/* ==========================================
   COLUMN PAGE — Editorial Redesign
   "COLUMN" 좌측 대형 + 1열 인덱스 리스트
   ========================================== */

/* Utility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}


/* ==========================================
   HERO — "COLUMN" 좌측 + 설명 우측
   ========================================== */
.column-hero {
    padding: 140px 0 0;
    background: #ffffff;
    overflow: hidden;
}

.column-hero__layout {
    display: grid;
    grid-template-columns: auto 1fr;
    align-items: flex-end;
    gap: clamp(24px, 4vw, 48px);
    margin-bottom: 0;
}

.column-hero__typo {
    overflow: hidden;
}

.column-hero__title {
    margin: 0;
    line-height: 1;
}

.column-hero__word {
    display: block;
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(72px, 14vw, 180px);
    font-weight: 400;
    color: #0f172a;
    letter-spacing: -0.03em;
    line-height: 0.82;
    animation: colReveal 0.9s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes colReveal {
    from { opacity: 0; transform: translateY(80%); }
    to { opacity: 1; transform: translateY(0); }
}

.column-hero__info {
    padding-bottom: 16px;
    animation: colFade 0.6s ease 0.4s both;
}

@keyframes colFade {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

.column-hero__desc {
    font-size: clamp(18px, 2.5vw, 24px);
    font-weight: 700;
    color: #0f172a;
    line-height: 1.45;
    margin: 0 0 12px;
    letter-spacing: -0.02em;
}

.column-hero__sub {
    font-size: 14px;
    color: #64748b;
    line-height: 1.7;
    margin: 0;
}

/* 하단 바 */
.column-hero__bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding: 20px 0;
    margin-top: 24px;
    border-top: 2px solid #0f172a;
    border-bottom: 1px solid #e2e8f0;
    animation: colFade 0.5s ease 0.6s both;
}

.column-hero__bar-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.column-hero__bar-indicator {
    width: 8px;
    height: 8px;
    background: #0f172a;
    flex-shrink: 0;
}

.column-hero__bar-label {
    font-size: 13px;
    font-weight: 500;
    color: #64748b;
    margin: 0;
}

.column-hero__bar-right {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.column-hero__bar-freq {
    font-size: 11px;
    font-weight: 600;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.column-hero__bar-sep { color: #cbd5e1; font-size: 12px; }

.column-hero__bar-link {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 12px;
    font-weight: 600;
    color: #2563eb;
    text-decoration: none;
    transition: gap 0.3s;
}

.column-hero__bar-link:hover { gap: 9px; }


/* ==========================================
   LIST SECTION
   ========================================== */
.column-list-section {
    padding: 64px 0 120px;
    background: #f8fafc;
}

.column-list-header { margin-bottom: 0; }

.column-list-header__top {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin-bottom: 16px;
}

.column-list-header__title {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 800;
    color: #0f172a;
    letter-spacing: -0.03em;
    margin: 0;
}

.column-list-header__count { font-size: 13px; color: #64748b; letter-spacing: 0.05em; }
.column-list-header__count span { font-weight: 700; color: #0f172a; font-size: 14px; }

.column-list-header__line {
    width: 100%;
    height: 2px;
    background: #0f172a;
    transform-origin: left;
    transform: scaleX(0);
    transition: transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.column-list-header__line.is-visible { transform: scaleX(1); }


/* ==========================================
   ARTICLE — 1열 풀와이드 에디토리얼
   ========================================== */
.column-articles {
    display: flex;
    flex-direction: column;
}

.column-article {
    position: relative;
    border-bottom: 1px solid #e2e8f0;
}

.column-article__link {
    display: grid;
    grid-template-columns: 80px 1fr 48px;
    align-items: start;
    gap: 24px;
    padding: 32px 0;
    text-decoration: none;
    color: inherit;
    transition: padding-left 0.3s ease;
}

