/* ==========================================================
   Dalgubeol - Main (Intro Split) · v4 · Editorial Cinematic
   Deep Navy + Off-White 포인트 + Grain + Frame + Stagger
   ========================================================== */

:root {
    --intro-navy-deep: #050e1e;
    --intro-navy:      #0a1929;
    --intro-off:       #f5f1ea;   /* Warm off-white (고급감) */
    --intro-line:      rgba(245, 241, 234, 0.55);
    --intro-sub:       rgba(245, 241, 234, 0.62);
    --intro-hair:      rgba(245, 241, 234, 0.18);

    --intro-accent:       #ffffff;
    --intro-accent-2:     rgba(255, 255, 255, 0.78);
    --intro-accent-glow:  rgba(255, 255, 255, 0.35);
}

.page-main {
    overflow: hidden;
    background: var(--intro-navy-deep);
    --mx: 50%;
    --my: 50%;
}
.page-main .main-wrap { position: relative; }

/* ==========================================================
   오버레이 레이어들 (고정, 전체 화면)
   ========================================================== */

/* ---------- 오프닝 커튼 ---------- */
.intro-curtain {
    position: fixed; inset: 0; z-index: 90; pointer-events: none;
}
.intro-curtain__panel {
    position: absolute; top: 0; bottom: 0;
    width: 50%;
    background: var(--intro-navy-deep);
    transition: transform 1.2s cubic-bezier(.77,0,.175,1);
}
.intro-curtain__panel--l { left: 0;  transform: translateX(0); }
.intro-curtain__panel--r { right: 0; transform: translateX(0); }
.is-ready .intro-curtain__panel--l { transform: translateX(-101%); }
.is-ready .intro-curtain__panel--r { transform: translateX(101%); }

/* ---------- 필름 그레인 (SVG turbulence) ---------- */
.intro-grain {
    position: fixed; inset: 0; z-index: 10;
    pointer-events: none;
    opacity: 0.12;
    mix-blend-mode: overlay;
    background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='240' height='240' viewBox='0 0 240 240'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 1  0 0 0 0 1  0 0 0 0 1  0 0 0 0.6 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
    background-size: 240px 240px;
    animation: grainShift 5s steps(6) infinite;
}
@keyframes grainShift {
    0%   { transform: translate(0, 0); }
    20%  { transform: translate(-5%, 5%); }
    40%  { transform: translate(3%, -4%); }
    60%  { transform: translate(-2%, 3%); }
    80%  { transform: translate(4%, 2%); }
    100% { transform: translate(0, 0); }
}

/* ---------- 마우스 스포트라이트 ---------- */
.intro-spotlight {
    position: fixed; inset: 0; z-index: 4;
    pointer-events: none;
    background: radial-gradient(620px circle at var(--mx) var(--my),
                rgba(255, 255, 255, 0.08) 0%,
                rgba(255, 255, 255, 0) 60%);
    mix-blend-mode: screen;
    opacity: 0;
    transition: opacity 0.6s;
}
.is-ready .intro-spotlight { opacity: 1; }

/* ---------- 코너 프레임 ---------- */
.intro-frame {
    position: fixed; inset: 24px; z-index: 12;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.8s 1.3s cubic-bezier(.4,0,.2,1);
}
.is-ready .intro-frame { opacity: 1; }

.intro-frame__corner {
    position: absolute;
    width: 18px;
    height: 18px;
}
.intro-frame__corner::before,
.intro-frame__corner::after {
    content: "";
    position: absolute;
    background: var(--intro-off);
    opacity: 0.55;
}
.intro-frame__corner::before { width: 100%; height: 1px; }
.intro-frame__corner::after  { width: 1px;  height: 100%; }

.intro-frame__corner--tl { top: 0; left: 0; }
.intro-frame__corner--tl::before { top: 0;    left: 0; }
.intro-frame__corner--tl::after  { top: 0;    left: 0; }

.intro-frame__corner--tr { top: 0; right: 0; }
.intro-frame__corner--tr::before { top: 0;    right: 0; }
.intro-frame__corner--tr::after  { top: 0;    right: 0; }

.intro-frame__corner--bl { bottom: 0; left: 0; }
.intro-frame__corner--bl::before { bottom: 0; left: 0; }
.intro-frame__corner--bl::after  { bottom: 0; left: 0; }

.intro-frame__corner--br { bottom: 0; right: 0; }
.intro-frame__corner--br::before { bottom: 0; right: 0; }
.intro-frame__corner--br::after  { bottom: 0; right: 0; }

