/* ============================================
   QUDOS — Premium Stationery Design System
   Optimized for PageSpeed, Accessibility & UX
   ============================================ */

/* ---------- CSS Custom Properties ---------- */
:root {
  --paper: #f7f5f0;
  --paper-light: #faf9f6;
  --paper-warm: #f0ece3;
  --sand: #d4c4a8;
  --sand-light: #e8dfc8;
  --graphite: #2c2c2c;
  --graphite-soft: #4a4a4a;
  --ink: #1f1f1f;
  --green: #6b7c5c;
  --green-dark: #4e5c42;
  --green-muted: #8a9a7a;
  --border: #e0d8c8;
  --line: #e8e0d0;
  --rule: #d6cbb6;
  --sticky-yellow: #f3e9a9;
  --sticky-green: #d4e4c4;
  --sticky-sand: #ece2cc;
  --shadow-soft: rgba(44, 44, 44, 0.05);
  --shadow-medium: rgba(44, 44, 44, 0.1);
  --shadow-strong: rgba(44, 44, 44, 0.14);
  --font-serif: Georgia, Cambria, "Times New Roman", Times, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "Courier New", Courier, monospace;
  --max-width: 1160px;
  --radius: 3px;
  --radius-lg: 6px;
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--graphite);
  background-color: var(--paper);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

img {
  font-style: italic;
}

a {
  color: var(--green-dark);
  text-decoration: underline;
  text-decoration-color: var(--sand);
  text-underline-offset: 3px;
  transition: color var(--transition-fast), text-decoration-color var(--transition-fast);
}

a:hover {
  color: var(--ink);
  text-decoration-color: var(--graphite);
}

a:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 3px;
  border-radius: 2px;
}

::selection {
  background-color: var(--sticky-yellow);
  color: var(--ink);
}

/* ---------- Typography ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-serif);
  color: var(--ink);
  line-height: 1.15;
  font-weight: 600;
  letter-spacing: -0.015em;
  text-wrap: balance;
}

h1 { font-size: clamp(2.2rem, 5.2vw, 3.6rem); }
h2 { font-size: clamp(1.5rem, 3.2vw, 2.2rem); }
h3 { font-size: clamp(1.15rem, 2.2vw, 1.4rem); }
h4 { font-size: 1.05rem; }

p {
  margin-bottom: 1.25em;
  max-width: 68ch;
}

.lead {
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 1.8vw, 1.3rem);
  line-height: 1.65;
  color: var(--graphite-soft);
}

.label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--green);
  margin-bottom: 0.85rem;
  display: block;
}

/* ---------- Layout ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
  content-visibility: auto;
  contain-intrinsic-size: 0 500px;
}

.section:first-of-type {
  content-visibility: visible;
}

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

/* ---------- Skip Link ---------- */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--ink);
  color: var(--paper);
  padding: 0.5rem 1rem;
  z-index: 1000;
  font-size: 0.85rem;
  text-decoration: none;
  transition: top var(--transition-fast);
}

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

/* ---------- Header ---------- */
.site-header {
  background-color: rgba(250, 249, 246, 0.96);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;


}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand {
  font-family: var(--font-serif);
  font-size: 1.55rem;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.02em;
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.25rem 0;
}

.brand:hover {
  color: var(--green-dark);
}

.brand-mark {
  width: 28px;
  height: 28px;
  display: inline-block;
  flex-shrink: 0;
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 2.25rem;
}

.main-nav a {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--graphite-soft);
  text-decoration: none;
  padding: 0.35rem 0;
  position: relative;
}

.main-nav a::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--green);
  transition: width var(--transition-base);
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--ink);
}

.main-nav a:hover::after,
.main-nav a[aria-current="page"]::after {
  width: 100%;
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--graphite);
}

.menu-toggle:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- Hero ---------- */
.hero {
  background-color: var(--paper);
  padding: 5.5rem 0 4.5rem;
  position: relative;
  overflow: hidden;
  content-visibility: visible;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    to bottom,
    transparent,
    transparent 31px,
    var(--line) 31px,
    var(--line) 32px
  );
  opacity: 0.35;
  pointer-events: none;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  position: relative;
  z-index: 1;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 4.5rem;
  align-items: center;
}

.hero-title {
  font-size: clamp(2.3rem, 5.2vw, 3.6rem);
  line-height: 1.08;
  margin-bottom: 1.35rem;
}

.hero-title em {
  font-style: italic;
  color: var(--green-dark);
}

.hero-lead {
  font-size: 1.15rem;
  color: var(--graphite-soft);
  max-width: 52ch;
  margin-bottom: 2.25rem;
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-visual svg {
  width: 100%;
  max-width: 360px;
  height: auto;
}

/* ---------- Paper Card ---------- */
.paper-card {
  background-color: var(--paper-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  position: relative;
  box-shadow: 0 1px 4px var(--shadow-soft), 0 6px 20px var(--shadow-soft);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.paper-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--shadow-soft), 0 12px 28px var(--shadow-soft);
}

