:root {
  --color-dark-primary: #111827;
  --color-dark-secondary: #1F2937;
  --color-accent: #0ea5e9;
  --color-accent-hover: #38bdf8;
  --color-text-primary: #F9FAFB;
  --color-text-secondary: #9ca3af;
  --color-border: #374151;
  --font-family-base: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --container-width: 1240px;
  --container-padding: 1rem;
  --base-font-size: 16px;
  --transition-duration: 0.3s;
}

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

html {
  font-size: var(--base-font-size);
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  background-color: var(--color-dark-primary);
  color: var(--color-text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text-primary);
}

h1 { font-size: 3.5rem; }
h2 { font-size: 2.5rem; }
h3 { font-size: 1.75rem; }
p { font-size: 1rem; color: var(--color-text-secondary); margin-bottom: 1rem; }
a { color: var(--color-accent); text-decoration: none; transition: color var(--transition-duration) ease; }
a:hover { color: var(--color-accent-hover); }
img, svg { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
button { cursor: pointer; border: none; font-family: inherit; }

.container {
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.section {
  padding: 6rem 0;
  position: relative;
  overflow: hidden;
}

.section--secondary {
  background-color: var(--color-dark-secondary);
}

.section__title {
  text-align: center;
  margin-bottom: 1rem;
  font-size: 2.5rem;
}

.section__title--left {
  text-align: left;
}

.section__subtitle {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 4rem auto;
  color: var(--color-text-secondary);
}

.section__subtitle--left {
  text-align: left;
  margin: 0 0 2rem 0;
  max-width: 100%;
}

.button {
  display: inline-block;
  padding: 0.8rem 2rem;
  background-color: var(--color-accent);
  color: var(--color-text-primary);
  border-radius: 5px;
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.9rem;
  letter-spacing: 0.5px;
  transition: background-color var(--transition-duration) ease, transform var(--transition-duration) ease;
}

.button:hover {
  background-color: var(--color-accent-hover);
  transform: translateY(-3px);
  color: var(--color-text-primary);
}

.button--outline {
  background-color: transparent;
  border: 2px solid var(--color-accent);
  color: var(--color-accent);
}

.button--outline:hover {
  background-color: var(--color-accent);
  color: var(--color-text-primary);
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 1rem 0;
  z-index: 1000;
  background-color: rgba(17, 24, 39, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  transition: background-color var(--transition-duration) ease;
}

.header__container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header__logo-link {
  display: block;
}

.header__logo-img {
  height: 40px;
  width: auto;
}

.nav__list {
  display: flex;
  gap: 2.5rem;
}

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

.nav__link::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition-duration) ease;
}

.nav__link:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.header__actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.burger-menu {
  display: none;
  width: 30px;
  height: 22px;
  position: relative;
  cursor: pointer;
}

.burger-menu__line {
  display: block;
  width: 100%;
  height: 3px;
  background-color: var(--color-text-primary);
  position: absolute;
  left: 0;
  border-radius: 2px;
  transition: all var(--transition-duration) ease;
}

.burger-menu__line--top { top: 0; }
.burger-menu__line--middle { top: 50%; transform: translateY(-50%); }
.burger-menu__line--bottom { bottom: 0; }

.burger-menu.is-active .burger-menu__line--top { top: 50%; transform: translateY(-50%) rotate(45deg); }
.burger-menu.is-active .burger-menu__line--middle { opacity: 0; }
.burger-menu.is-active .burger-menu__line--bottom { bottom: 50%; transform: translateY(50%) rotate(-45deg); }

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding-top: 80px;
  background-repeat: no-repeat;
  background-position: center center;
  background-size: cover;
}
.hero--page { min-height: 60vh; }

.hero--home { background-image: url('images/0.webp'); }
.hero--about { background-image: url('images/10.webp'); }
.hero--services { background-image: url('images/13-1.webp'); }
.hero--service-hsr { background-image: url('images/15.webp'); }
.hero--service-urban { background-image: url('images/20.webp'); }
.hero--service-freight { background-image: url('images/26.webp'); }
.hero--configurator { background-image: url('images/32.webp'); }
.hero--legal { background-image: url('images/33.webp'); min-height: 40vh;}


.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--color-dark-primary) 30%, rgba(17, 24, 39, 0.6) 60%, rgba(17, 24, 39, 0.2) 100%);
  z-index: 1;
}

.hero__container {
  position: relative;
  z-index: 2;
}

.hero__content {
  max-width: 650px;
}

.hero__subtitle {
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--color-accent);
  margin-bottom: 1rem;
}

.hero__title {
  font-size: 4rem;
  margin-bottom: 1.5rem;
}

.hero__description {
  font-size: 1.1rem;
  margin-bottom: 2.5rem;
  max-width: 550px;
}