.column-article:hover .column-article__link { padding-left: 16px; }

/* 마지막 편 (결론) */
.column-article--final { border-bottom: 2px solid #0f172a; }


/* ==========================================
   NUMBER
   ========================================== */
.column-article__number {
    font-family: 'Bebas Neue', sans-serif;
    font-size: clamp(36px, 4.5vw, 56px);
    font-weight: 400;
    color: #cbd5e1;
    line-height: 0.85;
    letter-spacing: -0.02em;
    padding-top: 2px;
    transition: color 0.3s;
}

.column-article:hover .column-article__number { color: #0f172a; }


/* ==========================================
   BODY
   ========================================== */
.column-article__body {
    display: flex;
    flex-direction: column;
    gap: 8px;
    min-width: 0;
}

.column-article__meta {
    display: flex;
    align-items: center;
    gap: 10px;
}

.column-article__cat {
    font-size: 11px;
    font-weight: 600;
    color: #64748b;
    padding: 3px 10px;
    border: 1px solid #e2e8f0;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    transition: all 0.3s;
}

.column-article:hover .column-article__cat { border-color: #0f172a; color: #0f172a; }

.column-article__date { font-size: 12px; color: #94a3b8; }

.column-article__title {
    font-size: clamp(16px, 2vw, 22px);
    font-weight: 800;
    color: #0f172a;
    letter-spacing: -0.02em;
    line-height: 1.4;
    margin: 0;
    transition: color 0.3s;
}

.column-article:hover .column-article__title { color: #2563eb; }


/* ==========================================
   REVEAL — 호버 시 excerpt 슬라이드
   ========================================== */
.column-article__reveal {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.3s ease;
    opacity: 0;
}

.column-article:hover .column-article__reveal {
    max-height: 120px;
    opacity: 1;
}

.column-article__excerpt {
    font-size: 14px;
    color: #64748b;
    line-height: 1.7;
    margin: 4px 0 8px;
}

.column-article__tags { display: flex; flex-wrap: wrap; gap: 6px; }

.column-article__tag {
    font-size: 11px;
    font-weight: 600;
    color: #94a3b8;
    padding: 3px 10px;
    border: 1px solid #e2e8f0;
    transition: all 0.3s;
}

.column-article:hover .column-article__tag {
    border-color: rgba(37, 99, 235, 0.3);
    color: #2563eb;
}


/* ==========================================
   ARROW
   ========================================== */
.column-article__arrow {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #cbd5e1;
    border: 1px solid #e2e8f0;
    flex-shrink: 0;
    margin-top: 2px;
    transition: all 0.3s;
}

.column-article:hover .column-article__arrow {
    background: #0f172a;
    border-color: #0f172a;
    color: #fff;
    transform: translate(3px, -3px);
}


/* ==========================================
   HOVER PREVIEW
   ========================================== */
.column-article__preview {
    position: absolute;
    pointer-events: none;
    opacity: 0;
    z-index: 10;
    width: 360px;
    overflow: hidden;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.14);
    transition: opacity 0.25s;
}

.column-article__preview.is-visible { opacity: 1; }
.column-article__preview img { width: 100%; height: auto; display: block; }


/* ==========================================
   EDITOR'S NOTE (블로그와 동일 패턴)
   ========================================== */
.editor-note { margin-top: 48px; }

.editor-note__accordion { background: #fff; border: 1px solid #e2e8f0; }

.editor-note__trigger {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    background: none;
    border: none;
    cursor: pointer;
    transition: background 0.2s;
}

.editor-note__trigger:hover { background: #f8fafc; }
.editor-note__trigger-left { display: flex; align-items: center; gap: 16px; }

.editor-note__label {
    font-size: 11px;
    font-weight: 700;
    color: #2563eb;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 5px 12px;
    border: 1px solid rgba(37, 99, 235, 0.3);
}

.editor-note__trigger-title { font-size: 15px; font-weight: 600; color: #0f172a; }
.editor-note__arrow { color: #94a3b8; transition: transform 0.3s; }
.editor-note__accordion.is-open .editor-note__arrow { transform: rotate(180deg); }

.editor-note__panel { max-height: 0; overflow: hidden; transition: max-height 0.3s; }
.editor-note__accordion.is-open .editor-note__panel { max-height: 500px; }

