/* 습지 탐방 노트 — 좌측 고정 사이드바 + 뉴스 용지 톤 (기존 상단 탭·파란 카드 스타일과 구분) */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --paper: #f4f1e8;
    --paper2: #ebe6d9;
    --ink: #1c1917;
    --muted: #57534e;
    --sidebar: #0f172a;
    --sidebar-muted: #94a3b8;
    --accent: #0d9488;
    --accent-hover: #0f766e;
    --border: #292524;
    --ease: cubic-bezier(0.33, 1, 0.68, 1);
}

html { scroll-behavior: smooth; }

body {
    font-family: "Gothic A1", "Noto Sans KR", system-ui, sans-serif;
    background: var(--paper);
    color: var(--ink);
    line-height: 1.75;
    font-size: 16px;
}

h1, h2, h3 {
    font-family: "Noto Serif KR", "Noto Sans KR", serif;
    font-weight: 700;
    letter-spacing: -0.02em;
}

a { color: var(--accent-hover); text-underline-offset: 3px; }
a:hover { color: var(--accent); }

/* —— 레이아웃 —— */
.shell {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 260px;
    flex-shrink: 0;
    background: var(--sidebar);
    color: #f8fafc;
    padding: 2rem 1.25rem;
    position: sticky;
    top: 0;
    align-self: flex-start;
    height: 100vh;
    overflow-y: auto;
    border-right: 4px solid var(--border);
}

.sidebar__brand {
    font-family: "Noto Serif KR", serif;
    font-size: 1.15rem;
    font-weight: 800;
    line-height: 1.35;
    text-decoration: none;
    color: #fff;
    display: block;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid rgba(148, 163, 184, 0.35);
}

.sidebar__nav {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}

.sidebar__a {
    display: block;
    padding: 0.55rem 0.65rem;
    color: var(--sidebar-muted);
    text-decoration: none;
    font-size: 0.92rem;
    font-weight: 500;
    border-left: 3px solid transparent;
    transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s;
}

.sidebar__a:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.06);
}

.sidebar__a.is-on {
    color: #fff;
    border-left-color: var(--accent);
    background: rgba(13, 148, 136, 0.15);
}

.sidebar__note {
    margin-top: 2rem;
    font-size: 0.78rem;
    color: var(--sidebar-muted);
    line-height: 1.55;
}

.main {
    flex: 1;
    min-width: 0;
    padding: 0 1.5rem 3rem;
}

.main__inner {
    max-width: 820px;
    margin: 0 auto;
}

/* 모바일 상단 바 */
.topbar {
    display: none;
    align-items: center;
    justify-content: space-between;
    padding: 0.85rem 1rem;
    background: var(--sidebar);
    color: #fff;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 3px solid var(--border);
}

.topbar__title {
    font-family: "Noto Serif KR", serif;
    font-weight: 800;
    font-size: 1rem;
}

.topbar__btn {
    width: 44px;
    height: 44px;
    border: 2px solid rgba(255, 255, 255, 0.35);
    background: transparent;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;
}

.topbar__btn span {
    display: block;
    width: 22px;
    height: 2px;
    background: #fff;
    transition: transform 0.25s var(--ease), opacity 0.2s;
}

.topbar__btn.is-open span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.topbar__btn.is-open span:nth-child(2) { opacity: 0; }
.topbar__btn.is-open span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

@media (max-width: 900px) {
    .shell { flex-direction: column; }
    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        height: 100%;
        z-index: 90;
        transform: translateX(-100%);
        transition: transform 0.35s var(--ease);
        box-shadow: 8px 0 40px rgba(0, 0, 0, 0.35);
    }
    .sidebar.is-open { transform: translateX(0); }
    .topbar { display: flex; }
    .main { padding-top: 0; }
}

.overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    z-index: 80;
    opacity: 0;
    transition: opacity 0.3s;
}

.overlay.is-on {
    display: block;
    opacity: 1;
}

/* —— 히어로 —— */
.hero {
    margin: 2rem 0 2.5rem;
    border: 3px solid var(--border);
    background: #fff;
    box-shadow: 8px 8px 0 rgba(28, 25, 23, 0.12);
}

.hero__pic {
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
}

.hero__pic img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.hero__body {
    padding: 1.5rem 1.35rem 1.75rem;
}

.hero__tag {
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--accent-hover);
    margin-bottom: 0.5rem;
}

.hero__h1 {
    font-size: clamp(1.75rem, 4.5vw, 2.35rem);
    margin-bottom: 0.65rem;
}

.hero__lead {
    color: var(--muted);
    font-size: 1.02rem;
    margin-bottom: 1.25rem;
}

.btn {
    display: inline-block;
    padding: 0.7rem 1.35rem;
    background: var(--accent);
    color: #fff !important;
    text-decoration: none;
    font-weight: 700;
    border: 3px solid var(--border);
    box-shadow: 4px 4px 0 var(--border);
    transition: transform 0.15s var(--ease), box-shadow 0.15s;
}