/* ==========================================================
   상단 바 / 사이드 인덱스
   ========================================================== */
.intro-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 30;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 32px 56px;
    pointer-events: none;
}
.intro-header > * { pointer-events: auto; }
.intro-logo img {
    height: 72px;
    filter: brightness(0) invert(1);
    opacity: 0.98;
    transition: transform 0.4s, opacity 0.4s;
}
.intro-logo:hover img { transform: scale(1.04); opacity: 1; }

/* ==========================================================
   Intro Split (본체)
   ========================================================== */
.intro-split {
    display: flex;
    width: 100%;
    height: 100vh;
    overflow: hidden;
    position: relative;
}

/* ---------- 패널 ---------- */
.intro-pane {
    position: relative;
    flex: 1 1 50%;
    height: 100%;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: left;
    color: var(--intro-off);
    transition: flex 0.9s cubic-bezier(.77,0,.175,1);
    cursor: pointer;
    text-decoration: none;
}

/* ---------- 배경 영상 (Ken Burns + Parallax wrapper 분리) ---------- */
.intro-pane__media {
    position: absolute;
    inset: 0;
    z-index: 0;
    overflow: hidden;
    background: #0b1a2c;
}
.intro-pane--right .intro-pane__media { background: #0a2e6b; }

/* 패럴럭스용 wrapper - JS가 transform 조작 */
.intro-pane__media-inner {
    position: absolute;
    inset: -6%;
    will-change: transform;
}
/* Ken Burns - 내부 video 에만 */
.intro-pane__media video,
.intro-pane__media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: brightness(0.38) saturate(0.78) contrast(1.08);
    transition: filter 0.8s cubic-bezier(.77,0,.175,1);
    animation: kenburns 28s ease-in-out infinite alternate;
}
.intro-pane--right .intro-pane__media video { animation-direction: alternate-reverse; }

@keyframes kenburns {
    0%   { transform: scale(1.04) translate(-1%, 0); }
    100% { transform: scale(1.12) translate(1%, -1%); }
}

/* ---------- 오버레이 ---------- */
.intro-pane__overlay {
    position: absolute;
    inset: 0;
    z-index: 1;
    transition: opacity 0.6s;
}
.intro-pane--left .intro-pane__overlay {
    background:
        radial-gradient(ellipse at 12% 100%, rgba(255,255,255,0.08) 0%, rgba(255,255,255,0) 55%),
        radial-gradient(ellipse at 30% 50%,  rgba(0,0,0,0)          0%, rgba(0,0,0,0.58)     100%),
        linear-gradient(180deg, rgba(0,0,0,0.52) 0%, rgba(0,0,0,0.90) 100%);
}
.intro-pane--right .intro-pane__overlay {
    background:
        radial-gradient(ellipse at 88% 0%,   rgba(255,255,255,0.06) 0%, rgba(255,255,255,0) 55%),
        radial-gradient(ellipse at 30% 50%,  rgba(8,38,90,0)        0%, rgba(8,38,90,0.55)    100%),
        linear-gradient(180deg, rgba(10,46,107,0.78) 0%, rgba(4,22,60,0.94) 100%);
}

/* ==========================================================
   타이포그래피 레이어
   ========================================================== */

/* ---------- 대형 아웃라인 넘버 ---------- */
.intro-pane__num {
    position: absolute;
    right: 5vw;
    bottom: -5vw;
    z-index: 1;
    font-size: 28vw;
    font-weight: 900;
    line-height: 0.9;
    letter-spacing: -0.04em;
    color: transparent;
    -webkit-text-stroke: 1px rgba(255,255,255,0.035);
    pointer-events: none;
    transition: -webkit-text-stroke-color 0.6s, transform 1s cubic-bezier(.77,0,.175,1);
    font-family: 'SCDream', 'Pretendard Variable', sans-serif;
    font-variant-numeric: tabular-nums;
}
.intro-pane--right .intro-pane__num { right: auto; left: 5vw; }

/* ---------- 뒤쪽 대형 영문 워터마크 ---------- */
.intro-pane__backtitle {
    position: absolute;
    right: -3vw;
    top: 50%;
    transform: translateY(-50%) rotate(-90deg);
    transform-origin: center;
    z-index: 1;
    font-size: clamp(110px, 14vw, 240px);
    font-weight: 700;
    letter-spacing: 0.08em;
    color: rgba(245, 241, 234, 0.035);
    pointer-events: none;
    white-space: nowrap;
    font-family: 'SCDream', 'Pretendard Variable', sans-serif;
    transition: color 0.8s;
}
.intro-pane--right .intro-pane__backtitle {
    right: auto;
    left: -3vw;
    transform: translateY(-50%) rotate(90deg);
}

