/* ==========================================================================
   KinderFile — style.css
   Single-file stylesheet. Mobile-first, no build tools required.
   ========================================================================== */

/* --- Variables ----------------------------------------------------------- */
:root {
  --color-primary: #1B2A4A;
  --color-accent: #E8734A;
  --color-secondary: #7FB069;
  --color-bg: #FAFAF7;
  --color-text: #2D2D2D;
  --color-text-light: #6B7280;
  --color-border: #E5E7EB;
  --color-primary-light: #2A3F6E;
  --color-accent-light: #F09070;
  --color-bg-alt: #F0F1EC;

  --font-heading: 'Nunito', sans-serif;
  --font-body: 'Source Sans 3', 'Source Sans Pro', sans-serif;

  --max-width: 1120px;
  --max-width-narrow: 720px;
}

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

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

body {
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

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

ul, ol {
  padding-left: 1.25em;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-primary);
  line-height: 1.25;
}

h1 { font-size: 2.25rem; font-weight: 800; }
h2 { font-size: 1.75rem; font-weight: 700; }
h3 { font-size: 1.25rem; font-weight: 700; }

/* --- Utilities ----------------------------------------------------------- */
.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;
}

/* --- Buttons ------------------------------------------------------------- */
.btn {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: background 0.2s, color 0.2s, border-color 0.2s;
  text-align: center;
  line-height: 1.4;
}

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

.btn--primary:hover,
.btn--primary:focus-visible {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
}

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

.btn--outline:hover,
.btn--outline:focus-visible {
  background: var(--color-primary);
  color: #fff;
}

.btn--large {
  font-size: 1.125rem;
  padding: 1rem 2rem;
}

/* --- Navigation ---------------------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #fff;
  border-bottom: 1px solid var(--color-border);
}

.nav__container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo img {
  height: 40px;
  width: auto;
}

.nav__toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
}

.nav__toggle-bar {
  display: block;
  width: 24px;
  height: 2.5px;
  background: var(--color-primary);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(1) {
  transform: translateY(7.5px) rotate(45deg);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7.5px) rotate(-45deg);
}

.nav__menu {
  display: none;
  flex-direction: column;
  gap: 1rem;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: #fff;
  padding: 1.5rem;
  border-bottom: 1px solid var(--color-border);
  text-align: center;
}

.nav__menu.is-open {
  display: flex;
}

.nav__link {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1rem;
  color: var(--color-primary);
  padding: 0.5rem 0;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

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

.nav__cta {
  min-height: 44px;
}

/* --- Hero ---------------------------------------------------------------- */
.hero {
  background: var(--color-primary);
  color: #fff;
  padding: 4rem 1.5rem;
  text-align: center;
}

.hero__container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.hero__headline {
  color: #fff;
  font-size: 2.25rem;
  margin-bottom: 1rem;
}

.hero__subheadline {
  font-size: 1.125rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.85);
  max-width: 640px;
  margin: 0 auto 2rem;
}

.hero .btn--primary {
  margin-bottom: 2.5rem;
}

.hero__icons {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  max-width: 480px;
  margin: 0 auto;
}

.hero__icon-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.hero__icon-item span {
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.7);
  font-weight: 600;
}

/* --- Problem ------------------------------------------------------------- */
.problem {
  padding: 4rem 1.5rem;
  background: var(--color-bg);
}

.problem__container {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.problem__headline {
  margin-bottom: 1.5rem;
  text-align: center;
}

.problem__body p {
  margin-bottom: 1rem;
  color: var(--color-text);
}

.problem__body p:last-child {
  margin-bottom: 0;
}

/* --- How It Works -------------------------------------------------------- */
.how-it-works {
  padding: 4rem 1.5rem;
  background: var(--color-bg-alt);
}

.how-it-works__container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.how-it-works__headline {
  text-align: center;
  margin-bottom: 2.5rem;
}

.steps {
  display: grid;
  gap: 2rem;
}

.step {
  text-align: center;
  padding: 2rem 1.5rem;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.step__number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #fff;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1rem;
  margin-bottom: 1rem;
}

.step__icon {
  display: block;
  margin: 0 auto 1rem;
}

.step h3 {
  margin-bottom: 0.5rem;
}

.step p {
  color: var(--color-text-light);
}

/* --- Document Types ------------------------------------------------------ */
.doc-types {
  padding: 4rem 1.5rem;
  background: var(--color-bg);
}