.btn:hover {
    transform: translate(2px, 2px);
    box-shadow: 2px 2px 0 var(--border);
}

/* —— 카드 그리드 —— */
.grid3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-bottom: 2.5rem;
}

.card {
    border: 3px solid var(--border);
    background: #fff;
    text-decoration: none;
    color: inherit;
    box-shadow: 6px 6px 0 rgba(28, 25, 23, 0.1);
    transition: transform 0.2s var(--ease);
}

.card:hover { transform: translateY(-4px); }

.card__img {
    aspect-ratio: 4/3;
    overflow: hidden;
    border-bottom: 3px solid var(--border);
}

.card__img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.card__bd { padding: 1rem 1rem 1.15rem; }
.card__h3 { font-size: 1.05rem; margin-bottom: 0.35rem; }
.card__p { font-size: 0.88rem; color: var(--muted); }

@media (max-width: 720px) {
    .grid3 { grid-template-columns: 1fr; }
}

/* —— 내부 페이지 —— */
.page-head {
    margin: 2rem 0 1.5rem;
    border: 3px solid var(--border);
    overflow: hidden;
    background: #fff;
    box-shadow: 6px 6px 0 rgba(28, 25, 23, 0.1);
}

.page-head img {
    width: 100%;
    display: block;
    aspect-ratio: 21/9;
    object-fit: cover;
}

.article {
    max-width: 640px;
}

.article__h1 {
    font-size: clamp(1.65rem, 3.5vw, 2.1rem);
    margin-bottom: 0.4rem;
}

.article__meta {
    font-size: 0.88rem;
    color: var(--muted);
    margin-bottom: 1.25rem;
}

.article p { margin-bottom: 1rem; }
.article h2 {
    font-size: 1.2rem;
    margin: 1.6rem 0 0.6rem;
}

/* —— 아코디언 —— */
.acc-item { border-bottom: 1px solid #d6d3d1; }
.acc-btn {
    width: 100%;
    text-align: left;
    padding: 1rem 0;
    background: none;
    border: none;
    font-family: inherit;
    font-size: 1.02rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.75rem;
    color: var(--ink);
}

.acc-btn::after {
    content: "+";
    font-size: 1.25rem;
    color: var(--accent-hover);
    transition: transform 0.25s;
}

.acc-item.is-open .acc-btn::after { transform: rotate(45deg); }

.acc-panel {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.45s var(--ease);
}

.acc-panel-inner {
    padding-bottom: 1rem;
    color: var(--muted);
    font-size: 0.95rem;
}

/* —— 갤러리 —— */
.gal {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.85rem;
    margin: 1.5rem 0;
}

.gal__cell {
    position: relative;
    aspect-ratio: 1;
    overflow: hidden;
    border: 3px solid var(--border);
    cursor: pointer;
    background: #fff;
}

.gal__cell img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s var(--ease);
}

.gal__cell:hover img { transform: scale(1.06); }

.gal__cap {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 0.5rem 0.65rem;
    font-size: 0.78rem;
    color: #fff;
    background: linear-gradient(transparent, rgba(15, 23, 42, 0.88));
}

.lightbox {
    position: fixed;
    inset: 0;
    z-index: 200;
    background: rgba(15, 23, 42, 0.94);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.25s, visibility 0.25s;
}

.lightbox.is-on { opacity: 1; visibility: visible; }

.lightbox__img {
    max-width: min(94vw, 1000px);
    max-height: 88vh;
    border: 4px solid #fff;
    box-shadow: 12px 12px 0 rgba(0, 0, 0, 0.4);
}

.lightbox__close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 48px;
    height: 48px;
    border: 3px solid #fff;
    background: var(--sidebar);
    color: #fff;
    font-size: 1.4rem;
    cursor: pointer;
    line-height: 1;
}

/* —— 문의 —— */
.contact-box {
    border: 3px solid var(--border);
    background: var(--paper2);
    padding: 1.5rem;
    margin: 1rem 0 1.5rem;
    box-shadow: 6px 6px 0 rgba(28, 25, 23, 0.12);
}

.contact-box__email {
    font-size: 1.08rem;
    font-weight: 800;
    word-break: break-all;
    color: var(--accent-hover);
}

/* —— 푸터 —— */
.ft {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 3px solid var(--border);
    font-size: 0.82rem;
    color: var(--muted);
}

.back-top {
    position: fixed;
    right: 1rem;
    bottom: 1rem;
    width: 48px;
    height: 48px;
    border: 3px solid var(--border);
    background: var(--accent);
    color: #fff;
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: 4px 4px 0 var(--border);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: opacity 0.25s, visibility 0.25s, transform 0.25s;
    z-index: 70;
}

.back-top.is-visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.reveal {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.55s var(--ease), transform 0.55s var(--ease);
}

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