.editor-note__content { padding: 0 24px 24px; }

.editor-note__text { font-size: 14px; line-height: 1.8; color: #64748b; margin-bottom: 20px; }
.editor-note__text strong { color: #0f172a; font-weight: 600; }

.editor-note__comparison { display: grid; grid-template-columns: 1fr 1fr; border-top: 2px solid #0f172a; }

.editor-note__item { padding: 20px 20px 20px 0; }
.editor-note__item--seo { border-right: 1px solid #e2e8f0; padding-right: 20px; }
.editor-note__item--geo { padding-left: 20px; }

.editor-note__item-label { font-size: 13px; font-weight: 700; margin: 0 0 8px; text-transform: uppercase; letter-spacing: 0.02em; }
.editor-note__item--seo .editor-note__item-label { color: #64748b; }
.editor-note__item--geo .editor-note__item-label { color: #2563eb; }

.editor-note__item-desc { font-size: 13px; color: #94a3b8; line-height: 1.6; margin: 0; }

.editor-note__link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 20px;
    font-size: 13px;
    font-weight: 600;
    color: #2563eb;
    text-decoration: none;
    transition: gap 0.2s;
}

.editor-note__link:hover { gap: 10px; }


/* ==========================================
   CTA
   ========================================== */
.column-cta {
    margin-top: 80px;
    padding-top: 48px;
    border-top: 1px solid #e2e8f0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
}

.column-cta__text { font-size: 18px; color: #0f172a; margin: 0; line-height: 1.6; font-weight: 500; }
.column-cta__text strong { font-weight: 700; color: #2563eb; }

.column-cta__btn {
    background: #0f172a;
    color: #fff;
    padding: 14px 32px;
    font-size: 14px;
    font-weight: 600;
    border-radius: 0;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    transition: all 0.3s;
    white-space: nowrap;
    flex-shrink: 0;
}

.column-cta__btn:hover { background: #2563eb; }
.column-cta__btn svg { transition: transform 0.3s; }
.column-cta__btn:hover svg { transform: translateX(4px); }


/* ==========================================
   SCROLL REVEAL
   ========================================== */
.scroll-reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.scroll-reveal.is-visible { opacity: 1; transform: translateY(0); }


/* ==========================================
   RESPONSIVE
   ========================================== */
@media (max-width: 768px) {
    .column-hero { padding: 120px 0 0; }

    .column-hero__layout {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .column-hero__word { font-size: clamp(56px, 16vw, 80px); }

    .column-hero__desc { font-size: 18px; }

    .column-hero__bar {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
        padding: 16px 0;
        margin-top: 20px;
    }

    .column-article__link {
        grid-template-columns: 48px 1fr 40px;
        gap: 14px;
        padding: 24px 0;
    }

    .column-article:hover .column-article__link { padding-left: 0; }

    .column-article__number { font-size: 28px; }
    .column-article__title { font-size: 16px; }
    .column-article__tag { font-size: 10px; padding: 3px 8px; }
    .column-article__arrow { width: 36px; height: 36px; }
    .column-article__preview { display: none; }

    /* 모바일에서 reveal 항상 표시 */
    .column-article__reveal {
        max-height: none;
        opacity: 1;
    }

    .column-cta { flex-direction: column; align-items: flex-start; gap: 24px; margin-top: 60px; padding-top: 32px; }

    .editor-note__trigger { padding: 16px 20px; }
    .editor-note__content { padding: 0 20px 20px; }
    .editor-note__comparison { grid-template-columns: 1fr; }
    .editor-note__item--seo { border-right: none; border-bottom: 1px solid #e2e8f0; padding: 16px 0; }
    .editor-note__item--geo { padding: 16px 0 0; }
}

@media (max-width: 480px) {
    .column-hero__word { font-size: 48px; }
    .column-article__link { grid-template-columns: 40px 1fr 36px; gap: 10px; }
    .column-article__number { font-size: 24px; }
    .column-article__title { font-size: 15px; }
}