.doc-types__container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.doc-types__headline {
  text-align: center;
  margin-bottom: 2.5rem;
}

.doc-types__grid {
  display: grid;
  gap: 1.25rem;
}

.doc-type {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  background: #fff;
  border-radius: 10px;
  border: 1px solid var(--color-border);
}

.doc-type svg {
  flex-shrink: 0;
}

.doc-type h3 {
  font-size: 1rem;
  font-weight: 700;
}

/* --- Pilot Offer --------------------------------------------------------- */
.pilot {
  padding: 4rem 1.5rem;
  background: var(--color-bg-alt);
}

.pilot__container {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
  text-align: center;
}

.pilot__headline {
  margin-bottom: 1rem;
}

.pilot__body {
  margin-bottom: 1.5rem;
  color: var(--color-text);
}

.pilot__subheadline {
  margin-bottom: 1rem;
  font-size: 1.125rem;
}

.pilot__list {
  text-align: left;
  max-width: 500px;
  margin: 0 auto;
  list-style: none;
  padding: 0;
}

.pilot__list li {
  padding: 0.5rem 0;
  padding-left: 1.75rem;
  position: relative;
  color: var(--color-text);
}

.pilot__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-secondary);
}

/* --- Signup Form --------------------------------------------------------- */
.signup {
  padding: 4rem 1.5rem;
  background: var(--color-primary);
}

.signup__container {
  max-width: 540px;
  margin: 0 auto;
}

.signup__headline {
  color: #fff;
  text-align: center;
  margin-bottom: 2rem;
}

.signup__form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.form-group label {
  color: rgba(255, 255, 255, 0.9);
  font-weight: 600;
  font-size: 0.9375rem;
}

.form-group input,
.form-group textarea {
  padding: 0.75rem 1rem;
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.95);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-text);
  transition: border-color 0.2s;
  min-height: 44px;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-accent);
}

.form-group textarea {
  resize: vertical;
}

.signup__form .btn {
  margin-top: 0.5rem;
  width: 100%;
}

.signup__success {
  text-align: center;
  padding: 2rem;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 10px;
}

.signup__success p {
  color: #fff;
  font-size: 1.125rem;
  font-weight: 600;
}

/* --- Footer -------------------------------------------------------------- */
.footer {
  background: #fff;
  border-top: 1px solid var(--color-border);
  padding: 2.5rem 1.5rem 1.5rem;
}

.footer__container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer__top {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer__logo img {
  height: 32px;
  width: auto;
}

.footer__tagline {
  color: var(--color-text-light);
  font-size: 0.9375rem;
}

.footer__links {
  display: flex;
  gap: 1.5rem;
}

.footer__links a {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--color-primary);
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

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

.footer__bottom {
  border-top: 1px solid var(--color-border);
  padding-top: 1.5rem;
}

.footer__bottom p {
  color: var(--color-text-light);
  font-size: 0.875rem;
}

/* --- Blog Index ---------------------------------------------------------- */
.blog-index {
  padding: 4rem 1.5rem;
}

.blog-index__container {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.blog-index__headline {
  margin-bottom: 2.5rem;
}

.blog-index__list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.blog-index__empty {
  color: var(--color-text-light);
  font-size: 1.125rem;
}

.blog-card {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border);
}

.blog-card__title {
  margin-bottom: 0.375rem;
}

.blog-card__title a {
  color: var(--color-primary);
}

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

.blog-card__date {
  display: block;
  font-size: 0.875rem;
  color: var(--color-text-light);
  margin-bottom: 0.5rem;
}

.blog-card__excerpt {
  color: var(--color-text);
  margin-bottom: 0.5rem;
}

.blog-card__link {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.9375rem;
  color: var(--color-accent);
}

.blog-card__link:hover {
  color: var(--color-accent-light);
}

/* --- Blog Banner --------------------------------------------------------- */
.blog-banner {
  background: var(--color-bg-alt);
  padding: 3rem 1.5rem;
  text-align: center;
}

.blog-banner__container {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.blog-banner__text {
  font-size: 1.25rem;
  margin-bottom: 1.5rem;
  color: var(--color-text);
}

/* --- Blog Post ----------------------------------------------------------- */
.blog-post {
  padding: 3rem 1.5rem 4rem;
}

