/* =============== VARIABLES =============== */
:root {
  /* Colors */
  --primary-color: #1a365d;
  --secondary-color: #3182ce;
  --accent-color: #4299e1;
  --text-color: #2d3748;
  --text-light: #4a5568;
  --text-lighter: #718096;
  --bg-color: #ffffff;
  --bg-secondary: #f7fafc;
  --bg-tertiary: #edf2f7;
  --border-color: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;

  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --header-height: 5rem;
  --border-radius: 0.5rem;
  --border-radius-lg: 1rem;

  /* Transitions */
  --transition: all 0.3s ease;
  --transition-fast: all 0.15s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

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

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

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

ul {
  list-style: none;
}

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

/* =============== UTILITIES =============== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-sm);
}

.section {
  padding: var(--space-3xl) 0;
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section__subtitle {
  display: inline-block;
  padding: var(--space-xs) var(--space-md);
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--border-radius);
  margin-bottom: var(--space-sm);
}

.section__title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  color: var(--text-color);
  margin-bottom: var(--space-sm);
  line-height: 1.2;
}

.section__description {
  font-size: var(--font-size-lg);
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.6;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-sm) var(--space-lg);
  font-size: var(--font-size-base);
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--border-radius);
  transition: var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
  min-height: 48px;
}

.button--primary {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  box-shadow: var(--shadow);
}

.button--primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.button--outline {
  border-color: var(--secondary-color);
  color: var(--secondary-color);
  background: transparent;
}

.button--outline:hover {
  background: var(--secondary-color);
  color: white;
}

/* =============== HEADER =============== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  transition: var(--transition);
}

.nav {
  height: 100%;
}

.nav__container {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo img {
  height: 64px;
  width: auto;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.nav__link {
  font-weight: 500;
  color: var(--text-color);
  transition: var(--transition);
  position: relative;
}

.nav__link:hover,
.nav__link.active-link {
  color: var(--secondary-color);
}

.nav__link.active-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--secondary-color);
  border-radius: 2px;
}

.nav__cta {
  margin-left: var(--space-lg);
}

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  cursor: pointer;
}

.nav__toggle span {
  width: 25px;
  height: 2px;
  background: var(--text-color);
  transition: var(--transition);
}

/* =============== HERO =============== */
.hero {
  padding-top: calc(var(--header-height) + var(--space-3xl));
  background: linear-gradient(135deg, var(--bg-color) 0%, var(--bg-secondary) 100%);
  overflow: hidden;
}

.hero__container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: center;
  min-height: 80vh;
}

.hero__title {
  font-size: var(--font-size-5xl);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: var(--space-md);
}

.hero__title-gradient {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: block;
}

.hero__description {
  font-size: var(--font-size-xl);
  color: var(--text-light);
  margin-bottom: var(--space-xl);
  line-height: 1.7;
}

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

.hero__image {
  position: relative;
}

.hero__image img {
  width: 100%;
  height: auto;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
}

/* =============== SERVICES =============== */
.services {
  background: var(--bg-color);
}

.services__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-xl);
}

.service__card {
  background: white;
  border-radius: var(--border-radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid var(--border-color);
}

.service__card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.service__image {
  margin-bottom: var(--space-md);
  border-radius: var(--border-radius);
  overflow: hidden;
  height: 200px;
}

.service__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.service__title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--text-color);
}

.service__description {
  color: var(--text-light);
  line-height: 1.6;
}

/* =============== PROCESS =============== */
.process {
  background: var(--bg-secondary);
}

.process__timeline {
  max-width: 800px;
  margin: 0 auto;
}

.process__step {
  display: flex;
  gap: var(--space-lg);
  margin-bottom: var(--space-2xl);
  position: relative;
}

.process__step:last-child {
  margin-bottom: 0;
}

.process__step::after {
  content: '';
  position: absolute;
  left: 32px;
  top: 64px;
  width: 2px;
  height: calc(100% - 64px);
  background: var(--border-color);
}

.process__step:last-child::after {
  display: none;
}

.process__number {
  flex-shrink: 0;
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xl);
  font-weight: 700;
}

.process__title {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--text-color);
}

.process__description {
  color: var(--text-light);
  line-height: 1.6;
}

/* =============== TECH STACK =============== */
.tech {
  background: var(--bg-color);
}

.tech__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-xl);
}

.tech__category {
  text-align: center;
}

.tech__category-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-md);
  color: var(--text-color);
}