/* ---------- 콘텐츠 컨테이너 ---------- */
.intro-pane__content {
    position: relative;
    z-index: 2;
    padding: 60px 88px;
    max-width: 680px;
    width: 100%;
    text-shadow: 0 2px 18px rgba(0, 0, 0, 0.45);
}

/* ---------- 좌측 얇은 라인 ---------- */
.intro-pane__line {
    width: 0;
    height: 1px;
    background: var(--intro-off);
    margin-bottom: 32px;
    opacity: 0;
}

/* ---------- 영문 배지 ---------- */
.intro-pane__en {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 11px;
    letter-spacing: 0.42em;
    font-weight: 600;
    margin: 0 0 36px;
    opacity: 0;
    transform: translateY(14px);
    color: var(--intro-off);
    text-transform: uppercase;
}
.intro-pane__en-dot {
    width: 6px;
    height: 6px;
    background: var(--intro-off);
    border-radius: 50%;
    box-shadow: 0 0 8px rgba(255,255,255,0.5);
    animation: enDotPulse 2s ease-in-out infinite;
}
@keyframes enDotPulse {
    0%, 100% { opacity: 1;   transform: scale(1); }
    50%      { opacity: 0.4; transform: scale(0.7); }
}

/* ---------- 메인 타이틀 (글자 단위 스태거) ---------- */
.intro-pane__title {
    font-size: clamp(52px, 6.5vw, 96px);
    font-weight: 700;
    letter-spacing: -0.035em;
    margin: 0 0 32px;
    line-height: 1.02;
    display: flex;
    flex-direction: column;
}
.intro-pane__title-line {
    display: block;
    overflow: hidden;
    padding: 0.04em 0;
    transition: color 0.5s cubic-bezier(.77,0,.175,1);
}
.intro-pane__title-line--2 {
    color: rgba(245, 241, 234, 0.72);
    font-weight: 300;
    letter-spacing: -0.02em;
}

/* Hover - 타이틀 전체 순백으로 */
.intro-pane:hover .intro-pane__title,
.intro-pane:hover .intro-pane__title-line,
.intro-pane:hover .intro-pane__title-line--2 {
    color: #ffffff;
}

/* JS로 래핑되는 .letter */
.intro-pane__title-line .letter {
    display: inline-block;
    opacity: 0;
    transform: translateY(110%);
}

/* ---------- 설명 ---------- */
.intro-pane__desc {
    font-size: clamp(15px, 1.1vw, 16px);
    line-height: 1.7;
    margin: 0 0 40px;
    font-weight: 300;
    opacity: 0;
    transform: translateY(14px);
    color: rgba(245, 241, 234, 0.85);
    max-width: 420px;
}

/* ---------- CTA ---------- */
.intro-pane__cta {
    display: inline-flex;
    align-items: center;
    gap: 20px;
    color: var(--intro-off);
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    opacity: 0;
    transform: translateY(14px);
    cursor: pointer;
}
.intro-pane__cta-label {
    position: relative;
    padding: 2px 2px;
}
.intro-pane__cta-label::after {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: -3px;
    height: 1px;
    background: var(--intro-off);
    transform: scaleX(1);
    transform-origin: left;
    transition: transform 0.6s cubic-bezier(.77,0,.175,1), background 0.3s;
}
.intro-pane__cta-circle {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    border: 1px solid rgba(255,255,255,0.5);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    transition: border-color 0.5s, box-shadow 0.5s;
}
.intro-pane__cta-circle::before {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--intro-off);
    transform: scale(0);
    transition: transform 0.6s cubic-bezier(.77,0,.175,1);
    border-radius: 50%;
}
.intro-pane__cta-circle svg {
    position: relative;
    z-index: 1;
    color: var(--intro-off);
    transition: transform 0.6s cubic-bezier(.77,0,.175,1), color 0.3s;
}

/* ==========================================================
   중앙 디바이더 + 엠블럼
   ========================================================== */
.intro-divider {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 5;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
    opacity: 0;
    transition: opacity 1s 1.2s;
}
.is-ready .intro-divider { opacity: 1; }

