:root {
    --bg: #fafafa;
    --fg: #1a1a1a;
    --muted: #6b6b6b;
    --line: #e5e5e5;
    --line-strong: #d4d4d4;
    --accent: #1a1a1a;
    --on-accent: #ffffff;
    --card-bg: #ffffff;
    --surface-hover: #f4f4f4;
    --header-bg: #ffffff;
    --shadow: 0 1px 3px rgba(0,0,0,.06), 0 8px 24px rgba(0,0,0,.04);
    --focus-ring: rgba(26,26,26,.18);
    --overlay: rgba(0,0,0,.45);
    --font-offset: 0px;
}
[data-theme="dark"] {
    --bg: #0a0a0a;
    --fg: #ededed;
    --muted: #9a9a9a;
    --line: #262626;
    --line-strong: #3a3a3a;
    --accent: #ffffff;
    --on-accent: #0a0a0a;
    --card-bg: #161616;
    --surface-hover: #1f1f1f;
    --header-bg: #0f0f0f;
    --shadow: 0 0 0 1px rgba(255,255,255,.04), 0 8px 28px rgba(0,0,0,.55);
    --focus-ring: rgba(255,255,255,.2);
    --overlay: rgba(0,0,0,.65);
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; height: 100%; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Pretendard", "Apple SD Gothic Neo", sans-serif;
    background: var(--bg);
    color: var(--fg);
    font-size: 16px;
    line-height: 1.6;
    transition: background .2s ease, color .2s ease;
    display: flex;
    flex-direction: column;
    height: 100vh;
}
header {
    border-bottom: 1px solid var(--line);
    padding: 9px 20px;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    background: var(--header-bg);
    transition: background .2s ease, border-color .2s ease;
    flex-shrink: 0;
}
header h1 {
    font-size: 16px;
    font-weight: 600;
    margin: 0;
    letter-spacing: -0.01em;
}
header .right {
    display: flex;
    align-items: center;
    gap: 12px;
}
header .stats {
    font-size: 13px;
    color: var(--muted);
}
.theme-toggle {
    background: none;
    border: 1px solid var(--line);
    color: var(--fg);
    width: 32px;
    height: 32px;
    border-radius: 8px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: inherit;
    font-size: 14px;
    line-height: 1;
    padding: 0;
    transition: all .15s ease;
}
.theme-toggle:hover { border-color: var(--line-strong); background: var(--surface-hover); }
.tree-toggle {
    display: none;
    background: none;
    border: 1px solid var(--line);
    color: var(--fg);
    width: 32px;
    height: 32px;
    border-radius: 8px;
    cursor: pointer;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: all .15s ease;
}
.tree-toggle:hover { border-color: var(--line-strong); background: var(--surface-hover); }
.tree-toggle svg { width: 16px; height: 16px; }
.tree-backdrop { display: none; }
.font-controls {
    display: inline-flex;
    border: 1px solid var(--line);
    border-radius: 8px;
    overflow: hidden;
    height: 32px;
}
.font-controls button {
    background: none;
    border: none;
    color: var(--fg);
    width: 32px;
    height: 32px;
    cursor: pointer;
    font-family: inherit;
    font-size: 13px;
    line-height: 1;
    padding: 0;
    transition: background .15s ease;
}
.font-controls button:hover { background: var(--surface-hover); }
.font-controls button + button { border-left: 1px solid var(--line); }
.font-controls .small { font-size: 11px; }
.font-controls .large { font-size: 15px; font-weight: 600; }
.theme-toggle svg { width: 16px; height: 16px; }
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }
.view-toggle {
    display: inline-flex;
    border: 1px solid var(--line);
    border-radius: 8px;
    overflow: hidden;
    height: 32px;
}
.view-toggle button {
    background: none;
    border: none;
    color: var(--muted);
    padding: 0 12px;
    font-size: 13px;
    cursor: pointer;
    font-family: inherit;
    transition: all .15s ease;
}
.view-toggle button.active {
    background: var(--accent);
    color: var(--on-accent);
}
.view-toggle button:not(.active):hover { color: var(--fg); }
.view-toggle button + button { border-left: 1px solid var(--line); }
.view-toggle button.active + button,
.view-toggle button + button.active { border-left-color: var(--accent); }