.hero__actions {
  display: flex;
  gap: 1rem;
}

.principles {
  padding: 6rem 0;
}

.principles__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2.5rem;
}

.principle-card {
  background-color: var(--color-dark-secondary);
  padding: 2.5rem;
  border-radius: 10px;
  border: 1px solid var(--color-border);
  text-align: center;
  transition: transform var(--transition-duration) ease, box-shadow var(--transition-duration) ease;
  display: flex;
  flex-direction: column;
}

.principle-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.principle-card__icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 1.5rem auto;
  color: var(--color-accent);
}

.principle-card__title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.principle-card__description {
  flex-grow: 1;
}

.principle-card__button {
  margin-top: 1.5rem;
}


.principle-card__avatar {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 1.5rem auto;
  border: 4px solid var(--color-border);
}

.principle-card__position {
  display: block;
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
}

.projects .swiper {
  width: 100%;
  padding-top: 50px;
  padding-bottom: 50px;
}

.projects .swiper-slide {
  background-position: center;
  background-size: cover;
  width: 400px;
  height: 500px;
  border-radius: 15px;
  overflow: hidden;
  position: relative;
}

.project-card--hsr350 { background-image: url(images/1.webp); }
.project-card--tram { background-image: url(images/2.webp); }
.project-card--freight { background-image: url(images/3.webp); }
.project-card--commuter { background-image: url(images/4.webp); }
.project-card--scenic { background-image: url(images/5.webp); }
.project-card--hydrogen { background-image: url(images/6.webp); }

.projects .swiper-slide-shadow-left,
.projects .swiper-slide-shadow-right {
  background-image: none;
}

.project-card__content {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 2rem;
  background: linear-gradient(to top, rgba(0,0,0,0.9) 0%, rgba(0,0,0,0) 100%);
  color: var(--color-text-primary);
  transform: translateY(50%);
  opacity: 0;
  transition: all 0.4s ease;
}

.projects .swiper-slide-active .project-card__content {
  transform: translateY(0);
  opacity: 1;
}

.project-card__title {
  font-size: 1.8rem;
  margin-bottom: 0.5rem;
}

.project-card__description {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

.project-card__stats {
  display: flex;
  gap: 1.5rem;
  margin-top: 1rem;
  border-top: 1px solid var(--color-border);
  padding-top: 1rem;
}

.project-card__stat {
  font-size: 0.8rem;
  font-weight: 600;
}

.technology {
  position: relative;
}

.technology__grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 3rem;
  align-items: center;
}
.technology__grid--reversed {
    grid-template-columns: 2fr 1fr;
}

.technology__text-content {
    padding-right: 2rem;
}

.technology__text-content--reversed {
    padding-left: 2rem;
    padding-right: 0;
}

.technology__image {
    width: 100%;
    border-radius: 10px;
    object-fit: cover;
    height: 100%;
}

.tabs__nav {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  position: sticky;
  top: 120px;
}

.tabs__button {
  width: 100%;
  padding: 1.5rem;
  background-color: var(--color-dark-secondary);
  color: var(--color-text-secondary);
  font-size: 1.1rem;
  font-weight: 600;
  text-align: left;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  transition: background-color var(--transition-duration) ease, color var(--transition-duration) ease;
}

.tabs__button:hover {
  background-color: var(--color-border);
  color: var(--color-text-primary);
}

.tabs__button.is-active {
  background-color: var(--color-accent);
  color: var(--color-text-primary);
  border-color: var(--color-accent);
}

.tabs__content-pane {
  display: none;
  background-color: var(--color-dark-secondary);
  border-radius: 8px;
  overflow: hidden;
}

.tabs__content-pane.is-active {
  display: block;
}

.tabs__pane-inner {
  padding: 2.5rem;
}

.tabs__pane-image {
  width: 100%;
  height: 300px;
  object-fit: cover;
}

.tabs__pane-title {
  font-size: 2rem;
  margin-bottom: 1rem;
}

.process {
  padding: 6rem 0;
}

.process__timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}

.process__timeline::after {
  content: '';
  position: absolute;
  width: 4px;
  background-color: var(--color-border);
  top: 0;
  bottom: 0;
  left: 50%;
  margin-left: -2px;
}

.process__item {
  padding: 1rem 3rem;
  position: relative;
  width: 50%;
}

.process__item--left {
  left: 0;
  text-align: right;
}

.process__item--right {
  left: 50%;
}

.process__item::after {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  right: -10px;
  background-color: var(--color-dark-primary);
  border: 4px solid var(--color-accent);
  top: 30px;
  border-radius: 50%;
  z-index: 1;
}

.process__item--right::after {
  left: -10px;
}

.process__item-content {
  padding: 2rem;
  background-color: var(--color-dark-secondary);
  border-radius: 8px;
  border: 1px solid var(--color-border);
}

