* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 500;
  line-height: 1.1;
}

h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }

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

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

ul {
  list-style: none;
}

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.container {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

/* Button component */
.btn {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 500;
  font-size: var(--fs-body);
  padding: 0.9rem 1.75rem;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  transition: border-color var(--transition), color var(--transition), background-color var(--transition);
}

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

.btn--accent:hover {
  background: var(--color-accent-hover);
  color: var(--color-bg);
}

/* Header / Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 10, 12, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-sm);
}

.logo {
  font-family: var(--font-heading);
  font-size: var(--fs-body-lg);
  font-weight: 500;
}

.nav__list {
  display: flex;
  gap: var(--space-md);
}

.nav__link {
  font-size: var(--fs-body);
  color: var(--color-text-muted);
  transition: color var(--transition);
}

.nav__link:hover,
.nav__link.is-active {
  color: var(--color-text);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-toggle__bar {
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) 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(-7px) rotate(-45deg);
}

@media (max-width: 767px) {
  .nav-toggle {
    display: flex;
  }

  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    max-height: 0;
    overflow: hidden;
    visibility: hidden;
    transition: max-height var(--transition), visibility var(--transition);
  }

  .nav.is-open {
    max-height: 300px;
    visibility: visible;
  }

  .nav__list {
    flex-direction: column;
    gap: 0;
    padding: var(--space-sm) var(--container-pad);
  }

  .nav__list li {
    padding-block: var(--space-xs);
  }
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-md);
  color: var(--color-text-muted);
  font-size: var(--fs-small);
}

.site-footer__links {
  display: flex;
  gap: var(--space-sm);
}

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

/* Scroll-reveal (populated behavior added in Task 7) */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 600ms ease, transform 600ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@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;
  }
}