.list-view { animation: fadeIn .15s ease; }
.study-view { animation: fadeIn .15s ease; }
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.filters {
    display: flex;
    gap: 6px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}
.filter-chip {
    border: 1px solid var(--line);
    background: none;
    color: var(--muted);
    padding: 6px 12px;
    border-radius: 999px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
    transition: all .15s ease;
}
.filter-chip:hover { color: var(--fg); border-color: var(--line-strong); }
.filter-chip.active {
    background: var(--accent);
    color: var(--on-accent);
    border-color: var(--accent);
}
.list {
    list-style: none;
    margin: 0;
    padding: 0;
    border-top: 1px solid var(--line);
}
.list-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 8px;
    border-bottom: 1px solid var(--line);
    cursor: pointer;
    transition: background .12s ease;
    background: none;
    border-left: none;
    border-right: none;
    border-top: none;
    width: 100%;
    text-align: left;
    font-family: inherit;
    color: var(--fg);
    font-size: 15px;
}
.list-item:hover { background: var(--surface-hover); }
.list-item:focus { outline: none; background: var(--surface-hover); box-shadow: inset 2px 0 0 var(--accent); }
.list-item.done { opacity: 0.55; }
.list-item .li-id {
    font-size: 11px;
    color: var(--muted);
    min-width: 64px;
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.04em;
}
.list-item .li-text {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    color: var(--fg);
}
.list-item .li-text.empty { color: var(--muted); font-style: italic; }
.list-item .li-mtime {
    flex-shrink: 0;
    width: 130px;
    font-size: 11px;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.02em;
    text-align: right;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.list-item .li-actions {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
}
.list-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 8px;
    border-bottom: 1px solid var(--line-strong, var(--line));
    background: var(--surface-hover);
    font-size: 12px;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}
.list-header .li-id { min-width: 64px; }
.list-header .li-text { flex: 1; text-align: left; }
.list-header .li-mtime { width: 130px; text-align: right; }
.list-header-actions { display: flex; gap: 4px; align-items: center; }
.list-header .sort-btn {
    background: none;
    border: 1px solid transparent;
    color: var(--muted);
    cursor: pointer;
    padding: 4px 6px;
    border-radius: 6px;
    font: inherit;
    text-transform: inherit;
    letter-spacing: inherit;
    transition: all .12s ease;
}
.list-header .sort-btn:hover { color: var(--fg); border-color: var(--line); background: var(--card-bg); }
.list-header .sort-btn.active { color: var(--fg); border-color: var(--line); background: var(--card-bg); }
.list-header .list-icon-btn.active { color: var(--fg); border-color: var(--line); background: var(--card-bg); }
.list-header .sort-ind { font-size: 10px; margin-left: 2px; }
.list-header-spacer { width: 28px; height: 28px; display: inline-block; }
.list-icon-btn.danger { color: var(--muted); }
.list-icon-btn.danger:hover {
    color: #fff;
    background: #d33b3b;
    border-color: #d33b3b;
}
.list-icon-btn {
    background: none;
    border: 1px solid transparent;
    color: var(--muted);
    width: 28px;
    height: 28px;
    border-radius: 6px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: all .12s ease;
}
.list-icon-btn:hover { border-color: var(--line); color: var(--fg); }
.list-icon-btn.active { color: var(--fg); }
.list-icon-btn svg { width: 14px; height: 14px; }
.list-summary {
    font-size: 12px;
    color: var(--muted);
    padding: 12px 8px 0;
    text-align: right;
}
.app-body {
    flex: 1;
    display: flex;
    min-height: 0;
}
main {
    flex: 1;
    min-width: 0;
    overflow-y: auto;
}
.main-inner {
    max-width: 760px;
