/* =============================================================================
   style.css
   Main stylesheet for AdonaiApplications website template.
   Structure:
     1. CSS Custom Properties (Design Tokens)
     2. CSS Reset / Base
     3. Typography
     4. Layout Utilities
     5. Accessibility Utilities
     6. Components – Navigation
     7. Components – Buttons
     8. Sections – Hero
     9. Sections – Features
    10. Sections – About
    11. Sections – Contact / Form
    12. Footer
    13. Animations
    14. Media Queries
============================================================================= */

/* ---------------------------------------------------------------------------
   1. CSS Custom Properties (Design Tokens)
--------------------------------------------------------------------------- */
:root {
  /* Colours */
  --clr-primary:       #2563eb;   /* blue-600 */
  --clr-primary-dark:  #1d4ed8;   /* blue-700 */
  --clr-primary-light: #dbeafe;   /* blue-100 */
  --clr-accent:        #7c3aed;   /* violet-600 */
  --clr-text:          #1e293b;   /* slate-800 */
  --clr-text-muted:    #64748b;   /* slate-500 */
  --clr-bg:            #ffffff;
  --clr-bg-alt:        #f8fafc;   /* slate-50  */
  --clr-border:        #e2e8f0;   /* slate-200 */
  --clr-error:         #dc2626;   /* red-600   */
  --clr-success:       #16a34a;   /* green-600 */

  /* Typography */
  --font-sans:   'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono:   'Cascadia Code', 'Fira Code', monospace;

  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;

  --font-normal:  400;
  --font-medium:  500;
  --font-semibold: 600;
  --font-bold:    700;

  --leading-tight:  1.25;
  --leading-normal: 1.6;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --max-width:    1200px;
  --nav-height:   4rem;

  /* Borders & Shadows */
  --radius-sm:  0.25rem;
  --radius-md:  0.5rem;
  --radius-lg:  1rem;
  --radius-full: 9999px;

  --shadow-sm:  0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md:  0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg:  0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-normal: 250ms ease;
}

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

html {
  /* Smooth scrolling – respects prefers-reduced-motion via @media below */
  scroll-behavior: smooth;
  font-size: 100%; /* 16px base */
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--clr-text);
  background-color: var(--clr-bg);
  -webkit-font-smoothing: antialiased;
}

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

ul,
ol {
  list-style: none;
}

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

button {
  cursor: pointer;
  font-family: inherit;
  border: none;
  background: none;
}

input,
textarea {
  font-family: inherit;
  font-size: inherit;
}

/* Remove animations for users who prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ---------------------------------------------------------------------------
   3. Typography
--------------------------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--clr-text);
}

p {
  max-width: 65ch; /* optimal line length */
}

/* ---------------------------------------------------------------------------
   4. Layout Utilities
--------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.section__title {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-4);
}

.section__subtitle {
  font-size: var(--text-lg);
  color: var(--clr-text-muted);
  margin-bottom: var(--space-12);
  max-width: 55ch;
}

/* ---------------------------------------------------------------------------
   5. Accessibility Utilities
--------------------------------------------------------------------------- */

/* Skip navigation – visually hidden until focused (WCAG 2.4.1) */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  z-index: 9999;
  padding: var(--space-2) var(--space-4);
  background: var(--clr-primary);
  color: #fff;
  font-weight: var(--font-semibold);
  border-radius: var(--radius-md);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: var(--space-4);
}

/* Visible focus ring for keyboard users (WCAG 2.4.7) */
:focus-visible {
  outline: 3px solid var(--clr-primary);
  outline-offset: 3px;
}

/* Visually hidden but accessible to screen readers */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ---------------------------------------------------------------------------
   6. Components – Navigation
--------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--clr-bg);
  border-bottom: 1px solid var(--clr-border);
  box-shadow: var(--shadow-sm);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
}

.nav__logo {
  font-size: var(--text-xl);
  font-weight: var(--font-bold);
  color: var(--clr-primary);
  letter-spacing: -0.02em;
  transition: opacity var(--transition-fast);
}

.nav__logo:hover,
.nav__logo:focus-visible {
  opacity: 0.85;
}

/* Desktop menu */
.nav__menu {
  display: flex;
  gap: var(--space-8);
}

.nav__link {
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--clr-text);
  padding: var(--space-2) var(--space-1);
  border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.nav__link:hover,
.nav__link:focus-visible {
  color: var(--clr-primary);
  border-bottom-color: var(--clr-primary);
}

.nav__link[aria-current="page"] {
  color: var(--clr-primary);
  border-bottom-color: var(--clr-primary);
}

/* Hamburger toggle – hidden on desktop */
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 2.5rem;
  height: 2.5rem;
  padding: var(--space-2);
  border-radius: var(--radius-sm);
}

.nav__toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--clr-text);
  border-radius: var(--radius-full);
  transition: transform var(--transition-normal), opacity var(--transition-normal);
}

/* Open state – animated to an "X" */
.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;
  transform: scaleX(0);
}
.nav__toggle[aria-expanded="true"] .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------------------------------------------------------------------------
   7. Components – Buttons
--------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  text-decoration: none;
  transition:
    background-color var(--transition-fast),
    color var(--transition-fast),
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

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

.btn--primary:hover,
.btn--primary:focus-visible {
  background-color: var(--clr-primary-dark);
  border-color: var(--clr-primary-dark);
  box-shadow: var(--shadow-md);
}

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

.btn--secondary:hover,
.btn--secondary:focus-visible {
  background-color: var(--clr-primary-light);
  box-shadow: var(--shadow-sm);
}

