* {
    box-sizing: border-box;
}

:root {
    /* container-margin */
    --container-margin-lg: 250px;
    --container-margin-sm: 80px;

    /* section-vertical-padding */
    --section-padding-lg: 100px;
    --section-padding-sm: 40px;

    /* color-styles */
    --accent-1: #11637c;
    --accent-2: #001319;
    --neutral-1: #f5f9fa;
    --neutral-2: #e7eef0;
    --neutral-3: #d0d6d7;
    --neutral-4: #798082;
    --neutral-5: #282f2f;
    --neutral-1-opacity: rgba(245, 249, 250, 0.2);
}

html {
    font-size: 62.5%;
    scroll-behavior: smooth;
}

body {
    font-family: "PublicSans-VariableFont_wght", sans-serif;
    color: var(--neutral-5);
    background-color: var(--neutral-1);

    counter-reset: "nav";
}

/* text-styles-heading*/
.heading-1,
.heading-2,
.heading-3,
.heading-4,
.heading-5,
.heading-6,
.heading-7,
.heading-8 {
    font-family: "Thunder-VF", sans-serif;
    text-transform: uppercase;
    line-height: 1;
}

.heading-1 {
    font-size: min(28vw, 49rem);
    font-weight: 840;
    font-variation-settings: "CNTR" 61;
    text-transform: none;
}

.heading-2 {
    font-size: 10rem;
    font-weight: 800;
}

.heading-3 {
    font-size: 7.8rem;
    font-weight: 400;
}

.heading-4 {
    font-size: 6rem;
    font-weight: 800;
}

.heading-5 {
    font-size: 5.2rem;
    font-weight: 400;
}

.heading-6 {
    font-size: 4.8rem;
    font-weight: 700;
    line-height: 0.9;
}

.heading-7 {
    font-size: 4rem;
    font-weight: 400;
}

.heading-8 {
    font-size: 2.8rem;
    font-weight: 500;
}

/* text-styles-body*/

.body-1 {
    font-size: 3.2rem;
    font-weight: 500;
    line-height: 1;
}

.body-2 {
    font-size: 2rem;
    font-weight: 330;
    line-height: 1.2;
    text-transform: capitalize;
}

.body-3 {
    font-size: 1.5rem;
    font-weight: 480;
    line-height: 1.5;
}

.body-4 {
    font-size: 1.4rem;
    font-weight: 400;
    line-height: 1.5;
}

/* text-styles-label*/
.label-1,
.label-2 {
    text-transform: uppercase;
    font-weight: 500;
    line-height: 1;
    letter-spacing: 0.01em;
}

.label-1 {
    font-size: 1.4rem;
}

.label-2 {
    font-size: 1.2rem;
}

/* common */

strong {
    font-weight: 700;
}

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

.container-sm {
    max-width: calc(100% - var(--container-margin-sm));
    width: 1440px;
    margin-left: auto;
    margin-right: auto;
}

.container-lg {
    max-width: calc(100% - var(--container-margin-lg));
    width: 1440px;
    margin-left: auto;
    margin-right: auto;
}

.btn {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 50px;
    padding: 0 12px;
    border: 1px solid var(--accent-1);
    border-radius: 10px;
    color: var(--accent-1);
    font-family: "PublicSans-VariableFont_wght", sans-serif;
    font-size: 1.4rem;
    font-weight: 700;
    line-height: 1;
    letter-spacing: -0.03em;
    text-transform: uppercase;
    text-align: center;

    transition: background-color 0.3s, color 0.3s;
}

.btn:hover {
    background-color: var(--accent-1);
    color: var(--neutral-1);
}

.work-status {
    position: relative;
    display: flex;
    column-gap: 8px;
}

.work-status::before {
    content: "";
    display: inline-block;
    width: 10px;
    height: 10px;
    border-radius: 1000px;
    background-color: var(--accent-1);
}

.label {
    display: inline-flex;
    min-height: 24px;
    padding: 0 12px;
    justify-content: center;
    align-items: center;
    border-radius: 4px;
    background-color: var(--accent-1);
    color: var(--neutral-1);
}

.highlight-info__subtile {
    display: inline-block;
    color: var(--neutral-4);
    margin-bottom: 8px;
}

.highlight-info + .highlight-info {
    margin-top: 28px;
}

.highlight-info__desc {
    max-width: 400px;
}

/* header */

.header-subpage {
    border: 1px solid var(--neutral-3);
    position: sticky;
    top: 0px;
    background-color: var(--neutral-1);
    z-index: 1;
}

.header__inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.subpage-logo {
    margin-right: 100px;
}