    margin: 0 auto;
    padding: 16px 20px 28px;
}

/* 우측 data 트리 패널 */
.tree-panel {
    width: 300px;
    flex-shrink: 0;
    overflow: hidden;
    border-left: 1px solid var(--line);
    background: var(--header-bg);
    display: flex;
    flex-direction: column;
    transition: background .2s ease, border-color .2s ease;
}
.tree-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 16px;
    border-bottom: 1px solid var(--line);
    position: sticky;
    top: 0;
    background: var(--header-bg);
    z-index: 1;
}
.tree-title {
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--muted);
}
.tree-refresh {
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    width: 26px;
    height: 26px;
    border-radius: 6px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    line-height: 1;
    padding: 0;
    transition: all .15s ease;
}
.tree-refresh:hover { color: var(--fg); border-color: var(--line-strong); background: var(--surface-hover); }
.tree-refresh.spin { animation: treeSpin .6s linear; }
@keyframes treeSpin { from { transform: rotate(0); } to { transform: rotate(360deg); } }
.tree { flex: 1; min-height: 0; overflow-y: auto; padding: 8px 0; }
.tree-foot {
    flex-shrink: 0;
    border-top: 1px solid var(--line);
    padding: 10px 16px;
    font-size: 12px;
    color: var(--muted);
    background: var(--header-bg);
    font-variant-numeric: tabular-nums;
}
.card-info {
    margin-top: 10px;
    text-align: center;
    font-size: 11px;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
}
.tree-head-btns { display: flex; gap: 6px; align-items: center; }
.tree-refresh.filter-active {
    color: var(--on-accent);
    background: var(--accent);
    border-color: var(--accent);
}
.tree-filter {
    flex-shrink: 0;
    border-bottom: 1px solid var(--line);
    padding: 10px 14px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    background: var(--header-bg);
}
.tree-filter[hidden] { display: none; }
.tf-row { display: flex; align-items: center; gap: 6px; }
.tf-label { font-size: 12px; color: var(--muted); width: 44px; flex-shrink: 0; }
.tf-input {
    background: var(--bg);
    color: var(--fg);
    border: 1px solid var(--line);
    border-radius: 6px;
    padding: 5px 8px;
    font-size: 12px;
    font-family: inherit;
}
.tf-input:focus { outline: none; border-color: var(--line-strong); }
.tf-num { width: 64px; }
select.tf-input { cursor: pointer; flex: 1; }
.tf-suffix { font-size: 12px; color: var(--muted); }
.tf-check { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--fg); cursor: pointer; }
.tf-check input { cursor: pointer; margin: 0; }
.tf-actions { justify-content: space-between; }
.tf-result { font-size: 11px; color: var(--muted); font-variant-numeric: tabular-nums; }
.tf-reset {
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
}
.tf-reset:hover { color: var(--fg); border-color: var(--line-strong); background: var(--surface-hover); }
.ans-tabs {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
    margin-bottom: 12px;
    border-bottom: 1px solid var(--line);
    padding-bottom: 8px;
}
.ans-tab {
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    padding: 5px 10px;
    border-radius: 999px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
    transition: all .12s ease;
}
.ans-tab:hover { color: var(--fg); border-color: var(--line-strong); }
.ans-tab.active { background: var(--accent); color: var(--on-accent); border-color: var(--accent); }
.ans-del {
    margin-top: 16px;
    background: none;
    border: 1px solid rgba(211, 59, 59, 0.45);
    color: #d33b3b;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
}
.ans-del:hover { color: #fff; background: #d33b3b; border-color: #d33b3b; }

/* ===== 카드 앞면 2버튼 (문제 풀기 / 답변 하기) ===== */
.front-actions { display: flex; gap: 6px; align-items: center; }
.card-mini-btn {
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
    transition: all .12s ease;
}
