@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Pretendard:wght@400;500;600;700&display=swap");

:root {
    --color-bg: #0b1120;
    --color-surface: #ffffff;
    --color-surface-alt: #101f37;
    --color-muted: #64748b;
    --color-muted-strong: #cbd5f5;
    --color-primary: #2563eb;
    --color-primary-soft: rgba(37, 99, 235, 0.12);
    --color-accent: #22d3ee;
    --color-border: rgba(148, 163, 184, 0.35);
    --shadow-soft: 0 18px 35px -22px rgba(15, 23, 42, 0.65);
    --shadow-strong: 0 32px 55px -30px rgba(15, 23, 42, 0.45);
    --font-sans: "Inter", "Pretendard", "Segoe UI", "Apple SD Gothic Neo", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    --max-width: 1200px;
    --radius: 16px;
    --transition: 200ms ease;
}

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

html {
    color-scheme: light dark;
}

body {
    margin: 0;
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.65;
    color: #e2e8f0;
    background: radial-gradient(circle at top left, rgba(37, 99, 235, 0.18), transparent 45%), radial-gradient(circle at bottom right, rgba(34, 211, 238, 0.14), transparent 50%), var(--color-bg);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition);
}

img {
    max-width: 100%;
    display: block;
    border-radius: calc(var(--radius) / 2);
}

.container {
    width: min(100%, var(--max-width));
    margin-inline: auto;
    padding: 0 clamp(1rem, 3vw, 2rem);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(11, 17, 32, 0.84);
    border-bottom: 1px solid rgba(148, 163, 184, 0.18);
}

.site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
    padding: 1rem 0.5rem;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    font-size: 1.05rem;
}

.brand__logo {
    width: 32px;
    height: auto;
    display: block;
    filter: drop-shadow(0 0 8px rgba(34, 211, 238, 0.35));
}

.brand__text {
    display: inline-block;
}

.nav-toggle {
    display: none;
    background: rgba(37, 99, 235, 0.15);
    color: #f8fafc;
    border: 1px solid rgba(37, 99, 235, 0.4);
    border-radius: 99px;
    padding: 0.55rem 0.9rem;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: background var(--transition), border var(--transition), transform var(--transition);
}

.nav-toggle:focus-visible {
    outline: 3px solid rgba(34, 211, 238, 0.6);
    outline-offset: 3px;
}

.primary-nav {
    display: flex;
    align-items: center;
    gap: 1.75rem;
}

.primary-nav__links {
    display: flex;
    align-items: center;
    gap: clamp(1rem, 2vw, 1.75rem);
    list-style: none;
    margin: 0;
    padding: 0;
}

.primary-nav__item {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0.45rem;
}

.primary-nav__trigger {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.35rem 0;
    border: 0;
    background: transparent;
    font: inherit;
    color: #e2e8f0;
    font-weight: 600;
    font-size: 0.95rem;
    letter-spacing: 0.01em;
    cursor: pointer;
    transition: color var(--transition);
}

.primary-nav__trigger::after {
    content: "";
    width: 0.5rem;
    height: 0.5rem;
    border-right: 2px solid currentColor;
    border-bottom: 2px solid currentColor;
    transform: rotate(45deg);
    transition: transform var(--transition);
    margin-top: -0.15rem;
}

.primary-nav__trigger:hover,
.primary-nav__trigger:focus-visible,
.primary-nav__trigger.is-active {
    color: #ffffff;
}

.primary-nav__trigger[aria-expanded="true"]::after {
    transform: rotate(-135deg);
    margin-top: 0.2rem;
}

.primary-nav__item:hover > .primary-nav__trigger,
.primary-nav__item:focus-within > .primary-nav__trigger {
    color: #ffffff;
}

.sub-nav {
    position: absolute;
    top: calc(100% + 0.75rem);
    left: 0;
    min-width: 220px;
    background: rgba(12, 19, 35, 0.95);
    border: 1px solid rgba(148, 163, 184, 0.18);
    border-radius: 16px;
    padding: 1.1rem;
    display: grid;
    gap: 0.6rem;
    box-shadow: var(--shadow-strong);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity var(--transition), transform var(--transition);
}

.primary-nav__item:hover > .sub-nav,
.primary-nav__item:focus-within > .sub-nav,
.primary-nav__item.is-open > .sub-nav {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}

.sub-nav__link {
    display: inline-flex;
    flex-direction: column;
    gap: 0.15rem;
    color: #cbd5f5;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.01em;
    transition: color var(--transition);
}

.sub-nav__link:hover,
.sub-nav__link:focus-visible,
.sub-nav__link.is-active {
    color: #ffffff;
}

.primary-nav__item.is-current > .primary-nav__trigger {
    color: #ffffff;
}

.primary-nav__item.is-current > .primary-nav__trigger::after {
    transform: rotate(-135deg);
    margin-top: 0.2rem;
}

.language-switch {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid rgba(148, 163, 184, 0.2);
    border-radius: 999px;
    padding: 0.25rem;
}