.process__item-step {
  color: var(--color-accent);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.process__item-title {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.testimonials {
  padding: 6rem 0;
}

.testimonials .swiper {
  width: 100%;
  height: 100%;
}

.testimonials .swiper-slide {
  text-align: center;
  font-size: 18px;
  background: var(--color-dark-secondary);
  padding: 3rem;
  border-radius: 10px;
  border: 1px solid var(--color-border);
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
}

.testimonial-card__quote {
  font-size: 1.2rem;
  font-style: italic;
  margin-bottom: 1.5rem;
  max-width: 700px;
}

.testimonial-card__avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 1rem;
  border: 3px solid var(--color-accent);
}

.testimonial-card__author {
  font-weight: 700;
  font-size: 1.1rem;
}

.testimonial-card__title {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

.faq {
  padding: 6rem 0;
}

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

.accordion__item {
  background-color: var(--color-dark-secondary);
  margin-bottom: 1rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  overflow: hidden;
}

.accordion__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem;
  cursor: pointer;
  width: 100%;
  background: none;
  text-align: left;
}

.accordion__title {
  font-size: 1.2rem;
  color: var(--color-text-primary);
  font-weight: 600;
}

.accordion__icon {
  width: 24px;
  height: 24px;
  color: var(--color-text-secondary);
  transition: transform var(--transition-duration) ease;
  flex-shrink: 0;
  margin-left: 1rem;
}

.accordion__item.is-active .accordion__icon {
  transform: rotate(45deg);
  color: var(--color-accent);
}

.accordion__content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease-out;
}

.accordion__content-inner {
  padding: 0 1.5rem 1.5rem;
}

.contact {
  padding: 6rem 0;
  position: relative;
}

.contact::before {
  content: '';
  position: absolute;
  top: 0;
  left: -50%;
  width: 200%;
  height: 100%;
  background-color: var(--color-dark-secondary);
  transform: skewY(-3deg);
  z-index: -1;
}

.contact__info {
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

.contact__info-title {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.contact__info-text {
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

.contact__details {
    margin-top: 2rem;
}

.contact__details-item {
    font-size: 1.2rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.contact__details-item a {
    color: var(--color-text-primary);
}

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

.footer {
  padding: 4rem 0 2rem;
  background-color: var(--color-dark-primary);
  border-top: 1px solid var(--color-border);
}

.footer__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer__col-title {
  font-size: 1.2rem;
  margin-bottom: 1.5rem;
}

.footer__logo-img {
  height: 40px;
  margin-bottom: 1rem;
}

.footer__social-list {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
}

.footer__social-link svg {
  width: 24px;
  height: 24px;
  color: var(--color-text-secondary);
  transition: color var(--transition-duration) ease;
}

.footer__social-link:hover svg {
  color: var(--color-accent);
}

.footer__nav-list {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.footer__nav-link {
  color: var(--color-text-secondary);
}

.footer__nav-link:hover {
  color: var(--color-text-primary);
}

.footer__contact-item {
  color: var(--color-text-secondary);
  margin-bottom: 0.5rem;
}

.footer__bottom {
  border-top: 1px solid var(--color-border);
  padding-top: 2rem;
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

.global-map__image {
    border-radius: 10px;
    border: 1px solid var(--color-border);
}

.global-map__details {
    display: flex;
    justify-content: space-around;
    text-align: center;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.global-map__item {
    padding: 1rem;
}

.global-map__item-title {
    font-size: 1.5rem;
    color: var(--color-accent);
}

.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list__item {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
}

.feature-list__icon {
    width: 20px;
    height: 20px;
    color: var(--color-accent);
    margin-right: 0.5rem;
    flex-shrink: 0;
}

.spec-table {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    border-collapse: collapse;
    text-align: left;
}

.spec-table__row--header {
    border-bottom: 2px solid var(--color-accent);
}

.spec-table__cell {
    padding: 1rem;
}

.spec-table tbody tr {
    border-bottom: 1px solid var(--color-border);
}

.spec-table tbody tr:nth-child(even) {
    background-color: var(--color-dark-secondary);
}

.gallery-slider .swiper-slide {
    padding: 0;
    background: none;
    border: none;
    border-radius: 10px;
    overflow: hidden;
}

.gallery-slider__image {
    width: 100%;
    height: 370px;
    object-fit: cover;
}

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

.legal-page h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--color-accent);
}

.legal-page h3 {
    font-size: 1.5rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 0.5rem;
}

.legal-page p, .legal-page li {
    color: var(--color-text-secondary);
}

.legal-page ul {
    list-style: disc;
    padding-left: 2rem;
}

.legal-page strong {
    color: var(--color-text-primary);
    font-weight: 600;
}