.nav-bar__list {
    display: flex;
}

.nav-bar__link {
    padding: 16px;
}

.nav-bar__link:hover {
    text-decoration: underline;
    color: var(--accent-1);
}
/* sub-page-nav */

ol.nav-bar__list > .nav-bar__item {
    counter-increment: nav;
}

ol.nav-bar__list > .nav-bar__item::before {
    content: counter(nav, decimal-leading-zero) "-";
    font-size: 1.2rem;
    font-weight: 700;
    margin-right: -16px;
}

ol.nav-bar__list .nav-bar__link {
    padding-right: 28px;
}

ol.nav-bar__list .nav-bar__item:hover::before {
    color: var(--accent-1);
}

ol.nav-bar__list .nav-bar__item.active::before {
    color: var(--accent-1);
}

.nav-bar__item.active > .nav-bar__link {
    text-decoration: underline;
    color: var(--accent-1);
}

/* hero */

.hero {
    padding-top: var(--section-padding-sm);
}

.hero__inner {
    display: flex;
    flex-direction: column;
    gap: 36px;
}

.hero__content {
    margin-left: auto;
    max-width: 500px;
}

.hero__desc {
    margin: 16px 0px;
}

/* project list */

.project-list {
    padding-bottom: var(--section-padding-sm);
}

.project {
    display: flex;
    padding: 40px;
    gap: 24px;
    border-radius: 12px;
    background-color: var(--neutral-2);
}

.project + .project {
    margin-top: 80px;
}

.project-info,
.project-media {
    flex: 1;
}

.project-info__inner {
    position: sticky;
    top: 40px;
}

.project-info__heading {
    margin: 12px 0 28px;
}

.project-btn {
    display: inline-flex;
    margin-top: 40px;
}

.project-img {
    margin-bottom: 32px;
}

.project-thumb {
    width: 100%;
    object-fit: cover;
    border-radius: 4px;
    margin-bottom: 8px;
}

/* about */

.about {
    padding: var(--section-padding-lg) 0 var(--section-padding-lg);
}

.about-row {
    display: flex;
    justify-content: space-between;
}

.about-row + .about-row {
    margin-top: 80px;
}

.about-column {
    width: 34%;
}

.about-column__desc + .about-column__desc {
    margin-top: 28px;
}

.about-row-reverse {
    margin-top: 80px;
    display: flex;
    flex-direction: row-reverse;
}

.about-column__avatar {
    width: 100%;
    object-fit: cover;
    margin-left: auto;
}

/* break-section */

.break-section {
    padding: var(--section-padding-sm) 0 var(--section-padding-sm);
    overflow: hidden;
}

.break-section__inner {
    display: flex;
    column-gap: 44px;
}

.break-list {
    display: flex;
    column-gap: 44px;
    animation: marquee 16s linear infinite;
}

.break-item__heading {
    white-space: nowrap;
}

/* exploration */

.exploration {
    padding: var(--section-padding-lg) 0 var(--section-padding-lg);
}

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

.exploration-row + .exploration-row {
    margin-top: 80px;
}

.exploration-media {
    max-width: 760px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
}

.exploration-thumb {
    position: relative;
    overflow: hidden;
}

.exploration-thumb::after {
    content: "";
    position: absolute;
    inset: 0;
    background-color: var(--accent-2);
    opacity: 0;
    border-radius: 4px;

    transition: opacity 0.5s;
}

.exploration-thumb:hover::after {
    opacity: 85%;
}

.exploration-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 4px;
}

.exploration-row:first-child .exploration-thumb:nth-of-type(6) {
    grid-row: span 2;
}

.exploration-thumb__tags {
    display: flex;
    gap: 8px;
    position: absolute;
    bottom: -40px;
    left: 20px;
    z-index: 1;

    transition: bottom 0.4s;
}

.exploration-tag {
    display: inline-flex;
    height: 24px;
    padding: 0 12px;
    justify-content: center;
    align-items: center;
    border-radius: 4px;
    color: var(--neutral-1);
    background: var(--neutral-1-opacity);
    backdrop-filter: blur(6px);
}

.exploration-thumb:hover .exploration-thumb__tags {
    bottom: 20px;
}

.exploration-thumb__link {
    z-index: 1;
    right: 20px;
    top: -40px;
    position: absolute;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 28px;
    height: 28px;
    border-radius: 8px;
    background: var(--neutral-1);

    transition: top 0.4s;
}

.exploration-thumb__icon {
    color: var(--accent-1);
}

.exploration-thumb:hover .exploration-thumb__link {
    top: 20px;
}

/* footer */

.footer {
    padding: 40px 0;
    background-color: var(--neutral-2);
}

.footer__top-row,
.footer__bottom-row {
    display: flex;
    flex-direction: column;
}

.footer__top-row {
    margin-bottom: 100px;
    align-items: flex-end;
}

.footer__bottom-row {
    align-items: start;
}

.footer__highlight-info {
    width: 24%;
}

.footer__bottom-row {
    row-gap: 24px;
}

.footer-link__desc {
    transition: text-decoration 0.1s, color 0.1s;
}

.footer-link:hover .footer-link__desc {
    text-decoration: underline;
    color: var(--accent-1);
}