.paper-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 24px;
  width: 2px;
  height: 100%;
  background-color: var(--rule);
  opacity: 0.5;
}

/* ---------- Sticky Notes ---------- */
.sticky-note {
  padding: 1.5rem;
  border-radius: 2px;
  position: relative;
  box-shadow: 2px 3px 10px var(--shadow-medium);
  transform: rotate(-0.5deg);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.sticky-note:hover {
  transform: rotate(0deg) translateY(-3px);
  box-shadow: 3px 5px 14px var(--shadow-medium);
}

.sticky-note.yellow { background-color: var(--sticky-yellow); }
.sticky-note.green { background-color: var(--sticky-green); transform: rotate(0.5deg); }
.sticky-note.green:hover { transform: rotate(0deg) translateY(-3px); }
.sticky-note.sand { background-color: var(--sticky-sand); transform: rotate(-1deg); }
.sticky-note.sand:hover { transform: rotate(0deg) translateY(-3px); }

.sticky-note h4 {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
}

.sticky-note p {
  font-size: 0.92rem;
  margin: 0;
  color: var(--graphite-soft);
  line-height: 1.55;
}

/* ---------- Notebook Divider ---------- */
.notebook-divider {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 3.5rem 0;
}

.notebook-divider .line {
  flex: 1;
  height: 1px;
  background-color: var(--rule);
}

.notebook-divider .spiral {
  display: flex;
  gap: 6px;
}

.notebook-divider .spiral span {
  width: 6px;
  height: 10px;
  border: 1.5px solid var(--rule);
  border-radius: 50%;
  display: inline-block;
}

/* ---------- Grids ---------- */
.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: 1.75rem;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ---------- Category Cards ---------- */
.category-card {
  background-color: var(--paper-light);
  border: 1px solid var(--border);
  padding: 2rem 1.5rem;
  text-align: center;
  border-radius: var(--radius);
  transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
  position: relative;
}

.category-card::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 10%;
  width: 80%;
  height: 2px;
  background-color: var(--green-muted);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.category-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px var(--shadow-soft);
  border-color: var(--sand);
}

.category-card:hover::after {
  opacity: 1;
}

.category-icon {
  width: 44px;
  height: 44px;
  margin: 0 auto 1rem;
  color: var(--green-dark);
}

.category-card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.category-card p {
  font-size: 0.88rem;
  color: var(--graphite-soft);
  margin: 0 auto;
  line-height: 1.55;
}

/* ---------- Workspace Diagram ---------- */
.workspace-diagram {
  background-color: var(--paper-warm);
  border: 1px solid var(--border);
  padding: 2.5rem;
  border-radius: var(--radius);
}

.workspace-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.workspace-item {
  text-align: center;
  padding: 1.5rem 1rem;
  background: var(--paper-light);
  border: 1px dashed var(--sand);
  border-radius: var(--radius);
  transition: transform var(--transition-base), border-color var(--transition-base);
}

.workspace-item:hover {
  transform: translateY(-2px);
  border-color: var(--green-muted);
}

.workspace-item svg {
  width: 36px;
  height: 36px;
  margin: 0 auto 0.75rem;
  color: var(--green-dark);
}

/* ---------- Educational Cards ---------- */
.edu-card {
  background-color: var(--paper-light);
  border: 1px solid var(--border);
  padding: 1.75rem;
  border-radius: var(--radius);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.edu-card:hover {
  box-shadow: 0 6px 20px var(--shadow-soft);
  transform: translateY(-2px);
}

.edu-card h3 {
  margin-bottom: 0.5rem;
  font-size: 1.15rem;
}

.edu-card .meta {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  color: var(--green);
  margin-bottom: 0.75rem;
  display: block;
  letter-spacing: 0.1em;
}

.edu-card p {
  font-size: 0.93rem;
  color: var(--graphite-soft);
  margin: 0;
  line-height: 1.6;
}

/* ---------- Product Cards ---------- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.product-card {
  background-color: var(--paper-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  display: flex;
  flex-direction: column;
  will-change: transform;
}

.product-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px var(--shadow-soft);
}

.product-image {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  background-color: var(--paper-warm);
  border-bottom: 1px solid var(--border);
  transition: transform var(--transition-slow);
}

.product-card:hover .product-image {
  transform: scale(1.02);
}

.product-info {
  padding: 1.35rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.product-info h3 {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
  font-family: var(--font-serif);
}

.product-info p {
  font-size: 0.88rem;
  color: var(--graphite-soft);
  margin: 0;
  line-height: 1.6;
}

/* ---------- FAQ ---------- */
.faq-item {
  border-bottom: 1px solid var(--line);
  padding: 1.75rem 0;
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-item h3 {
  font-size: 1.1rem;
  margin-bottom: 0.75rem;
}

.faq-item p {
  color: var(--graphite-soft);
  margin: 0;
  line-height: 1.65;
}

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.contact-block {
  background-color: var(--paper-light);
  border: 1px solid var(--border);
  padding: 2.25rem;
  border-radius: var(--radius);
}