.intro-divider__emblem {
    flex-shrink: 0;
    width: 52px;
    height: 52px;
    border-radius: 50%;
    border: 1px solid rgba(255,255,255,0.28);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background: rgba(10, 25, 41, 0.35);
    backdrop-filter: blur(4px);
}
.intro-divider__emblem::before,
.intro-divider__emblem::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: 50%;
    border: 1px solid rgba(255,255,255,0.28);
    animation: emblemPulse 3.4s ease-out infinite;
}
.intro-divider__emblem::after { animation-delay: 1.7s; }
.intro-divider__dot {
    width: 5px; height: 5px;
    background: var(--intro-off);
    border-radius: 50%;
    box-shadow: 0 0 10px rgba(255,255,255,0.55);
}
@keyframes emblemPulse {
    0%   { transform: scale(1);   opacity: 0.55; }
    100% { transform: scale(2.3); opacity: 0; }
}

/* ==========================================================
   하단 힌트
   ========================================================== */
.intro-hint {
    position: absolute;
    left: 50%;
    bottom: 140px;
    transform: translateX(-50%);
    z-index: 5;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--intro-sub);
    font-size: 10px;
    letter-spacing: 0.4em;
    font-weight: 600;
    text-transform: uppercase;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.8s 1.6s;
    animation: hintPulse 2.6s ease-in-out infinite;
}
.is-ready .intro-hint { opacity: 1; }
.intro-hint__dot {
    width: 28px; height: 1px;
    background: var(--intro-off);
    opacity: 0.4;
}
@keyframes hintPulse {
    0%, 100% { filter: brightness(0.85); }
    50%      { filter: brightness(1.2); }
}

/* ==========================================================
   Hover 상태
   ========================================================== */
.intro-split:hover .intro-pane { flex: 1 1 42%; }
.intro-split:hover .intro-pane:hover { flex: 1 1 58%; }

.intro-pane:hover .intro-pane__media video,
.intro-pane:hover .intro-pane__media img {
    filter: brightness(0.58) saturate(0.95) contrast(1.08);
}
.intro-pane:hover .intro-pane__overlay { opacity: 0.82; }
.intro-pane:hover .intro-pane__num {
    -webkit-text-stroke-color: rgba(255,255,255,0.10);
    transform: translateY(-2%);
}
.intro-pane:hover .intro-pane__backtitle {
    color: rgba(245, 241, 234, 0.07);
}

.intro-pane:hover .intro-pane__cta-label::after { background: rgba(255,255,255,0); }
.intro-pane:hover .intro-pane__cta-circle {
    border-color: transparent;
    box-shadow: 0 0 28px rgba(255,255,255,0.18);
}
.intro-pane:hover .intro-pane__cta-circle::before { transform: scale(1.05); }
.intro-pane:hover .intro-pane__cta-circle svg { transform: translateX(5px); color: var(--intro-navy-deep); }

.intro-split:hover .intro-divider__emblem { opacity: 0; transform: scale(0.6); }
.intro-split:hover .intro-hint { opacity: 0; }

/* ==========================================================
   엔트리 애니메이션
   ========================================================== */
@keyframes lineExpand { to { width: 56px; opacity: 1; } }
@keyframes fadeUp     { to { opacity: 1; transform: translateY(0); } }
@keyframes letterRise { to { opacity: 1; transform: translateY(0); } }

.is-ready .intro-pane__line     { animation: lineExpand 0.9s 1.1s cubic-bezier(.77,0,.175,1) forwards; }
.is-ready .intro-pane__en       { animation: fadeUp    0.8s 1.3s cubic-bezier(.77,0,.175,1) forwards; }

/* 글자 스태거 - 1번째 줄, 2번째 줄 각각 순차 */
.is-ready .intro-pane__title-line[data-line="1"] .letter {
    animation: letterRise 0.9s cubic-bezier(.77,0,.175,1) forwards;
    animation-delay: calc(1.45s + var(--i, 0) * 0.045s);
}
.is-ready .intro-pane__title-line[data-line="2"] .letter {
    animation: letterRise 0.9s cubic-bezier(.77,0,.175,1) forwards;
    animation-delay: calc(1.7s + var(--i, 0) * 0.045s);
}

.is-ready .intro-pane__desc     { animation: fadeUp 0.8s 2.0s cubic-bezier(.77,0,.175,1) forwards; }
.is-ready .intro-pane__cta      { animation: fadeUp 0.8s 2.15s cubic-bezier(.77,0,.175,1) forwards; }

/* 우측 패널 약간 지연 */
.is-ready .intro-pane--right .intro-pane__line     { animation-delay: 1.2s; }
.is-ready .intro-pane--right .intro-pane__en       { animation-delay: 1.4s; }
.is-ready .intro-pane--right .intro-pane__title-line[data-line="1"] .letter { animation-delay: calc(1.55s + var(--i, 0) * 0.045s); }
.is-ready .intro-pane--right .intro-pane__title-line[data-line="2"] .letter { animation-delay: calc(1.8s + var(--i, 0) * 0.045s); }
.is-ready .intro-pane--right .intro-pane__desc     { animation-delay: 2.1s; }
.is-ready .intro-pane--right .intro-pane__cta      { animation-delay: 2.25s; }

