html {
  box-sizing: border-box;
}

*,
*::before,
*::after {
  box-sizing: inherit;
}

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

img {
  max-width: 100%;
}

@font-face {
  font-family: "Montserrat";
  src: local("Montserrat-Regular"),
    url(../fonts/Montserrat-Regular.woff2) format("woff2"),
    url(../fonts/Montserrat-Regular.woff) format("woff");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Montserrat";
  src: local("Montserrat-SemiBold"),
    url(../fonts/Montserrat-SemiBold.woff2) format("woff2"),
    url(../fonts/Montserrat-SemiBold.woff) format("woff");
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Montserrat";
  src: local("Montserrat-Bold"),
    url(../fonts/Montserrat-Bold.woff2) format("woff2"),
    url(../fonts/Montserrat-Bold.woff) format("woff");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Montserrat";
  src: local("Montserrat-ExtraBold"),
    url(../fonts/Montserrat-ExtraBold.woff2) format("woff2"),
    url(../fonts/Montserrat-ExtraBold.woff) format("woff");
  font-weight: 800;
  font-style: normal;
  font-display: swap;
}

body {
  background-color: var(--color-bg);
  font-family: Montserrat, sans-serif;
  font-weight: 400;
}

:root {
  --color-bg: #fff;
  --gap: 20px;
  --columns: 4;
}

/* global */

.list-reset {
  margin: 0;
  padding: 0;
  list-style: none;
}

.flex {
  display: flex;
}

.container {
  max-width: 1660px;
  padding: 0 30px;
  margin: 0 auto;
  width: 100%;
}

.blur {
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(15px);
  background: rgba(255, 255, 255, 0.05); /* Очень легкая дымка */
}

.btn {
  padding: 20px 38px;
  border: none;
  border-radius: 16px;
  background-color: #fff;
  cursor: pointer;
  font-weight: 700;
  font-size: 16px;
  line-height: normal;
  color: #355d77;
}

.section-title {
  margin: 0;
  margin-bottom: 20px;
  font-size: 48px;
  font-weight: 600;
  color: #1e3a52;
}

.item-title {
  margin: 0;
  margin-bottom: 12px;
  font-weight: 600;
  color: #1e3a52;
}

.descr {
  margin: 0;
  font-size: 16px;
  line-height: 1.6;
  color: #4a5568;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  border: 0;
  padding: 0;
  white-space: nowrap;
  clip-path: inset(100%);
  clip: rect(0 0 0 0);
  overflow: hidden;
}

/* header */

.header {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000; /* Чтобы быть поверх hero */
  padding: 1rem 0;
  padding: 30px 0;
}

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

.nav__list {
  align-items: center;
  justify-content: center;
  gap: 96px;
  color: #fff;
  font-size: 24px;
}

.nav__link {
  position: relative;
  outline: none;
  font-size: 18px;
  transition: color 0.3s ease-in-out;
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -5px;
  height: 2px;
  width: 100%;
  background-color: #fff;
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.3s ease-in-out, background-color 0.3s ease-in-out;
}

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

.nav__link:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 4px;
}

.nav__link:active::after {
  height: 3px;
  background-color: #0b3c5d;
}

.nav__link:active {
  color: #0b3c5d;
  font-weight: 600;
}

.header__logo {
  align-items: center;
}

.burger {
  display: none;
}

.header__logo-img {
  width: 200px;
  height: auto;
}

.header__container::after {
  content: "";
  width: 200px;
}

/* hero */

.hero {
  padding: 150px 0;
  margin-bottom: 50px;
  background-image: url(../img/bg5.jpg);
  background-position: center;
  background-size: cover;
  background-repeat: no-repeat;
}

.hero__title {
  margin: 0;
  padding: 0;
  font-size: 90px;
  color: #fff;
  font-weight: 600;
}

.hero__descr {
  margin-bottom: 90px;
  font-size: 22px;
  color: #fff;
  font-weight: 400;
}

.hero__btn {
  position: relative;
  transition: background-color 0.3s ease-in-out, color 0.3s ease-in-out,
    transform 0.3s ease-in-out, box-shadow 0.3s ease-in-out;
  outline: none;
}

.hero__btn:hover {
  background-color: #355d77;
  color: #fff;
  transform: translateY(-3px);
  box-shadow: 0 10px 25px rgba(53, 93, 119, 0.3);
}

.hero__btn:focus {
  outline: none;
}

.hero__btn:focus-visible {
  box-shadow: 0 0 0 3px #fff, 0 0 0 6px #355d77;
}

.hero__btn:active {
  transform: translateY(-1px);
  box-shadow: 0 5px 15px rgba(53, 93, 119, 0.4);
  background-color: #2a4a5f;
}

/* about */

.about {
  margin-bottom: 50px;
  scroll-margin-top: 105px;
}

.about__descr {
  max-width: 66%;
}

/* approach */

.approach {
  margin-bottom: 25px;
  scroll-margin-top: 105px;
}

.approach__list {
  flex-wrap: wrap;
  gap: var(--gap);
}

.approach__item {
  flex: 0 0 calc((100% - (var(--columns) - 1) * var(--gap)) / var(--columns));
  flex-direction: column;
}

