:root {
  --radius-sm: 0.4rem;
  --radius-md: 0.9rem;
  --radius-lg: 1.6rem;
  --space-1: 0.45rem;
  --space-2: 0.85rem;
  --space-3: 1.5rem;
  --space-4: 2.4rem;
  --space-5: 3.4rem;
  --space-6: 4.6rem;
  --max-width: 1180px;
  --side-toggle-size: 40px;
  --side-toggle-icon-scale: 0.7;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0f111a;
  --surface: #161a25;
  --surface-alt: #1d2130;
  --text: #f5f6ff;
  --muted: #b4b9cb;
  --border: rgba(255, 255, 255, 0.14);
  --accent: #7d8dff;
  --accent-strong: #a2afff;
  --accent-soft: rgba(125, 141, 255, 0.18);
  --shadow-sm: 0 20px 45px rgba(0, 0, 0, 0.55);
  --shadow-md: 0 40px 95px rgba(0, 0, 0, 0.65);
}

html[data-theme="light"] {
  color-scheme: light;
  --bg: #f5f6fb;
  --surface: #ffffff;
  --surface-alt: #f9faff;
  --text: #111322;
  --muted: #5c6174;
  --border: #e0e4ef;
  --accent: #485bff;
  --accent-strong: #2437ff;
  --accent-soft: rgba(72, 91, 255, 0.12);
  --shadow-sm: 0 16px 45px rgba(15, 18, 40, 0.08);
  --shadow-md: 0 30px 70px rgba(15, 18, 40, 0.16);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

p {
  margin: 0 0 var(--space-2);
}

ul, ol {
  margin: 0 0 var(--space-2) var(--space-3);
  padding: 0;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 160ms ease, opacity 160ms ease;
}

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

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
}

.container {
  width: min(100%, var(--max-width));
  margin: 0 auto;
  padding: 0 var(--space-3);
}

.section {
  padding: var(--space-5) 0;
  scroll-margin-top: 5.5rem;
}

.section-alt {
  background: linear-gradient(180deg, transparent, rgba(255, 255, 255, 0.35));
}

.section-heading {
  max-width: 720px;
}

.section-heading h2 {
  margin: 0 0 var(--space-1);
  font-size: 2rem;
}

.section-intro {
  color: var(--muted);
  font-size: 1.05rem;
}

.section-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  box-shadow: var(--shadow-sm);
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.78rem;
  color: var(--muted);
  margin-bottom: var(--space-1);
}

.site-header {
  position: sticky;
  top: 0;
  width: 100%;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(14px);
  box-shadow: 0 10px 30px rgba(15, 18, 40, 0.06);
  z-index: 50;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-1) 0;
  gap: var(--space-2);
}

.logo a {
  font-weight: 600;
  color: var(--text);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.main-nav {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.main-nav a {
  padding: 0.35rem 0.8rem;
  border-radius: var(--radius-sm);
  color: var(--text);
  color: color-mix(in srgb, var(--text) 86%, transparent);
  opacity: 0.9;
  transition: background 160ms ease, color 160ms ease, opacity 160ms ease;
}

.main-nav a:hover,
.main-nav a:focus-visible {
  color: var(--accent-strong);
  background: var(--accent-soft);
  opacity: 1;
}

.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.theme-toggle:hover {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.theme-toggle:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent) 55%, transparent);
  outline-offset: 2px;
}

.theme-toggle__icon {
  display: block;
  width: 20px;
  height: 20px;
}

.btn-primary,
.btn-secondary,
.btn-ghost,
.btn-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 0.65rem 1.4rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid transparent;
  transition: transform 140ms ease, box-shadow 140ms ease, background-color 140ms ease;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: var(--surface);
  color: var(--accent);
  border-color: var(--accent);
}

.btn-secondary:hover {
  background: var(--accent-soft);
}

.btn-ghost {
  background: transparent;
  color: var(--muted);
  border-color: var(--border);
}

.btn-ghost:hover {
  background: var(--surface-alt);
  color: var(--accent-strong);
}

.btn-link {
  padding: 0;
  color: var(--accent);
}

.hero {
  padding: var(--space-6) 0 var(--space-5);
}

.hero-panel {
  background: radial-gradient(circle at 0% 0%, rgba(170, 204, 255, 0.4), var(--surface));
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

.hero-text h1 {
  margin: 0 0 var(--space-2);
  font-size: clamp(2rem, 3vw, 3.1rem);
  line-height: 1.2;
}

.hero-subtitle {
  margin-bottom: var(--space-3);
  color: var(--muted);
  max-width: 680px;
}

.hero-chips {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.chip {
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  font-size: 0.9rem;
  color: var(--muted);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-3);
  margin-top: var(--space-4);
}

.project-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 140ms ease, box-shadow 140ms ease;
}