/* ==========================================================
   Responsive
   ========================================================== */
@media (max-width: 1280px) {
    .intro-pane__content { padding: 48px 56px; }
    .intro-pane__title { font-size: clamp(46px, 6vw, 84px); margin: 0 0 28px; }
    .intro-pane__desc { margin-bottom: 32px; }
}

@media (max-width: 991px) {
    .intro-pane__line,
    .intro-pane__en,
    .intro-pane__desc { display: none; }
}

@media (max-width: 1024px) {
    .intro-header {
        grid-template-columns: auto 1fr;
        padding: 18px 24px;
    }
    .intro-meta { display: none; }
    .intro-logo img { height: 48px; }
    .intro-minimenu { font-size: 11px; gap: 12px; }

    /* 세로 적층 + 두 패널 동일 높이 (50vh × 2 = 100vh) */
    .intro-split {
        flex-direction: column;
        height: 100vh;
    }
    .intro-split:hover .intro-pane,
    .intro-split:hover .intro-pane:hover { flex: 1 1 50%; }
    .intro-pane {
        flex: 1 1 50%;
        height: 50vh;
        min-height: 360px;
    }
    .intro-pane__content { padding: 56px 40px; }
    .intro-pane__title { font-size: clamp(40px, 8vw, 64px); margin: 0 0 22px; }
    .intro-pane__desc { font-size: 15px; margin-bottom: 28px; }
    .intro-pane__num { font-size: 38vw; bottom: -10vw; opacity: 0.6; }
    .intro-pane__backtitle { display: none; }
    .intro-pane__en { font-size: 10px; letter-spacing: 0.36em; margin-bottom: 22px; }
    .intro-pane__line { margin-bottom: 20px; }

    .intro-divider, .intro-hint, .intro-frame { display: none; }

    .site-footer--main {
        position: static;
        background: #0d1b2a;
        color: #c7ccd3;
        pointer-events: auto;
    }
}

@media (max-width: 768px) {
    .intro-header { padding: 14px 18px; }
    .intro-logo img { height: 40px; }

    /* 화면이 좁아질수록 콘텐츠 영역 축소 */
    .intro-pane {
        height: auto;
        min-height: 50vh;
        flex: 1 1 50%;
    }
    .intro-split { height: auto; }
    .intro-pane__content { padding: 44px 28px; }
    .intro-pane__title { font-size: clamp(36px, 9vw, 52px); margin: 0 0 18px; }
    .intro-pane__desc  { font-size: 14px; line-height: 1.55; margin-bottom: 24px; }
    .intro-pane__en { font-size: 10px; letter-spacing: 0.3em; margin-bottom: 18px; }
    .intro-pane__num { font-size: 32vw; bottom: -8vw; }
    .intro-pane__cta-circle { width: 44px; height: 44px; }
}

@media (max-width: 576px) {
    .intro-header { padding: 12px 14px; }
    .intro-logo img { height: 34px; }

    /* 모바일 — 카드형 박스 디자인으로 전환 */
    .intro-split {
        height: auto;
        gap: 10px;
        padding: 10px;
        background: #0b1726;
    }
    .intro-pane {
        flex: 1 1 auto;
        min-height: 46vh;
        border-radius: 18px;
        overflow: hidden;
        box-shadow: 0 14px 30px rgba(0, 10, 30, 0.3);
    }
    .intro-pane__content { padding: 36px 22px 30px; }
    .intro-pane__title { font-size: clamp(30px, 9.5vw, 44px); margin: 0 0 14px; line-height: 1.05; }
    .intro-pane__desc  { font-size: 13.5px; line-height: 1.55; margin-bottom: 18px; }
    .intro-pane__keywords { margin-bottom: 24px; }
    .intro-pane__en { font-size: 9.5px; letter-spacing: 0.28em; margin-bottom: 14px; }
    .intro-pane__line { width: 32px; margin-bottom: 14px; }
    .intro-pane__cta-circle { width: 40px; height: 40px; }
    .intro-pane__cta-label { font-size: 12.5px; }
    .intro-pane__num { font-size: 30vw; bottom: -6vw; right: 4vw; opacity: 0.4; }
    .intro-pane--right .intro-pane__num { left: 4vw; }
}