.footer-link__heading {
    position: relative;
    color: var(--accent-1);
}

.footer-link__heading::after {
    content: "";
    position: absolute;
    bottom: 8px;
    width: 100%;
    left: 0;
    background-color: var(--accent-1);
    height: 2px;

    transition: width 0.5s;
}

.footer-link:hover > .footer-link__heading::after {
    width: 0%;
}

/* back to top button */

.top-btn {
    column-gap: 8px;
    position: fixed;
    right: 16px;
    bottom: 16px;
    transform: translateY(50px);
    opacity: 0;
    pointer-events: none;
    background-color: var(--neutral-1);

    transition: transform 0.3s ease-out, opacity 0.3s ease-out,
        background-color 0.3s, color 0.3s;
}

.top-btn--show {
    z-index: 2;
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

/* =====subpage====== */

/* subpage-hero */

.subpage-hero {
    padding: var(--section-padding-lg) 0 var(--section-padding-lg);
}

.subpage-hero__content {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.subpage-hero__heading {
    text-align: center;
    text-wrap: balance;
}

.subpage-hero__desc {
    max-width: 480px;
    text-align: center;
}

.subpage-hero__media {
    border-radius: 20px;
    overflow: hidden;
    margin-top: 70px;
}

.subpage-hero__thumb {
    width: 100%;
    height: auto;
}

/* workoverview */
.workoverview {
    padding: var(--section-padding-sm) 0 var(--section-padding-sm);
}

.workoverview-inner {
    display: flex;
    justify-content: space-between;
    gap: 64px;
}

.workoverview__left-column,
.workoverview__right-column {
    flex: 1;
}

.workoverview__left-column {
    max-width: 650px;
}

.workoverview__right-column {
    max-width: 400px;
    padding-top: 32px;
}

.workoverview-heading {
    margin: 12px 0px 24px;
}

.workoverview-desc + .workoverview-desc {
    margin-top: 12px;
}

.workoverview-btn {
    margin: 24px 0 12px;
    max-width: 300px;
}

.workoverview-links {
    display: flex;
    column-gap: 4px;
}

.workoverview-img {
    display: flex;
    column-gap: 12px;
}

.workoverview-highlight {
    padding: 12px 0;
    border-top: 1px solid var(--neutral-3);
}

/*transition-section */

.transition-section {
    padding: var(--section-padding-lg) 0 var(--section-padding-sm);
}

.transition-section__inner {
    padding: var(--section-padding-lg) 0;
    color: var(--neutral-1);
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: var(--accent-1);
}

/* step-list */
.step-list {
    padding: var(--section-padding-lg) 0 var(--section-padding-lg);
}

.step + .step {
    border-top: 1px solid var(--neutral-3);
}

.step {
    display: flex;
    flex-direction: column;
    gap: 48px;
    padding: 64px 0;

    scroll-margin-top: 110px;
}

.step:first-child {
    padding-top: 0px;
}

.step:last-child {
    padding-bottom: 0px;
}

.step-row {
    display: flex;
    gap: 48px;
}

/* step-block */

.step-block {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0 80px;
    max-width: 500px;
    min-height: 200px;
    border-radius: 12px;
    background-color: var(--accent-1);
}

.step-block__inner {
    display: flex;
    justify-content: center;
    align-items: baseline;
    gap: 6px;
}

.step-block__desc-wrapper {
    padding-left: 6px;
    border-left: 1px solid var(--neutral-2);
}

.step-block__heading,
.step-block__desc {
    color: var(--neutral-2);
}

/* step-content */

.step-content,
.step-learning {
    flex: 1;
    border-radius: 12px;
    background: var(--neutral-2);
    padding: 64px;

    display: flex;
    flex-direction: column;
    gap: 44px;
}

.step-content--row {
    flex-direction: row;
    align-items: center;
}

.step-content__info {
    flex: 1;
    max-width: 620px;
}

.step-content__labels {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.step-content__heading,
.step-learning__heading {
    margin-bottom: 8px;
}

.step-content__media {
    flex: 1;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 44px;
}

.step-content__media-no-padding {
    margin: 0 -64px -64px;
}

.step-content__img--2columns {
    grid-column: span 2;
}

.step-content__thumb,
.step-content__video {
    width: 100%;
    object-fit: cover;
    border-radius: 20px;
    border: 1px solid var(--accent-1);
}

.step-content__thumb--no-border {
    border: none;
}

.step-content__header {
    display: flex;
    align-items: center;
    gap: 64px;
}

.step-content__video {
    flex: 1;
    min-width: 360px;
    cursor: pointer;
}

.step-content__media-label {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: start;
    gap: 8px;
}

/* step-learning */

.step-learning {
    flex-direction: row;
    gap: 32px;
    justify-content: space-between;
}

.step-learning__info {
    flex: 1;
    max-width: 420px;
}

.step-learning__desc-wrapper {
    flex: 1;
    max-width: 610px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

/* highlight-list */

.highlight-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 44px;
}

.highlight-item__heading {
    margin: 20px 0 4px;
}

/* step-showcase */

.step-showcase {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 36px;
}

.step-showcase--2columns {
    grid-column: span 2;
}
/* animation */

@keyframes marquee {
    from {
        transform: translateX(0%);
    }

    to {
        transform: translateX(-206%);
    }
}