.project-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}

.project-link {
  display: flex;
  flex-direction: column;
  height: 100%;
  color: inherit;
}

.project-thumb {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--surface-alt);
}

.case-card-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.project-content {
  padding: var(--space-3);
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.project-content h3 {
  margin: 0;
}

.project-tagline {
  color: var(--muted);
  margin: 0;
}

.project-meta {
  font-size: 0.85rem;
  color: var(--muted);
  margin: 0;
}

.project-cta {
  margin-top: auto;
  color: var(--accent);
  font-weight: 600;
}

.contact-panel .section-heading {
  margin-bottom: var(--space-3);
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: var(--space-2) 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
  color: var(--muted);
}

.case-main {
  padding-bottom: var(--space-5);
}

.case-hero {
  padding: var(--space-5) 0;
}

.case-hero-inner {
  background: radial-gradient(circle at top left, rgba(170, 204, 255, 0.45), var(--surface));
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-3);
  align-items: center;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

.case-hero-text h1 {
  margin: 0 0 var(--space-1);
  font-size: clamp(2rem, 3vw, 2.6rem);
}

.case-goal {
  color: var(--muted);
}

.case-hero-image img,
.hero-media__img {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.case-hero-link {
  grid-column: 1 / -1;
  text-align: right;
  font-weight: 600;
}

.case-hero-link a {
  color: var(--accent-strong);
}

.case-layout {
  margin-top: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.case-body {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.case-body > .section {
  padding: 0;
}

.case-body > .section.section-alt {
  background: transparent;
}

.case-section {
  width: 100%;
  max-width: 100%;
  margin: 0;
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}

.case-section h2 {
  margin-top: 0;
}

.case-overview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-3);
  align-items: start;
}

.overview-table dl {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--space-2);
}

.overview-table dt {
  font-weight: 600;
  color: var(--muted);
}

.overview-table dd {
  margin: 0.2rem 0 0;
}

.project-name-highlight {
  color: var(--accent-strong);
  font-weight: 600;
}

.problem-goal-block {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-2);
  margin: var(--space-3) 0;
}

.problem-box,
.goal-box {
  border-radius: var(--radius-md);
  padding: var(--space-3);
  border: 1px solid var(--border);
  background: var(--accent-soft);
  box-shadow: var(--shadow-sm);
}

.problem-box h3,
.goal-box h3 {
  margin-top: 0;
}

.bullet-list {
  padding-left: var(--space-3);
}

.design-stack {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-2);
  margin: var(--space-3) 0;
}

.design-card {
  padding: var(--space-3);
  border-radius: var(--radius-md);
  background: var(--surface-alt);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 200ms ease, box-shadow 200ms ease;
}

.design-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}

.notebook-section {
  text-align: center;
}

.sketch-deck {
  position: relative;
  width: 320px;
  height: 220px;
  margin: var(--space-3) auto 0;
  cursor: pointer;
}

.sketch-card {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300px;
  transform-origin: center;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.sketch-card-1 { transform: translate(-50%, -50%) rotate(-2deg) scale(0.8); }
.sketch-card-2 { transform: translate(-50%, -50%) rotate(1deg) scale(0.78); }
.sketch-card-3 { transform: translate(-50%, -50%) rotate(-1.5deg) scale(0.76); }
.sketch-card-4 { transform: translate(-50%, -50%) rotate(2deg) scale(0.74); }

.centered-note {
  margin-top: var(--space-2);
  text-align: center;
  color: var(--muted);
}

.ideation-decisions {
  text-align: left;
}

.placeholder-image {
  border-radius: var(--radius-md);
  background: var(--surface-alt);
  border: 1px dashed var(--border);
  padding: var(--space-2);
}

.placeholder-image.small {
  min-height: 140px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.copy-states-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-2);
  margin: var(--space-3) 0;
}

.figure-note {
  margin-top: 0.4rem;
  font-size: 0.85rem;
  text-align: center;
  color: var(--muted);
}

.popup-menu-screenshot {
  margin: var(--space-3) auto;
  max-width: 420px;
  text-align: center;
}

body.case-virgin .popup-menu-screenshot {
  max-width: 756px;
}

body.case-virgin .popup-menu-screenshot img {
  width: 100%;
  height: auto;
}

.case-figure {
  margin: var(--space-3) auto;
  text-align: center;
}

.case-figure--phone {
  max-width: 420px;
}

.case-figure figcaption {
  margin-top: 0.35rem;
  font-size: 0.9rem;
  color: var(--muted);
}

.case-compare {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-2);
  align-items: start;
}

.test-card {
  border-radius: var(--radius-md);
  border: 1px dashed var(--border);
  padding: var(--space-3);
  background: var(--surface-alt);
}

.case-emulator {
  background: linear-gradient(180deg, var(--surface), var(--surface-alt));
}