.tech__items {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  justify-content: center;
}

.tech__item {
  padding: var(--space-xs) var(--space-md);
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-color);
  transition: var(--transition);
}

.tech__item:hover {
  background: var(--secondary-color);
  color: white;
  border-color: var(--secondary-color);
}



/* =============== ABOUT =============== */
.about {
  background: var(--bg-color);
}

.about__container {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.about__description {
  font-size: var(--font-size-lg);
  color: var(--text-light);
  line-height: 1.7;
  margin-bottom: var(--space-lg);
}



/* =============== CONTACT =============== */
.contact {
  background: var(--bg-secondary);
}

.contact__container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: start;
}

.contact__info {
  display: grid;
  gap: var(--space-lg);
}

.contact__item-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: var(--space-xs);
}

.contact__item-value {
  color: var(--text-light);
  font-size: var(--font-size-base);
  line-height: 1.6;
  transition: var(--transition);
}

.contact__item-value:hover {
  color: var(--secondary-color);
}

.contact__cta {
  background: white;
  padding: var(--space-xl);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
  text-align: center;
}

.contact__cta-title {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--text-color);
}

.contact__cta-description {
  color: var(--text-light);
  line-height: 1.6;
  margin-bottom: var(--space-lg);
}

/* =============== FOOTER =============== */
.footer {
  background: var(--primary-color);
  color: white;
  padding: var(--space-2xl) 0;
}

.footer__container {
  display: grid;
  gap: var(--space-xl);
}

.footer__content {
  display: flex;
  justify-content: space-between;
  align-items: start;
}

.footer__brand {
  flex: 1;
}

.footer__logo {
  filter: brightness(0) invert(1);
  margin-bottom: var(--space-sm);
}

.footer__tagline {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
}

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

.footer__social-link {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  transition: var(--transition);
}

.footer__social-link:hover {
  color: white;
}

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer__copyright {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
}

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

.footer__link {
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  transition: var(--transition);
}

.footer__link:hover {
  color: white;
}

/* =============== BACK TO TOP =============== */
.back-to-top {
  position: fixed;
  bottom: var(--space-lg);
  right: var(--space-lg);
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  opacity: 0;
  visibility: hidden;
  z-index: 999;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* =============== RESPONSIVE DESIGN =============== */
@media screen and (max-width: 968px) {
  :root {
    --font-size-5xl: 2.5rem;
    --font-size-4xl: 2rem;
    --font-size-3xl: 1.75rem;
  }

  .nav__menu {
    position: fixed;
    top: var(--header-height);
    left: -100%;
    width: 100%;
    height: calc(100vh - var(--header-height));
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    transition: var(--transition);
    z-index: 999;
  }

  .nav__menu.show {
    left: 0;
  }

  .nav__list {
    flex-direction: column;
    padding: var(--space-xl);
    gap: var(--space-lg);
  }

  .nav__cta {
    margin: var(--space-lg) 0 0 0;
  }

  .nav__toggle {
    display: flex;
  }

  .hero__container {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
    text-align: center;
  }

  .contact__container {
    grid-template-columns: 1fr;
  }



  .footer__content {
    flex-direction: column;
    gap: var(--space-lg);
    text-align: center;
  }

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-md);
    text-align: center;
  }
}

@media screen and (max-width: 768px) {
  .container {
    padding: 0 var(--space-md);
  }

  .section {
    padding: var(--space-2xl) 0;
  }

  .hero__buttons {
    flex-direction: column;
    align-items: center;
  }

  .button {
    width: 100%;
    max-width: 280px;
  }

  .services__grid {
    grid-template-columns: 1fr;
  }

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

  .process__step::after {
    display: none;
  }

  .tech__grid {
    grid-template-columns: 1fr;
  }
}

@media screen and (max-width: 480px) {
  :root {
    --font-size-5xl: 2rem;
    --font-size-4xl: 1.75rem;
    --font-size-3xl: 1.5rem;
  }

  .container {
    padding: 0 var(--space-sm);
  }

  .hero__title {
    line-height: 1.2;
  }

  .process__number {
    width: 48px;
    height: 48px;
    font-size: var(--font-size-lg);
  }
}

/* =============== ACCESSIBILITY =============== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}

/* Focus styles */
*:focus-visible {
  outline: 2px solid var(--secondary-color);
  outline-offset: 2px;
}