/*
  ============================================
  Version 1 Design System
  Shared variables and reusable components
  ============================================
*/

:root {
  --color-background: #ffffff;
  --color-surface: #f6f9fb;
  --color-surface-strong: #edf3f6;
  --color-surface-muted: #f9fbfc;
  --color-text: #182330;
  --color-text-muted: #4e5f70;
  --color-heading: #0f2740;
  --color-primary: #163a63;
  --color-primary-dark: #102d4d;
  --color-accent: #6fa68a;
  --color-accent-soft: #e7f1eb;
  --color-border: #d6e0e7;
  --color-border-strong: #c2d0da;
  --color-focus: rgba(22, 58, 99, 0.18);

  --font-family-base: Inter, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --font-size-hero: clamp(2.5rem, 5vw, 4.25rem);
  --font-size-h1: clamp(2.1rem, 4vw, 3.15rem);
  --font-size-h2: clamp(1.65rem, 3vw, 2.35rem);
  --font-size-h3: clamp(1.15rem, 2vw, 1.35rem);
  --font-size-body: 1rem;
  --font-size-large: 1.125rem;
  --font-size-small: 0.95rem;
  --line-height-body: 1.8;
  --line-height-heading: 1.15;

  --space-2xs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 5rem;

  --radius-sm: 0.5rem;
  --radius-md: 0.85rem;
  --radius-lg: 1.25rem;
  --radius-round: 999px;

  --shadow-soft: 0 12px 32px rgba(15, 39, 64, 0.06);
  --shadow-card: 0 10px 28px rgba(15, 39, 64, 0.05);
  --shadow-hover: 0 16px 36px rgba(15, 39, 64, 0.08);

  --container-width: 1120px;
  --header-height: 5rem;
  --reading-width: 68ch;
  --transition-base: 0.24s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-family-base);
  font-size: var(--font-size-body);
  line-height: var(--line-height-body);
  color: var(--color-text);
  background: var(--color-background);
}

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

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
textarea,
select {
  font: inherit;
}

:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  top: 0.75rem;
  left: 1rem;
  z-index: 2000;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-round);
  background: var(--color-primary);
  color: #ffffff;
  transform: translateY(-160%);
  transition: transform var(--transition-base);
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(100% - 2.5rem, var(--container-width));
  margin: 0 auto;
}

.narrow {
  max-width: 760px;
}

.section {
  padding: clamp(4rem, 8vw, 6rem) 0;
}

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

.section-soft {
  background: linear-gradient(180deg, var(--color-background) 0%, var(--color-surface-muted) 100%);
}

.section-heading {
  max-width: 700px;
  margin-bottom: var(--space-2xl);
}

.section-text {
  margin: 0;
  color: var(--color-text-muted);
  max-width: var(--reading-width);
  font-size: var(--font-size-large);
}

.stack-layout {
  display: grid;
  gap: var(--space-3xl);
}

.content-block + .content-block {
  padding-top: var(--space-xs);
}

.eyebrow {
  display: inline-block;
  margin: 0 0 var(--space-sm);
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-round);
  background: var(--color-accent-soft);
  color: var(--color-primary);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin-top: 0;
  color: var(--color-heading);
  line-height: var(--line-height-heading);
}

h1 {
  margin-bottom: 1.25rem;
  font-size: var(--font-size-h1);
  letter-spacing: -0.03em;
}

h2 {
  margin-bottom: 1rem;
  font-size: var(--font-size-h2);
  letter-spacing: -0.02em;
}

h3 {
  margin-bottom: var(--space-sm);
  font-size: var(--font-size-h3);
  letter-spacing: -0.01em;
}

p {
  margin-top: 0;
  margin-bottom: 0;
  max-width: var(--reading-width);
}

ul,
fieldset {
  margin: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: color-mix(in srgb, var(--color-background) 92%, transparent);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(10px);
}

.navbar {
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  padding: 0.75rem 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  min-width: 0;
}

.brand-mark {
  width: 2.5rem;
  height: 2.5rem;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  background: var(--color-primary);
  color: #ffffff;
  font-weight: 700;
}

.brand-text {
  color: var(--color-heading);
  font-weight: 700;
  line-height: 1.3;
}

.nav-shell {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.nav-toggle,
.search-input,
.filter-button,
.button-secondary {
  background: var(--color-background);
}

.nav-toggle {
  display: none;
  width: 2.85rem;
  height: 2.85rem;
  padding: var(--space-xs);
  border: 1px solid transparent;
  border-radius: var(--radius-round);
  cursor: pointer;
  transition: background-color var(--transition-base), border-color var(--transition-base);
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  background: var(--color-surface);
  border-color: var(--color-border);
}