.configurator {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 3rem;
}

.configurator__controls {
    background-color: var(--color-dark-secondary);
    padding: 2rem;
    border-radius: 10px;
    border: 1px solid var(--color-border);
}

.stepper {
    display: flex;
    justify-content: space-between;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--color-border);
}

.stepper__item {
    display: flex;
    flex-direction: column;
    align-items: center;
    color: var(--color-text-secondary);
}

.stepper__item.is-active .stepper__number {
    background-color: var(--color-accent);
    color: var(--color-text-primary);
    border-color: var(--color-accent);
}
.stepper__item.is-active .stepper__label {
    color: var(--color-text-primary);
}


.stepper__number {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    border: 2px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    margin-bottom: 0.5rem;
    transition: all var(--transition-duration) ease;
}

.stepper__label {
    font-size: 0.8rem;
}

.configurator__step {
    display: none;
}

.configurator__step.is-active {
    display: block;
}

.option-group__title {
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

.option-group__item {
    margin-bottom: 1rem;
}

.option-group__label {
    display: block;
    background-color: var(--color-dark-primary);
    padding: 1rem;
    border: 1px solid var(--color-border);
    border-radius: 5px;
    cursor: pointer;
    transition: all var(--transition-duration) ease;
}

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

.option-group__input {
    display: none;
}

.option-group__input:checked + .option-group__label {
    border-color: var(--color-accent);
    background-color: var(--color-accent-hover);
    color: var(--color-dark-primary);
}

.option-group--colors {
    display: flex;
    gap: 1rem;
}
.option-group__color-label {
  display: block;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid var(--color-border);
    transition: all var(--transition-duration) ease;
}
.option-group__color-label:hover {
    transform: scale(1.1);
}
.option-group__input:checked + .option-group__color-label {
    border-color: var(--color-text-primary);
    box-shadow: 0 0 0 3px var(--color-accent);
}

.configurator__nav {
    display: flex;
    justify-content: space-between;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--color-border);
}

.configurator__preview {
    position: sticky;
    top: 120px;
    height: 500px;
    background: linear-gradient(to top, #111827, #374151);
    border-radius: 10px;
    overflow: hidden;
}

.configurator__preview-svg {
    width: 100%;
    height: 100%;
}

.summary {
    list-style: none;
    padding: 0;
}

.summary__item {
    display: flex;
    justify-content: space-between;
    padding: 0.8rem 0;
    border-bottom: 1px dashed var(--color-border);
}
.summary__key {
    color: var(--color-text-secondary);
}
.summary__value {
    font-weight: bold;
    color: var(--color-accent);
}

@keyframes move-track {
    from { transform: translateX(0); }
    to { transform: translateX(-1000px); }
}

#track {
    animation: move-track 10s linear infinite;
}

@media (max-width: 992px) {
  h1 { font-size: 2.5rem; }
  .hero__title { font-size: 3rem; }
  .nav { display: none; }
  .header__actions .button { display: none; }
  .burger-menu { display: block; }
  .header__nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: var(--color-dark-secondary);
    padding: 2rem;
  }
  .header__nav.is-active {
    display: block;
  }
  .nav__list {
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
  }
  .process__timeline::after { left: 30px; }
  .process__item { width: 100%; padding-left: 70px; padding-right: 1rem; }
  .process__item--left, .process__item--right { left: 0; text-align: left; }
  .process__item::after { left: 20px; }
  .configurator { grid-template-columns: 1fr; }
  .configurator__preview { position: static; height: 300px; margin-top: 2rem; }
}

@media (max-width: 768px) {
  .section { padding: 4rem 0; }
  .hero { text-align: center; }
  .hero::before { background: linear-gradient(to top, var(--color-dark-primary) 10%, rgba(17, 24, 39, 0.7) 100%); }
  .hero__content { margin: 0 auto; }
  .hero__actions { justify-content: center; }
  .technology__grid, .technology__grid--reversed { grid-template-columns: 1fr; }
  .technology__text-content, .technology__text-content--reversed { padding: 0; }
  .technology__image-container { margin-top: 2rem; }
  .technology__grid--reversed .technology__image-container { grid-row: 1; }
  .tabs__nav { position: static; }
  .process__item-content, .configurator__controls
  {
    padding: 1rem;
  }
}

@media (max-width: 480px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.8rem; }
  .hero__title { font-size: 2.5rem; }
  .projects .swiper-slide { width: 300px; height: 400px; }
  .footer__grid { grid-template-columns: 1fr; text-align: center; }
  .footer__social-list { justify-content: center; }
  .principles__grid
  {
    grid-template-columns: 1fr;
  }
}

.fr1
{
  background-color: #0ea5e9;
}
.fr2
{
  background-color: #9ca3af;
}
.fr3
{
  background-color: #ef4444;
}
.fr4
{
  background-color: #22c55e;
}