.language-switch button {
    appearance: none;
    border: none;
    border-radius: 999px;
    padding: 0.35rem 0.85rem;
    background: transparent;
    color: #cbd5f5;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    cursor: pointer;
    transition: background var(--transition), color var(--transition);
}

.language-switch button.is-active {
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.85), rgba(34, 211, 238, 0.6));
    color: #0f172a;
}

main {
    display: block;
}

.hero {
    position: relative;
    padding: clamp(6rem, 18vw, 9rem) 0 clamp(4rem, 12vw, 6rem);
}

.hero::after {
    content: "";
    position: absolute;
    inset: 10% 10% auto;
    height: clamp(220px, 30vw, 320px);
    background: linear-gradient(120deg, rgba(37, 99, 235, 0.12), rgba(34, 211, 238, 0.08));
    filter: blur(40px);
    z-index: -1;
}

.hero__eyebrow {
    font-size: 0.9rem;
    letter-spacing: 0.28em;
    text-transform: uppercase;
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: 1.25rem;
}

.hero__title {
    font-size: clamp(2.4rem, 6vw, 3.75rem);
    line-height: 1.08;
    font-weight: 700;
    color: #ffffff;
    max-width: 12ch;
    margin: 0 0 1.25rem;
}

.hero__lede {
    max-width: 56ch;
    color: var(--color-muted-strong);
    font-size: clamp(1.05rem, 2.5vw, 1.2rem);
    margin: 0 0 2.5rem;
}

.cta-group {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    padding: 0.75rem 1.6rem;
    font-weight: 600;
    font-size: 0.95rem;
    letter-spacing: 0.02em;
    border: 1px solid transparent;
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
    box-shadow: var(--shadow-soft);
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-primary), #3b82f6);
    color: #f8fafc;
}

.btn--ghost {
    background: rgba(15, 23, 42, 0.4);
    border-color: rgba(148, 163, 184, 0.35);
    color: #e2e8f0;
}

.btn:hover,
.btn:focus-visible {
    transform: translateY(-1px);
    box-shadow: var(--shadow-strong);
}

.is-hidden {
    display: none !important;
}

section {
    padding: clamp(4.5rem, 12vw, 6.5rem) 0;
}

.section-headline {
    margin-bottom: 2.5rem;
}

.section-eyebrow {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.24em;
    color: var(--color-accent);
    font-weight: 600;
    margin-bottom: 0.85rem;
}

.section-title {
    font-size: clamp(1.85rem, 4vw, 2.4rem);
    line-height: 1.2;
    color: #f8fafc;
    margin: 0 0 1rem;
}

.section-copy {
    color: var(--color-muted-strong);
    max-width: 68ch;
    margin: 0;
}

.feature-grid,
.card-grid,
.timeline {
    display: grid;
    gap: clamp(1.5rem, 4vw, 2.5rem);
}

.feature-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.feature-card,
.content-card {
    background: rgba(15, 23, 42, 0.65);
    border-radius: var(--radius);
    border: 1px solid rgba(148, 163, 184, 0.1);
    padding: clamp(1.5rem, 4vw, 2rem);
    box-shadow: var(--shadow-soft);
}

.feature-card h3,
.content-card h3,
.content-card h4 {
    margin-top: 0;
    margin-bottom: 0.85rem;
    color: #f8fafc;
}

.feature-card p,
.content-card p {
    color: var(--color-muted-strong);
    margin: 0;
}

.colored-swatch {
    width: 70px;
    height: 70px;
    border-radius: 18px;
    border: 1px solid rgba(148, 163, 184, 0.2);
    margin-bottom: 1rem;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.color-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.two-column {
    display: grid;
    gap: clamp(2rem, 5vw, 3.5rem);
}

@media (min-width: 900px) {
    .two-column {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

.timeline {
    position: relative;
    padding-left: 1.75rem;
}

.timeline::before {
    content: "";
    position: absolute;
    inset: 0 auto 0 0;
    width: 2px;
    background: linear-gradient(180deg, rgba(37, 99, 235, 0.22), rgba(34, 211, 238, 0.18));
}

.timeline__item {
    position: relative;
    padding-left: 1.5rem;
}

.timeline__item::before {
    content: "";
    position: absolute;
    left: -1.8rem;
    top: 0.2rem;
    width: 11px;
    height: 11px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    box-shadow: 0 0 12px rgba(34, 211, 238, 0.7);
}

.timeline__year {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    color: var(--color-accent);
    margin-bottom: 0.4rem;
}

.content-surface {
    background: rgba(10, 18, 35, 0.75);
    border: 1px solid rgba(148, 163, 184, 0.12);
    border-radius: var(--radius);
    padding: clamp(2.5rem, 7vw, 3.5rem);
    box-shadow: var(--shadow-soft);
}

.content-surface h2,
.content-surface h3 {
    color: #ffffff;
    margin-top: 0;
}

.content-surface p,
.content-surface li {
    color: var(--color-muted-strong);
}