.nav-toggle span {
  display: block;
  width: 1.5rem;
  height: 2px;
  margin: 0.28rem auto;
  border-radius: var(--radius-round);
  background: var(--color-heading);
}

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

.nav-list,
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm) var(--space-md);
  padding: 0;
  list-style: none;
}

.nav-list {
  align-items: center;
  gap: var(--space-xs);
}

.nav-menu a {
  display: inline-flex;
  padding: 0.8rem 1rem;
  border-radius: var(--radius-round);
  color: var(--color-text-muted);
  font-weight: 500;
  transition: background-color var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.nav-menu a:hover,
.nav-menu a:focus-visible,
.nav-menu a.is-active {
  background: var(--color-accent-soft);
  color: var(--color-primary);
  transform: translateY(-1px);
}

.hero {
  padding-top: calc(clamp(4rem, 8vw, 6rem) + 1rem);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(280px, 0.9fr);
  gap: var(--space-xl);
  align-items: center;
}

.hero h1 {
  font-size: var(--font-size-hero);
}

.hero-content .section-text {
  margin-top: var(--space-md);
}

.page-hero {
  background: linear-gradient(180deg, var(--color-background) 0%, var(--color-surface-muted) 100%);
}

.feature-panel {
  background: linear-gradient(180deg, var(--color-background) 0%, color-mix(in srgb, var(--color-accent-soft) 65%, var(--color-background)) 100%);
}

.hero-panel {
  padding: var(--space-2xl);
}

.panel-label {
  margin-bottom: var(--space-sm);
  color: var(--color-primary);
  font-size: var(--font-size-small);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
}

.hero-points span {
  padding: 0.45rem 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-round);
  background: var(--color-background);
  color: var(--color-primary);
  font-size: 0.9rem;
  font-weight: 600;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-top: var(--space-xl);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3.1rem;
  padding: 0.9rem 1.35rem;
  border: 1px solid transparent;
  border-radius: var(--radius-round);
  font-weight: 600;
  line-height: 1.2;
  transition: transform var(--transition-base), background-color var(--transition-base), border-color var(--transition-base), box-shadow var(--transition-base), color var(--transition-base);
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button-primary {
  background: var(--color-primary);
  color: #ffffff;
  box-shadow: var(--shadow-soft);
}

.button-primary:hover,
.button-primary:focus-visible {
  background: var(--color-primary-dark);
  box-shadow: var(--shadow-hover);
}

.button-secondary {
  color: var(--color-primary);
  border-color: var(--color-border-strong);
  box-shadow: 0 2px 0 rgba(15, 39, 64, 0.02);
}

.button-secondary:hover,
.button-secondary:focus-visible {
  background: var(--color-surface);
  border-color: var(--color-primary);
}

.button-small {
  min-height: auto;
  padding: 0.75rem 1rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.card-grid-three {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.card {
  padding: var(--space-xl);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-background);
  box-shadow: var(--shadow-card);
  transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.card:hover,
.card:focus-within {
  transform: translateY(-3px);
  border-color: var(--color-border-strong);
  box-shadow: var(--shadow-hover);
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-md);
  margin-bottom: var(--space-sm);
}

.card .button {
  margin-top: var(--space-md);
}

.card-intro,
.simple-list,
.notice-box p,
.footer-copy,
.search-feedback {
  color: var(--color-text-muted);
}

.card p + .button,
.card p + .text-link,
.card ul + .button {
  margin-top: var(--space-lg);
}

.card-list {
  height: 100%;
}

.text-link {
  color: var(--color-primary);
  font-weight: 600;
  text-underline-offset: 0.18em;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-round);
  background: var(--color-surface-strong);
  color: var(--color-primary);
  font-size: 0.8rem;
  font-weight: 700;
  white-space: nowrap;
}

.status-badge-live {
  background: var(--color-accent-soft);
  color: #245840;
}

.simple-list {
  padding-left: 1.1rem;
}

.simple-list li + li {
  margin-top: var(--space-sm);
}

.purpose-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-xl);
}

.purpose-item {
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.purpose-item p {
  max-width: 34rem;
  color: var(--color-text-muted);
}

.notice-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: var(--space-2xl);
}

.notice-box {
  padding: 1rem 1.15rem;
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: 0 4px 14px rgba(15, 39, 64, 0.03);
}

.notice-box strong {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--color-heading);
}

.notice-box-update {
  border-left-color: #4d88c7;
  background: color-mix(in srgb, var(--color-surface) 78%, #e8f1fb 22%);
}