.approach__icon {
  height: 100px;
  width: auto;
  max-width: 100%;
  fill: #355d77;
  stroke: #355d77;
}

.approach__icon-wrap {
  margin-bottom: 24px;
}

/* program */

.program {
  padding: 25px 0;
  scroll-margin-top: 105px;
  background: #fafafa;
}

.program__descr {
  margin-bottom: 40px;
  font-size: 18px;
  max-width: 66%;
}

.program__list {
  margin-bottom: 40px;
  flex-direction: column;
  gap: 16px;
  max-width: 66%;
}

.program__item {
  padding: 20px 24px;
  background: white;
  border-radius: 8px;
  color: #4a5568;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  border-left: 3px solid #355d77;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.program__btns {
  gap: 16px;
}

.program__item:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.program__item strong {
  color: #2d3748;
  font-weight: 600;
}

.program__btn {
  display: inline-block;
  background-color: #355d77;
  color: #fff;
}

.program__btn:hover {
  background-color: #2a4a5f;
}

/* footer */

.footer__container {
  justify-content: space-between;
  align-items: center;
}

.footer__top {
  padding: 25px 0;
  border-top: 1px solid #e0e0e0;
}

.footer__form {
  flex-direction: column;
}

.form__row {
  align-items: center;
  gap: 20px;
}

.form__title {
  margin: 0;
  margin-bottom: 20px;
  font-size: 48px;
}

.form__input {
  padding: 12px 30px;
  border: 1px solid #ccc;
  border-radius: 100px;
  font-size: 16px;
  background-color: #fff;
  color: #333;
  transition: border-color 0.3s ease-in-out, box-shadow 0.3s ease-in-out,
    transform 0.2s ease-in-out;
  outline: none;
}

.form__input:hover {
  border-color: #355d77;
}

.form__input:focus {
  border-color: #355d77;
  box-shadow: 0 0 0 3px rgba(53, 93, 119, 0.1);
  transform: translateY(-1px);
}

.form__input:valid {
  border-color: #28a745;
}

.form__input:invalid:not(:placeholder-shown) {
  border-color: #dc3545;
}

.form__input::placeholder {
  color: #999;
  transition: color 0.3s ease-in-out;
}

.form__input:focus::placeholder {
  color: #ccc;
}

.form__btn {
  padding: 12px 35px;
  border: 1px solid #333;
  border-radius: 100px;
  background-color: #355d77;
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease-in-out;
  outline: none;
}

.form__btn:hover {
  background-color: #2a4a5f;
  border-color: #2a4a5f;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(53, 93, 119, 0.3);
}

.form__btn:focus {
  box-shadow: 0 0 0 3px rgba(53, 93, 119, 0.3);
}

.form__btn:active {
  transform: translateY(0);
  box-shadow: 0 2px 8px rgba(53, 93, 119, 0.4);
}

.form__btn:disabled {
  background-color: #ccc;
  border-color: #ccc;
  color: #666;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.footer__title {
  margin: 0;
  margin-bottom: 12px;
  font-size: 24px;
  font-weight: 400;
}

.footer__massengers {
  flex-direction: column;
}

.massengers {
  justify-content: flex-end;
  gap: 10px;
}

.massengers__link-icon {
  width: 50px;
  height: 50px;
  fill: #000;
  stroke: #000;
  transition: all 0.3s ease-in-out;
}

.massengers__link:hover .massengers__link-icon {
  fill: #5dc1f2;
  stroke: #5dc1f2;
}

.footer__bottom {
  padding: 25px 0;
  background-color: #000;
}

.footer__logo-img {
  width: 200px;
  height: auto;
}

.social__link-icon {
  width: 50px;
  height: 50px;
  fill: #fff;
  stroke: #fff;
  transition: all 0.3s ease-in-out;
}

.social__link:hover .social__link-icon {
  fill: #5dc1f2;
  stroke: #5dc1f2;
}

.footer__bottom-container {
  align-items: center;
  justify-content: space-between;
}

.social {
  gap: 10px;
}

.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  z-index: 1000;
  background-color: rgba(0, 0, 0, 0.5);
  align-items: center;
  justify-content: center;
  overflow-y: auto;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.3s ease-in-out;
}

.modal__content {
  position: relative;
  flex-direction: column;
  background-color: #fff;
  padding: 40px 30px;
  max-width: 500px;
  z-index: 1001;
  transform: scale(0);
  transition: transform 0.3s ease-in-out;
}

.form__fieldset {
  padding: 0;
  margin: 0;
  flex-direction: column;
  gap: 20px;
  border: none;
}

.modal--active {
  visibility: visible;
  opacity: 1;
}

.modal.modal--active .modal__content {
  transform: scale(1);
}

.modal__close {
  position: absolute;
  right: 8px;
  top: 8px;
  padding: 5px;
  border: none;
  background-color: transparent;
}

.modal__close-icon {
  width: 24px;
  height: 24px;
}