.blog-post__container {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.blog-post__header {
  margin-bottom: 2rem;
}

.blog-post__title {
  margin-bottom: 0.75rem;
}

.blog-post__meta {
  display: flex;
  gap: 1rem;
  color: var(--color-text-light);
  font-size: 0.9375rem;
}

.blog-post__reading-time::before {
  content: "·";
  margin-right: 1rem;
}

.blog-post__image {
  border-radius: 10px;
  margin-bottom: 2rem;
}

.blog-post__content {
  margin-bottom: 2rem;
}

.blog-post__content h2 {
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.blog-post__content h3 {
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.blog-post__content p {
  margin-bottom: 1rem;
}

.blog-post__content ul,
.blog-post__content ol {
  margin-bottom: 1rem;
}

.blog-post__content li {
  margin-bottom: 0.25rem;
}

.blog-post__content a {
  color: var(--color-accent);
  text-decoration: underline;
}

.blog-post__content blockquote {
  border-left: 4px solid var(--color-accent);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
  color: var(--color-text-light);
  font-style: italic;
}

.blog-post__footer {
  margin-bottom: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border);
}

.blog-post__author {
  font-weight: 600;
  color: var(--color-text-light);
  margin-bottom: 0.5rem;
}

.blog-post__tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.blog-post__tag {
  font-size: 0.8125rem;
  padding: 0.25rem 0.75rem;
  background: var(--color-bg-alt);
  border-radius: 20px;
  color: var(--color-text-light);
  font-weight: 600;
}

/* --- Blog CTA Box -------------------------------------------------------- */
.blog-cta {
  background: var(--color-bg-alt);
  border-radius: 12px;
  padding: 2rem;
  text-align: center;
  margin-bottom: 2rem;
  border: 1px solid var(--color-border);
}

.blog-cta__text {
  margin-bottom: 1.25rem;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-text);
}

/* --- Related Posts -------------------------------------------------------- */
.related-posts__headline {
  margin-bottom: 1rem;
}

.related-posts__list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.related-posts__item {
  display: block;
  padding: 1.25rem;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  transition: border-color 0.2s;
}

.related-posts__item:hover {
  border-color: var(--color-accent);
}

.related-posts__item h3 {
  font-size: 1rem;
  margin-bottom: 0.25rem;
}

.related-posts__item time {
  font-size: 0.8125rem;
  color: var(--color-text-light);
}

/* --- Login Page ---------------------------------------------------------- */
.login {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: calc(100vh - 200px);
  padding: 3rem 1.5rem;
}

.login__card {
  max-width: 440px;
  width: 100%;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 3rem 2rem;
  text-align: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

.login__logo {
  margin: 0 auto 1.5rem;
}

.login__headline {
  font-size: 1.375rem;
  margin-bottom: 1rem;
}

.login__text {
  color: var(--color-text-light);
  margin-bottom: 1.5rem;
}

.login__cta a {
  color: var(--color-accent);
  font-weight: 600;
}

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

/* ==========================================================================
   Responsive — Tablet (768px+)
   ========================================================================== */
@media (min-width: 768px) {
  h1 { font-size: 2.75rem; }
  h2 { font-size: 2rem; }

  .nav__toggle {
    display: none;
  }

  .nav__menu {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 1.25rem;
    position: static;
    padding: 0;
    border: none;
    background: none;
  }

  .hero {
    padding: 5rem 2rem;
  }

  .hero__headline {
    font-size: 2.75rem;
  }

  .hero__icons {
    grid-template-columns: repeat(6, 1fr);
    max-width: 640px;
  }

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

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

  .footer__top {
    flex-direction: row;
    align-items: flex-start;
    justify-content: space-between;
  }

  .related-posts__list {
    flex-direction: row;
  }

  .related-posts__item {
    flex: 1;
  }
}

/* ==========================================================================
   Responsive — Desktop (1024px+)
   ========================================================================== */
@media (min-width: 1024px) {
  h1 { font-size: 3rem; }

  .hero {
    padding: 6rem 2rem;
  }

  .hero__headline {
    font-size: 3rem;
  }

  .hero__subheadline {
    font-size: 1.25rem;
  }

  .problem,
  .how-it-works,
  .doc-types,
  .pilot,
  .signup {
    padding: 5rem 2rem;
  }

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