.notice-box-announce {
  border-left-color: var(--color-accent);
  background: color-mix(in srgb, var(--color-surface) 80%, #eef7f1 20%);
}

.notice-box-featured {
  border-left-color: var(--color-primary);
  background: linear-gradient(180deg, var(--color-surface) 0%, color-mix(in srgb, var(--color-accent-soft) 55%, var(--color-surface)) 100%);
}

.resource-toolbar {
  display: grid;
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

.search-box {
  display: grid;
  gap: 0.6rem;
}

.search-label {
  font-weight: 600;
  color: var(--color-heading);
}

.search-input-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.search-input {
  flex: 1 1 18rem;
  min-height: 3.1rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-round);
  color: var(--color-text);
}

.search-input::placeholder {
  color: var(--color-text-muted);
}

.filter-fieldset {
  display: grid;
  gap: 0.75rem;
  padding: 0;
  border: 0;
}

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.filter-button {
  padding: 0.7rem 1rem;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-round);
  color: var(--color-primary);
  font-weight: 600;
  cursor: pointer;
  transition: background-color var(--transition-base), border-color var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.filter-button:hover,
.filter-button:focus-visible,
.filter-button.is-active {
  background: var(--color-accent-soft);
  border-color: var(--color-primary);
  transform: translateY(-1px);
}

.search-feedback {
  margin-bottom: 1rem;
}

.coming-soon-card {
  border-style: dashed;
  background: linear-gradient(180deg, var(--color-background) 0%, var(--color-surface) 100%);
}

.coming-soon-pill {
  display: inline-flex;
  align-items: center;
  margin-bottom: 0.85rem;
  padding: 0.35rem 0.7rem;
  border-radius: var(--radius-round);
  background: var(--color-accent-soft);
  color: var(--color-primary);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.empty-state-card {
  text-align: left;
  justify-self: stretch;
}

.is-hidden {
  display: none;
}

.card-grid-span {
  grid-column: 1 / -1;
}

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

.footer-layout {
  display: grid;
  gap: var(--space-xl);
  align-items: start;
}

.footer-layout-minimal {
  grid-template-columns: 1fr;
  justify-items: center;
  text-align: center;
}

.footer-nav {
  width: 100%;
}

.footer-links {
  justify-content: center;
}

.footer-links a {
  color: var(--color-primary);
  font-weight: 500;
  padding: 0.2rem 0;
}

/*
  ============================================
  Lesson plan prompt generator
  Scoped styles for the AI Tools subpage
  ============================================
*/

.lesson-plan-app {
  display: grid;
  gap: 0.8rem;
  padding: clamp(0.9rem, 1.8vw, 1.15rem);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, #ffffff 0%, #fbfdff 100%);
  box-shadow: 0 8px 22px rgba(15, 39, 64, 0.045);
}

.lesson-plan-form {
  display: grid;
  gap: 0.7rem;
}

.lesson-plan-section {
  padding: 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.96);
}

.lesson-plan-section-title {
  margin-bottom: 0.55rem;
}

.lesson-plan-section-title h2,
.lesson-plan-output-header h2 {
  margin-bottom: 0;
  font-size: 0.98rem;
}

.lesson-plan-grid {
  display: grid;
  gap: 0.65rem;
}

.lesson-plan-grid-info {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.lesson-plan-grid-stack {
  grid-template-columns: 1fr;
}

.lesson-plan-field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 0.72rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: #ffffff;
}

.lesson-plan-field label {
  font-weight: 600;
  color: var(--color-heading);
  font-size: 0.96rem;
}

.lesson-plan-selector {
  background: linear-gradient(180deg, #ffffff 0%, #f8fbfd 100%);
}

.lesson-plan-quick-select {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin-bottom: 0.05rem;
}

.lesson-plan-chip {
  padding: 0.42rem 0.68rem;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-round);
  background: var(--color-surface);
  color: var(--color-primary);
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.2;
  cursor: pointer;
  transition: background-color var(--transition-base), border-color var(--transition-base), color var(--transition-base), transform var(--transition-base);
}

.lesson-plan-chip:hover,
.lesson-plan-chip:focus-visible {
  background: var(--color-accent-soft);
  border-color: var(--color-primary);
  transform: translateY(-1px);
}

.lesson-plan-chip.is-active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #ffffff;
}