.emulator-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-3);
  align-items: stretch;
}

.emulator-sample {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  background: var(--surface);
  font-family: "JetBrains Mono", "SFMono-Regular", Menlo, monospace;
  white-space: pre-wrap;
  line-height: 1.6;
}

.emulator-panel {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}

.emulator-panel h3 {
  margin-top: 0;
  color: var(--accent);
}

.emulator-option {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-1) 0;
  border-bottom: 1px solid var(--border);
}

.emulator-option:last-child {
  border-bottom: none;
}

.option-label {
  font-size: 0.9rem;
}

.switch {
  position: relative;
  display: inline-block;
  width: 46px;
  height: 26px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--accent);
  transition: 0.3s;
  border-radius: 26px;
}

.slider::before {
  content: "";
  position: absolute;
  height: 20px;
  width: 20px;
  left: 3px;
  bottom: 3px;
  background: #fff;
  transition: 0.3s;
  border-radius: 50%;
  transform: translateX(18px);
}

input:not(:checked) + .slider {
  background: var(--border);
}

input:not(:checked) + .slider::before {
  transform: translateX(0);
}

.ss-select-copy-button {
  position: absolute;
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 0.25rem 0.75rem;
  font-size: 0.8rem;
  cursor: pointer;
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  box-shadow: var(--shadow-sm);
  font-weight: 600;
  opacity: 0.85;
  transition: transform 200ms ease, opacity 200ms ease;
}

.ss-select-copy-button:hover {
  transform: scale(1.05);
  opacity: 1;
}

.ss-select-copy-button.copied {
  background: #10b981;
}

.weekly-users-charts {
  display: grid;
  gap: var(--space-3);
  margin-top: var(--space-3);
}

.chart-block {
  text-align: center;
}

.chart-block img {
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.links-list {
  list-style: disc;
  color: var(--accent);
}

.links-list a {
  color: var(--accent);
}

.links-list a:hover {
  text-decoration: underline;
}

.table-wrapper {
  overflow-x: auto;
  margin: var(--space-3) 0;
}

.metrics-table {
  width: 100%;
  border-collapse: collapse;
}

.metrics-table th,
.metrics-table td {
  text-align: left;
  padding: 0.65rem;
  border-bottom: 1px solid var(--border);
}

.metrics-table thead {
  background: var(--surface-alt);
}

.section-back {
  padding-top: 0;
}

.back-link-wrapper {
  display: flex;
}

.text-gap-sm {
  margin-top: var(--space-2);
}

.case-side-nav {
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  padding: var(--space-4) var(--space-3) var(--space-3);
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: box-shadow 200ms ease, opacity 200ms ease, transform 200ms ease;
}

.case-side-nav-toggle {
  position: absolute;
  top: var(--space-2);
  right: var(--space-2);
  width: var(--side-toggle-size);
  height: var(--side-toggle-size);
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-alt);
  color: var(--text);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease;
}

.case-side-nav-toggle-icon {
  display: inline-block;
  line-height: 1;
  font-size: calc(var(--side-toggle-size) * var(--side-toggle-icon-scale));
  transform-origin: 50% 50%;
  transition: transform 200ms ease;
  transform: rotate(0deg);
}

.case-side-nav-toggle:hover {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.case-side-nav-inner {
  margin-top: var(--space-3);
  transition: max-height 300ms ease, opacity 200ms ease, transform 200ms ease;
}

.case-side-nav-title {
  margin: 0 0 var(--space-2);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.case-side-nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.case-side-nav-link {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 0.6rem;
  border-radius: var(--radius-sm);
  color: var(--muted);
  transition: background 160ms ease, color 160ms ease;
}

.case-side-nav-link::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--border);
}

.case-side-nav-link:hover {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.case-side-nav-link.is-active {
  background: rgba(72, 91, 255, 0.15);
  color: var(--accent-strong);
  font-weight: 600;
}

.case-side-nav-link.is-active::before {
  background: var(--accent-strong);
}

.case-side-nav.is-collapsed .case-side-nav-inner {
  max-height: 0;
  opacity: 0;
  transform: translateY(-0.5rem);
  pointer-events: none;
}

.case-side-nav.is-faded {
  opacity: 0.75;
}

.case-side-nav.is-collapsed .case-side-nav-toggle-icon {
  transform: rotate(180deg);
}

@media (min-width: 1024px) {
  .case-layout {
    display: grid;
    grid-template-columns: minmax(0, 280px) minmax(0, 1fr);
    align-items: flex-start;
    gap: var(--space-4);
  }

  .case-side-nav {
    position: sticky;
    top: var(--space-4);
  }
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero-panel {
    padding: var(--space-3);
  }

  .sketch-deck {
    transform: scale(0.9);
  }
}