.contact-block h3 {
  margin-bottom: 1.25rem;
  font-size: 1.25rem;
}

.contact-detail {
  margin-bottom: 1.25rem;
  display: flex;
  align-items: flex-start;
  gap: 0.85rem;
}

.contact-detail svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--green-dark);
  margin-top: 3px;
}

.contact-detail strong {
  display: block;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--graphite-soft);
  margin-bottom: 0.2rem;
}

.contact-detail span {
  color: var(--ink);
}

/* ---------- Footer ---------- */
.site-footer {
  background-color: var(--paper-warm);
  border-top: 1px solid var(--border);
  padding: 3.5rem 0 2.25rem;
  margin-top: 2rem;
  content-visibility: auto;
  contain-intrinsic-size: 0 400px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 2.5rem;
}

.footer-brand {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 0.85rem;
  display: block;
  text-decoration: none;
}

.footer-brand:hover {
  color: var(--green-dark);
}

.footer-about {
  font-size: 0.88rem;
  color: var(--graphite-soft);
  max-width: 32ch;
  line-height: 1.65;
}

.footer-col h4 {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 1.1rem;
  color: var(--graphite-soft);
  font-weight: 600;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 0.55rem;
}

.footer-col a {
  font-size: 0.88rem;
  color: var(--graphite-soft);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-col a:hover {
  color: var(--ink);
  text-decoration: underline;
}

.footer-disclaimer {
  border-top: 1px solid var(--line);
  padding-top: 1.75rem;
  font-size: 0.78rem;
  color: var(--graphite-soft);
  line-height: 1.55;
}

.footer-bottom {
  border-top: 1px solid var(--line);
  margin-top: 1.75rem;
  padding-top: 1.75rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.78rem;
  color: var(--graphite-soft);
}

/* ---------- Cookie Banner ---------- */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: rgba(250, 249, 246, 0.98);
  border-top: 2px solid var(--sand);
  padding: 1.25rem 1.5rem;
  box-shadow: 0 -4px 24px var(--shadow-medium);
  z-index: 200;
  transform: translateY(100%);
  transition: transform var(--transition-slow);


}

.cookie-banner.show {
  transform: translateY(0);
}

.cookie-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.cookie-text {
  font-size: 0.88rem;
  color: var(--graphite);
  line-height: 1.5;
}

.cookie-text a {
  color: var(--green-dark);
  text-decoration: underline;
}

.cookie-actions {
  display: flex;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.4rem;
  font-family: var(--font-sans);
  font-size: 0.84rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background-color var(--transition-fast), transform 0.1s ease, box-shadow var(--transition-fast);
  text-decoration: none;
  border: none;
  letter-spacing: 0.01em;
  line-height: 1.4;
  min-height: 42px;
}

.btn:active {
  transform: scale(0.98);
}

.btn:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 2px;
}

.btn-primary {
  background-color: var(--green);
  color: #fff;
  box-shadow: 0 1px 3px var(--shadow-soft);
}

.btn-primary:hover {
  background-color: var(--green-dark);
  color: #fff;
  box-shadow: 0 3px 8px var(--shadow-soft);
}

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

.btn-secondary:hover {
  background-color: var(--paper-warm);
  color: var(--ink);
  border-color: var(--sand);
}

/* ---------- Utility ---------- */
.text-center { text-align: center; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.mt-2 { margin-top: 2rem; }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- Reveal Animation ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

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

/* ---------- Sketch Lines ---------- */
.sketch-line {
  display: block;
  width: 100%;
  height: 1px;
  background-image: linear-gradient(to right, var(--rule) 50%, transparent 50%);
  background-size: 8px 1px;
  margin: 2.5rem 0;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .hero-grid,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

  .section {
    padding: 3.5rem 0;
  }
}

@media (max-width: 640px) {
  .grid-2,
  .grid-3,
  .grid-4,
  .workspace-grid,
  .product-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }

  .cookie-inner {
    flex-direction: column;
    text-align: center;
  }

  .menu-toggle {
    display: block;
    min-height: 44px;
    min-width: 44px;
  }

  .main-nav {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background-color: rgba(250, 249, 246, 0.98);
    border-bottom: 1px solid var(--border);
    padding: 1rem 1.5rem;
    display: none;
  
  
  }

  .main-nav.open {
    display: block;
  }

  .main-nav ul {
    flex-direction: column;
    gap: 0.75rem;
  }

  .main-nav a {
    display: block;
    padding: 0.6rem 0;
    font-size: 1rem;
  }

  .hero {
    padding: 3.5rem 0;
  }

  .section {
    padding: 2.75rem 0;
  }

  .paper-card,
  .contact-block,
  .workspace-diagram {
    padding: 1.5rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

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

/* ---------- Print ---------- */
@media print {
  .site-header,
  .site-footer,
  .cookie-banner,
  .menu-toggle {
    display: none;
  }

  .section {
    content-visibility: visible;
    padding: 1.5rem 0;
  }
}