.lesson-plan-app input,
.lesson-plan-app textarea {
  width: 100%;
  border: 1px solid var(--color-border-strong);
  border-radius: 0.85rem;
  padding: 0.72rem 0.85rem;
  color: var(--color-text);
  background: #ffffff;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.lesson-plan-app input::placeholder,
.lesson-plan-app textarea::placeholder {
  color: var(--color-text-muted);
}

.lesson-plan-app input:focus,
.lesson-plan-app textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-focus);
}

.lesson-plan-app input.is-invalid {
  border-color: #b44b4b;
  box-shadow: 0 0 0 4px rgba(180, 75, 75, 0.12);
}

.lesson-plan-status {
  min-height: 1.5rem;
  margin: 0;
  color: #a53f3f;
  font-weight: 600;
  font-size: 0.95rem;
}

.lesson-plan-status.is-success {
  color: #245840;
}

.lesson-plan-actions {
  margin-top: 0;
  margin-bottom: 0;
}

.lesson-plan-output {
  padding: 0.85rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.96);
}

.lesson-plan-output-header {
  margin-bottom: 0.55rem;
}

.lesson-plan-output-header p {
  margin: 0.2rem 0 0;
  color: var(--color-text-muted);
  max-width: none;
  font-size: 0.95rem;
  line-height: 1.55;
}

.lesson-plan-output textarea {
  min-height: 19rem;
  line-height: 1.6;
  resize: vertical;
}

.lesson-plan-page .section {
  padding: clamp(2.25rem, 5vw, 3.5rem) 0;
}

.lesson-plan-page .section-compact {
  padding-top: 0;
}

.lesson-plan-hero {
  padding-bottom: 1.1rem;
}

.lesson-plan-hero .eyebrow {
  margin-bottom: 0.55rem;
  padding: 0.38rem 0.72rem;
}

.lesson-plan-hero h1 {
  margin-bottom: 0.65rem;
  font-size: clamp(1.9rem, 3.6vw, 2.65rem);
}

.lesson-plan-hero .section-text {
  font-size: 1rem;
  line-height: 1.65;
}

.lesson-plan-actions {
  gap: 0.7rem;
}

.lesson-plan-actions .button {
  min-height: 2.85rem;
  padding: 0.8rem 1.15rem;
}

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .nav-toggle {
    display: inline-block;
  }

  .nav-menu {
    position: absolute;
    top: calc(100% + 0.6rem);
    left: 0;
    right: 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    padding: 0.8rem;
    border: 1px solid var(--color-border-strong);
    border-radius: var(--radius-lg);
    background: var(--color-background);
    box-shadow: var(--shadow-soft);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    pointer-events: none;
    transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
  }

  .nav-menu.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.15rem;
  }

  .nav-menu a {
    width: 100%;
    padding: 0.95rem 1rem;
  }

  .navbar {
    position: relative;
    min-height: auto;
  }

  .brand-text {
    font-size: 0.95rem;
  }

  .section-heading {
    margin-bottom: var(--space-xl);
  }

  .lesson-plan-grid-info {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 600px) {
  .section {
    padding: 3.5rem 0;
  }

  .container {
    width: min(100% - 1.25rem, var(--container-width));
  }

  .card,
  .feature-panel {
    padding: var(--space-lg);
  }

  .button-row,
  .search-input-group {
    flex-direction: column;
    align-items: stretch;
  }

  .nav-shell {
    gap: 0.55rem;
  }

  .brand {
    gap: 0.65rem;
  }

  .brand-mark {
    width: 2.25rem;
    height: 2.25rem;
  }

  .brand-text {
    font-size: 0.88rem;
  }

  .hero-points {
    gap: var(--space-xs);
  }

  .hero-points span,
  .status-badge {
    font-size: 0.78rem;
  }

  .card-top {
    flex-direction: column;
    align-items: flex-start;
  }

  .filter-group {
    gap: 0.55rem;
  }

  .lesson-plan-app {
    padding: 0.75rem;
  }

  .lesson-plan-section,
  .lesson-plan-output {
    padding: 0.72rem;
  }

  .lesson-plan-grid-info {
    grid-template-columns: 1fr;
  }

  .lesson-plan-chip {
    width: auto;
  }

  .lesson-plan-hero {
    padding-bottom: 0.8rem;
  }

  .lesson-plan-hero h1 {
    margin-bottom: 0.5rem;
  }

  .lesson-plan-actions .button {
    width: 100%;
  }
}

@media print {
  .lesson-plan-app,
  .lesson-plan-section,
  .lesson-plan-output,
  .lesson-plan-field {
    box-shadow: none;
    background: #ffffff;
  }

  .lesson-plan-actions,
  .lesson-plan-status {
    display: none;
  }
}