.card-mini-btn:hover:not(:disabled) { color: var(--fg); border-color: var(--line-strong); }
.card-mini-btn.quiz { border-color: var(--accent); color: var(--accent); }
.card-mini-btn.quiz:hover:not(:disabled) { background: var(--accent); color: var(--on-accent); }
.card-mini-btn:disabled { opacity: .4; cursor: default; }

/* ===== 객관식 풀이 ===== */
.quiz-progress {
    font-size: 12px;
    color: var(--muted);
    margin-bottom: 10px;
    padding: 6px 10px;
    border: 1px dashed var(--line);
    border-radius: 8px;
}
.quiz-progress.done {
    color: #2ea043;
    border-color: #2ea043;
    border-style: solid;
    font-weight: 600;
}
.quiz-wrap { display: flex; flex-direction: column; }
.quiz-question {
    font-size: calc(16px + var(--font-offset));
    line-height: 1.6;
    margin-bottom: 16px;
}
.quiz-options { display: flex; flex-direction: column; gap: 8px; }
.quiz-option {
    display: flex;
    align-items: center;
    gap: 10px;
    text-align: left;
    background: none;
    border: 1px solid var(--line);
    color: var(--fg);
    padding: 10px 14px;
    border-radius: 10px;
    font-size: calc(15px + var(--font-offset));
    line-height: 1.45;
    cursor: pointer;
    font-family: inherit;
    transition: all .12s ease;
}
.quiz-option:hover:not(:disabled) { border-color: var(--accent); background: var(--surface-hover); }
.quiz-option:disabled { cursor: default; }
.quiz-opt-num {
    flex: 0 0 auto;
    width: 22px;
    height: 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    border: 1px solid var(--line-strong);
    font-size: 12px;
    color: var(--muted);
}
.quiz-opt-text { flex: 1 1 auto; }
.quiz-option.correct { border-color: #2ea043; background: rgba(46, 160, 67, 0.14); }
.quiz-option.correct .quiz-opt-num { border-color: #2ea043; color: #2ea043; }
.quiz-option.wrong { border-color: #d33b3b; background: rgba(211, 59, 59, 0.12); }
.quiz-option.wrong .quiz-opt-num { border-color: #d33b3b; color: #d33b3b; }
.quiz-result { margin-top: 14px; font-size: 13px; font-weight: 600; }
.quiz-result.ok { color: #2ea043; }
.quiz-result.no { color: #d33b3b; }
.quiz-retry {
    margin-top: 10px;
    align-self: flex-start;
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
}
.quiz-retry:hover { color: var(--fg); border-color: var(--line-strong); }
.quiz-del {
    margin-top: 16px;
    align-self: flex-start;
    background: none;
    border: 1px solid rgba(211, 59, 59, 0.45);
    color: #d33b3b;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
}
.quiz-del:hover { color: #fff; background: #d33b3b; border-color: #d33b3b; }

/* ===== 플로팅 메모 버튼 + 메모 모달 ===== */
.memo-fab {
    position: fixed;
    right: 24px;
    bottom: 24px;
    width: 52px;
    height: 52px;
    border-radius: 50%;
    border: none;
    background: var(--accent);
    color: var(--on-accent);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow);
    z-index: 950;
    transition: transform .12s ease, filter .12s ease;
}
.memo-fab:hover { filter: brightness(1.1); transform: translateY(-2px); }
.memo-fab svg { width: 24px; height: 24px; }
.memo-modal { max-width: 560px; }
.memo-new { display: flex; flex-direction: column; gap: 8px; margin-bottom: 12px; }
.memo-new-input { min-height: 70px; }
.memo-add-btn { align-self: flex-end; }
.memo-status:empty { display: none; }
.memo-list { display: flex; flex-direction: column; gap: 10px; max-height: 50vh; overflow-y: auto; }
.memo-empty { color: var(--muted); font-size: 13px; text-align: center; padding: 20px; }
.memo-item {
    border: 1px solid var(--line);
    border-radius: 10px;
    padding: 10px 12px;
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.memo-meta { font-size: 11px; color: var(--muted); }
.memo-content { font-size: 13px; line-height: 1.55; word-break: break-word; }
.memo-edit-input { min-height: 70px; }
.memo-actions { display: flex; gap: 6px; justify-content: flex-end; }
.memo-act-btn {
    background: none;
    border: 1px solid var(--line);
    color: var(--muted);
    padding: 4px 10px;
