:root {
  --primary: #1e3a8a;
  --secondary: #facc15;
  --light: #fbef76;
  --dark: #020617;
}

/* ===================== RESET ===================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}

body {
  background: var(--light);
  color: var(--dark);
  line-height: 1.6;
}

/* ===================== NAVBAR ===================== */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.2rem 5vw;
  background: var(--primary);
  color: #ffffff;
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  font-size: 1.6rem;
  font-weight: 700;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: #ffffff;
  font-size: 1rem;
  position: relative;
}

/* Smooth underline hover */
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.25rem;
  width: 0;
  height: 0.12rem;
  background: var(--secondary);
  transition: width 0.3s ease;
}

.nav-links a:hover::after {
  width: 100%;
}

.menu-toggle {
  display: none;
  font-size: 1.6rem;
  cursor: pointer;
  background: none;
  border: none;
  color: #ffffff;
}

/* ===================== MOBILE NAVBAR ===================== */
@media (max-width: 48em) {
  .menu-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--primary);

    flex-direction: column;
    align-items: center;
    gap: 1.5rem;

    padding: 1.8rem 0;

    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transform: translateY(-0.6rem);

    transition:
      max-height 0.4s ease,
      opacity 0.25s ease,
      transform 0.3s ease;
  }

  .nav-links.active {
    max-height: 40vh;
    opacity: 1;
    transform: translateY(0);
  }
}

/* ===================== PAGE CONTAINER ===================== */
.page-container {
  max-width: 90%;
  margin: 0 auto;
  padding: 2rem 0;
}

/* ===================== ARTICLE IMAGE ===================== */
.img-article {
  display: flex;
  justify-content: center;
}

.img-article img {
  width: 62vw;
  height: auto;
  max-height: 80vh;
  border-radius: 0.4rem;
  margin-bottom: 6vh;
}

/* ===================== HEADINGS ===================== */
h1 {
  text-align: center;
  font-size: 3rem;
  margin: 1vh 0 7vh;
  color: var(--primary);
}

h2 {
  background: #ffffff;
  padding: 2rem;
  margin-bottom: 3rem;
  border-radius: 1rem;
  font-size: 1.4rem;
  font-weight: normal;
}

/* ===================== CONTENT SECTIONS ===================== */
.book-section {
  display: flex;
  gap: 2rem;
  background: #ffffff;
  margin: 5vh auto 2rem;
  padding: 1.5rem;
  border-radius: 1rem;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.book-section:hover {
  transform: translateY(-0.25rem);
  box-shadow: 0 0.6rem 1.5rem rgba(0, 0, 0, 0.08);
}

.book-details {
  flex: 1;
}

.book-title {
  font-size: 1.85rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.book-description,
.book-reason {
  font-size: 1.1rem;
  margin-top: 1rem;
}

p {
  font-size: 1rem;
}

/* ===================== FOOTER ===================== */
.site-footer {
  background: var(--primary);
  color: var(--light);
}

.footer-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  gap: 3rem;
  padding: 4rem 6vw;
}

.footer-brand h3 {
  font-size: 1.6rem;
  margin-bottom: 1rem;
}

.footer-brand p {
  max-width: 36ch;
  color: #e5e7eb;
  line-height: 1.6;
}

.footer-links h4 {
  font-size: 1.1rem;
  margin-bottom: 1rem;
}

.footer-links ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.footer-links a {
  text-decoration: none;
  color: #e5e7eb;
  transition: color 0.3s ease;
}

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

.footer-bottom {
  text-align: center;
  padding: 1.4rem 6vw;
  border-top: 0.1rem solid rgba(255, 255, 255, 0.2);
}

.footer-bottom p {
  font-size: 0.95rem;
}

/* ===================== FOOTER RESPONSIVE ===================== */
@media (max-width: 48em) {
  .footer-container {
    grid-template-columns: 1fr;
    text-align: center;
    padding: 3rem 6vw;
    gap: 2.5rem;
  }

  .footer-brand p {
    max-width: 100%;
    margin: 0 auto;
  }
}

/* ===================== MOBILE CONTENT ===================== */
@media (max-width: 40em) {
  .page-container {
    max-width: 95%;
  }

  h1 {
    font-size: 2.1rem;
    margin-bottom: 4vh;
  }

  h2 {
    padding: 1.5rem;
    font-size: 1.25rem;
  }

  .img-article img {
    width: 100%;
    max-height: 50vh;
  }

  .book-section {
    flex-direction: column;
    gap: 1.5rem;
  }

  .book-title {
    font-size: 1.4rem;
  }

  .book-description,
  .book-reason {
    font-size: 1rem;
  }
}

/* ===================== ACCESSIBILITY ===================== */
a:focus-visible,
button:focus-visible {
  outline: 0.2rem solid var(--secondary);
  outline-offset: 0.2rem;
}