/* ---------------------------------------------------------------------------
   8. Sections – Hero
--------------------------------------------------------------------------- */
.hero {
  min-height: calc(100dvh - var(--nav-height));
  display: flex;
  align-items: center;
  background: linear-gradient(
    135deg,
    var(--clr-primary-light) 0%,
    var(--clr-bg) 60%
  );
  padding-block: var(--space-20);
}

.hero__content {
  max-width: 640px;
}

.hero__title {
  font-size: clamp(var(--text-3xl), 5vw, var(--text-5xl));
  line-height: 1.1;
  margin-bottom: var(--space-6);
}

.hero__highlight {
  color: var(--clr-primary);
}

.hero__subtitle {
  font-size: var(--text-xl);
  color: var(--clr-text-muted);
  margin-bottom: var(--space-8);
  max-width: 50ch;
}

/* ---------------------------------------------------------------------------
   9. Sections – Features
--------------------------------------------------------------------------- */
.features {
  padding-block: var(--space-20);
  background-color: var(--clr-bg-alt);
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
}

.feature-card {
  background-color: var(--clr-bg);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-normal), transform var(--transition-normal);
}

.feature-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.feature-card__icon {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-4);
  line-height: 1;
}

.feature-card__title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-3);
}

.feature-card__desc {
  color: var(--clr-text-muted);
  font-size: var(--text-base);
}

/* ---------------------------------------------------------------------------
   10. Sections – About
--------------------------------------------------------------------------- */
.about {
  padding-block: var(--space-20);
}

.about__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-16);
  align-items: center;
}

.about__text .section__title {
  margin-bottom: var(--space-4);
}

.about__text p {
  color: var(--clr-text-muted);
  margin-bottom: var(--space-4);
}

.about__text .btn {
  margin-top: var(--space-4);
}

.about__image img {
  border-radius: var(--radius-lg);
  width: 100%;
  object-fit: cover;
  /* Placeholder gradient when the image is missing */
  background: linear-gradient(135deg, var(--clr-primary-light), var(--clr-border));
  min-height: 280px;
}

/* ---------------------------------------------------------------------------
   11. Sections – Contact / Form
--------------------------------------------------------------------------- */
.contact {
  padding-block: var(--space-20);
  background-color: var(--clr-bg-alt);
}

.contact__inner {
  max-width: 640px;
}

.contact__form {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  margin-top: var(--space-8);
}

.form__group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form__label {
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--clr-text);
}

.form__input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  background-color: var(--clr-bg);
  color: var(--clr-text);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form__input:focus {
  /* Transparent outline keeps high-contrast mode support while the visible
     focus ring is provided by the box-shadow below (WCAG 1.4.11). */
  outline: 2px solid transparent;
  border-color: var(--clr-primary);
  box-shadow: 0 0 0 3px rgb(37 99 235 / 0.2);
}

.form__input.is-invalid {
  border-color: var(--clr-error);
  box-shadow: 0 0 0 3px rgb(220 38 38 / 0.15);
}

.form__textarea {
  resize: vertical;
  min-height: 120px;
}

.form__error {
  font-size: var(--text-sm);
  color: var(--clr-error);
  min-height: 1.25em; /* prevent layout shift */
}

.form__success {
  padding: var(--space-3) var(--space-4);
  background-color: #dcfce7; /* green-100 */
  color: #15803d;             /* green-700 – 4.5:1 contrast on green-100 */
  border: 1px solid #86efac;  /* green-300 */
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
}

/* ---------------------------------------------------------------------------
   12. Footer
--------------------------------------------------------------------------- */
.site-footer {
  background-color: var(--clr-text);
  color: var(--clr-bg-alt);
  padding-block: var(--space-8);
}

.site-footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.site-footer__copy {
  font-size: var(--text-sm);
  color: #94a3b8; /* slate-400 – sufficient contrast on dark bg */
  max-width: none;
}

.site-footer__nav {
  display: flex;
  gap: var(--space-6);
}

.site-footer__nav a {
  font-size: var(--text-sm);
  color: #94a3b8;
  transition: color var(--transition-fast);
}

.site-footer__nav a:hover,
.site-footer__nav a:focus-visible {
  color: #fff;
}

/* ---------------------------------------------------------------------------
   13. Animations
--------------------------------------------------------------------------- */
@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-up {
  animation: fade-up 0.6s var(--transition-normal) both;
}

/* ---------------------------------------------------------------------------
   14. Media Queries
--------------------------------------------------------------------------- */

/* Tablet – up to 1024 px */
@media (max-width: 64em) {
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about__inner {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }

  .about__image {
    order: -1;
  }
}

/* Mobile – up to 768 px */
@media (max-width: 48em) {
  /* Show hamburger, hide desktop menu */
  .nav__toggle {
    display: flex;
  }

  .nav__menu {
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background-color: var(--clr-bg);
    border-bottom: 1px solid var(--clr-border);
    box-shadow: var(--shadow-md);
    /* Hidden by default */
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
  }

  .nav__menu.is-open {
    max-height: calc(100vh - var(--nav-height));
    overflow-y: auto;
  }

  .nav__link {
    display: block;
    padding: var(--space-4) var(--space-6);
    border-bottom: 1px solid var(--clr-border);
    font-size: var(--text-base);
  }

  /* Single-column features */
  .features__grid {
    grid-template-columns: 1fr;
  }

  .section__title {
    font-size: var(--text-2xl);
  }

  .site-footer__inner {
    flex-direction: column;
    text-align: center;
  }
}