing-xs);
  font-style: italic;
}

.principle p {
  font-size: 0.88rem;
  color: var(--color-text-dim);
  line-height: 1.65;
}

/* ============================================
   INSTALL TERMINAL
   ============================================ */

.install-terminal {
  max-width: 640px;
  margin: 0 auto var(--spacing-xl);
}

.glass-terminal {
  background: var(--color-ink);
  border-radius: 8px;
  overflow: hidden;
}

.terminal-header {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 12px var(--spacing-md);
  border-bottom: 1px solid #2E2820;
}

.terminal-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.terminal-dot.red { background: #6B4A42; }
.terminal-dot.yellow { background: #6B6042; }
.terminal-dot.green { background: #426B4A; }

.terminal-title {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: #6B6259;
}

.terminal-body {
  padding: var(--spacing-md);
}

.install-row {
  padding: var(--spacing-sm) 0;
}

.install-label {
  display: block;
  font-size: 0.7rem;
  font-weight: 600;
  color: #6B6259;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
  font-family: var(--font-mono);
}

.install-cmd {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.terminal-prompt {
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-weight: 600;
}

.install-cmd code {
  background: none;
  padding: 0;
  color: #C8BFB4;
  font-size: 0.88rem;
}

.copy-btn {
  background: none;
  border: none;
  color: #6B6259;
  cursor: pointer;
  padding: 4px;
  border-radius: 3px;
  transition: color var(--duration-fast) var(--ease-out);
  margin-left: auto;
}

.copy-btn:hover {
  color: #C8BFB4;
}

.copy-btn.copied {
  color: #7CB893;
}

.install-note {
  display: block;
  font-size: 0.7rem;
  color: #5A5249;
  margin-top: 4px;
  font-family: var(--font-mono);
}

.install-divider {
  height: 1px;
  background: #2E2820;
  margin: var(--spacing-sm) 0;
}

/* Install platforms */
.install-platforms {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.platform-badges {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
}

.platform-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 0.8rem;
  color: var(--color-text-dim);
  font-weight: 500;
  transition: border-color var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out);
}

.platform-badge:hover {
  border-color: var(--color-text-dim);
  color: var(--color-ink);
}

.platform-badge img {
  border-radius: 3px;
}

/* ============================================
   FAQ
   ============================================ */

.faq-list {
  max-width: var(--width-content);
  display: flex;
  flex-direction: column;
}

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

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

.faq-question {
  padding: var(--spacing-md) 0;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  color: var(--color-ink);
  list-style: none;
  transition: color var(--duration-fast) var(--ease-out);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

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

.faq-question::after {
  content: '+';
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--color-text-muted);
  margin-left: auto;
  transition: transform var(--duration-base) var(--ease-out);
  font-style: italic;
}

.faq-question::before { display: none; }

details[open] .faq-question::after {
  content: '\2212';
  color: var(--color-accent);
}

.faq-question:hover {
  color: var(--color-accent);
}

.faq-answer {
  padding: 0 0 var(--spacing-md);
  color: var(--color-text-dim);
  line-height: 1.75;
  max-width: 600px;
}

.faq-answer p { margin-bottom: var(--spacing-sm); }
.faq-answer p:last-child { margin-bottom: 0; }

/* ============================================
   FOOTER
   ============================================ */

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) var(--spacing-lg);
  margin-top: var(--spacing-2xl);
}

.footer-content {
  max-width: var(--width-max);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: var(--spacing-lg);
}

.footer-logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-style: italic;
  color: var(--color-ink);
  text-decoration: none;
}

.footer-tagline {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-top: 4px;
}

.footer-links {
  display: flex;
  gap: var(--spacing-md);
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--color-text-dim);
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

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

.footer-bottom {
  max-width: var(--width-max);
  margin: 0 auto;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.footer-bottom a {
  color: var(--color-text-dim);
}

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

.footer-divider { color: var(--color-border); }

/* ============================================
   REVEAL ANIMATIONS
   ============================================ */

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--duration-slow) var(--ease-out-expo), transform var(--duration-slow) var(--ease-out-expo);
}

[data-reveal].revealed {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children */
[data-reveal]:nth-child(2) { transition-delay: 0.08s; }
[data-reveal]:nth-child(3) { transition-delay: 0.16s; }

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 1024px) {
  .hero-container {
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
  }

  .hero-right {
    max-width: 600px;
  }

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

@media (max-width: 768px) {
  .hero {
    min-height: auto;
    padding: var(--spacing-xl) var(--spacing-md);
    padding-top: var(--spacing-2xl);
  }

  .section {
    padding: var(--spacing-2xl) var(--spacing-md);
  }

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

  .skill-category {
    grid-template-columns: 1fr;
    gap: var(--spacing-sm);
  }

  .category-title {
    position: static;
    padding-top: 0;
  }

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

  .principle {
    border-right: none !important;
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
  }

  .principle:nth-last-child(2) {
    border-bottom: 1px solid var(--color-border);
  }

  .hero-stats {
    gap: var(--spacing-lg);
  }

  .stat-number {
    font-size: 2.2rem;
  }

  .footer-content {
    flex-direction: column;
    gap: var(--spacing-md);
  }

  .footer-links {
    flex-wrap: wrap;
  }

  .hero-cta-group {
    flex-direction: column;
  }

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

  .footer-bottom {
    flex-wrap: wrap;
  }
}

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

  [data-reveal] {
    opacity: 1;
    transform: none;
  }

  html { scroll-behavior: auto; }
}