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

.data-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1.5rem;
}

.data-table thead {
    background: rgba(15, 23, 42, 0.7);
}

.data-table th,
.data-table td {
    padding: 0.85rem 1rem;
    border-bottom: 1px solid rgba(148, 163, 184, 0.18);
    text-align: left;
    color: var(--color-muted-strong);
}

.data-table th {
    font-weight: 600;
    color: #f8fafc;
}

form {
    display: grid;
    gap: 1.4rem;
}

label {
    display: block;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 0.55rem;
    color: #f8fafc;
}

input[type="text"],
input[type="email"],
textarea {
    width: 100%;
    padding: 0.85rem 1rem;
    border-radius: 12px;
    border: 1px solid rgba(148, 163, 184, 0.28);
    background: rgba(14, 23, 42, 0.85);
    color: #f8fafc;
    font-family: inherit;
    font-size: 0.95rem;
    transition: border var(--transition), box-shadow var(--transition);
}

input[type="text"]:focus,
input[type="email"]:focus,
textarea:focus {
    outline: none;
    border-color: rgba(34, 211, 238, 0.6);
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.18);
}

textarea {
    min-height: 160px;
    resize: vertical;
}

.checkbox {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
}

.checkbox input {
    width: 20px;
    height: 20px;
    margin-top: 0.2rem;
    border-radius: 6px;
    border: 1px solid rgba(148, 163, 184, 0.4);
    accent-color: var(--color-primary);
}

.contact-panel {
    display: grid;
    gap: clamp(1.5rem, 4vw, 2.5rem);
}

.contact-card {
    border-radius: var(--radius);
    background: rgba(14, 23, 42, 0.75);
    border: 1px solid rgba(148, 163, 184, 0.14);
    padding: clamp(1.5rem, 4vw, 2rem);
}

.contact-card h3 {
    margin: 0 0 0.8rem;
}

.tag {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    border-radius: 999px;
    background: rgba(37, 99, 235, 0.16);
    color: var(--color-accent);
    padding: 0.35rem 0.9rem;
    font-size: 0.75rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.footer {
    margin-top: clamp(4rem, 10vw, 6rem);
    padding: clamp(2.5rem, 7vw, 3.5rem) 0;
    background: rgba(8, 14, 26, 0.9);
    border-top: 1px solid rgba(148, 163, 184, 0.18);
}

.footer__inner {
    display: grid;
    gap: 2rem;
}

.footer__meta {
    color: var(--color-muted);
    font-size: 0.85rem;
}

.footer__nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem 1.5rem;
    font-size: 0.9rem;
    color: var(--color-muted-strong);
}

.footer__nav a {
    color: inherit;
}

.lang-en {
    display: inline;
}

.lang-ko {
    display: none;
}

[data-lang="ko"] .lang-en {
    display: none;
}

[data-lang="ko"] .lang-ko {
    display: inline;
}

@media (max-width: 960px) {
    .site-header__inner {
        align-items: flex-start;
    }

    .nav-toggle {
        display: inline-flex;
        align-items: center;
        gap: 0.35rem;
    }

    .primary-nav {
        position: absolute;
        inset: calc(100% + 0.5rem) clamp(1rem, 4vw, 2rem) auto;
        background: rgba(12, 19, 35, 0.95);
        border: 1px solid rgba(148, 163, 184, 0.15);
        border-radius: var(--radius);
        padding: 1.25rem;
        flex-direction: column;
        align-items: stretch;
        gap: 1rem;
        box-shadow: var(--shadow-strong);
        opacity: 0;
        pointer-events: none;
        transform: translateY(-8px);
        transition: opacity var(--transition), transform var(--transition);
    }

    .primary-nav.is-open {
        opacity: 1;
        pointer-events: auto;
        transform: translateY(0);
    }

    .primary-nav__links {
        flex-direction: column;
        align-items: stretch;
    }

    .primary-nav__item {
        width: 100%;
    }

    .primary-nav__trigger {
        justify-content: space-between;
        width: 100%;
        padding: 0.75rem 0;
    }

    .primary-nav__trigger::after {
        margin-left: auto;
    }

    .sub-nav {
        position: static;
        margin: 0.35rem 0 0;
        padding: 0.75rem 0.95rem;
        border-radius: 12px;
        border: 1px solid rgba(148, 163, 184, 0.18);
        background: rgba(8, 14, 26, 0.9);
        box-shadow: none;
        opacity: 0;
        pointer-events: none;
        transform: none;
        max-height: 0;
        overflow: hidden;
        transition: opacity var(--transition), max-height var(--transition);
    }

    .primary-nav__item.is-open > .sub-nav {
        opacity: 1;
        pointer-events: auto;
        max-height: 360px;
    }

    .sub-nav__link {
        padding: 0.45rem 0;
    }

    .language-switch {
        align-self: flex-start;
    }
}

@media (max-width: 600px) {
    .hero__title {
        font-size: clamp(2.2rem, 9vw, 3rem);
    }

    section {
        padding: clamp(3.5rem, 16vw, 5rem) 0;
    }

    .cta-group {
        flex-direction: column;
        align-items: stretch;
    }

    .contact-panel {
        grid-template-columns: 1fr;
    }
}