    border-radius: 8px;
    font-size: 12px;
    cursor: pointer;
    font-family: inherit;
}
.memo-act-btn:hover { color: var(--fg); border-color: var(--line-strong); }
.memo-act-btn.primary { background: var(--accent); color: var(--on-accent); border-color: var(--accent); }
.memo-act-btn.danger { color: #d33b3b; border-color: rgba(211, 59, 59, 0.45); }
.memo-act-btn.danger:hover { background: #d33b3b; color: #fff; border-color: #d33b3b; }
.ctx-menu {
    position: fixed;
    z-index: 1200;
    background: var(--card-bg);
    border: 1px solid var(--line);
    border-radius: 8px;
    box-shadow: var(--shadow);
    padding: 4px;
    min-width: 150px;
    display: flex;
    flex-direction: column;
}
.ctx-item {
    background: none;
    border: none;
    color: var(--fg);
    text-align: left;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 13px;
    cursor: pointer;
    font-family: inherit;
}
.ctx-item:hover { background: var(--surface-hover); }
.ctx-item.danger { color: #d33b3b; }
.ctx-item.danger:hover { background: #d33b3b; color: #fff; }
.tree-dir.drop-target,
.tree-card.drop-target {
    background: var(--accent);
    color: var(--on-accent);
    outline: 2px dashed var(--accent);
    outline-offset: -2px;
}
.tree-dir {
    display: flex;
    align-items: center;
    gap: 6px;
    width: 100%;
    padding: 8px 14px;
    background: none;
    border: none;
    color: var(--fg);
    font-family: inherit;
    font-size: 14px;
    cursor: pointer;
    text-align: left;
    transition: background .12s ease;
}
.tree-dir:hover { background: var(--surface-hover); }
.tree-dir.active { font-weight: 600; }
.tree-dir .tree-arrow {
    width: 12px;
    flex-shrink: 0;
    font-size: 10px;
    color: var(--muted);
    text-align: center;
}
.tree-dir .tree-node-name {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.tree-dir .tree-count {
    margin-left: auto;
    flex-shrink: 0;
    font-size: 11px;
    color: var(--muted);
    font-variant-numeric: tabular-nums;
}
.tree-card {
    display: block;
    width: 100%;
    padding: 6px 14px 6px 32px;
    background: none;
    border: none;
    border-left: 2px solid transparent;
    color: var(--muted);
    font-family: inherit;
    font-size: 13px;
    cursor: pointer;
    text-align: left;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    transition: background .12s ease, color .12s ease;
}
.tree-card:hover { background: var(--surface-hover); color: var(--fg); }
.tree-card.active {
    color: var(--fg);
    background: var(--surface-hover);
    border-left-color: var(--accent);
    font-weight: 500;
}
.tree-empty {
    padding: 6px 14px 6px 32px;
    font-size: 12px;
    color: var(--muted);
    font-style: italic;
}
.categories {
    display: flex;
    gap: 8px;
    margin-bottom: 32px;
    flex-wrap: wrap;
}
.cat-btn {
    border: 1px solid var(--line);
    background: var(--card-bg);
    padding: 8px 16px;
    border-radius: 999px;
    font-size: 14px;
    cursor: pointer;
    color: var(--fg);
    transition: all .15s ease;
}
.cat-btn:hover { border-color: var(--line-strong); background: var(--surface-hover); }
.cat-btn.active {
    background: var(--accent);
    color: var(--on-accent);
    border-color: var(--accent);
}
.cat-btn.active:hover { background: var(--accent); }
.card-area {
    perspective: 1200px;
    margin-bottom: 12px;
}
.card {
    position: relative;
    min-height: 220px;
    border-radius: 12px;
    transform-style: preserve-3d;
    transition: transform .5s cubic-bezier(.4,0,.2,1), min-height .3s ease;
}
.flip-hint {
    cursor: pointer;
    user-select: none;
    padding: 4px 8px;
    margin: -4px -8px;
    border-radius: 6px;
    transition: background .15s ease, color .15s ease;
}
.flip-hint:hover {
    background: var(--surface-hover);
    color: var(--fg);
}
.card.flipped { transform: rotateY(180deg); }
.card-face {
    position: absolute;
    inset: 0;
    background: var(--card-bg);
    border: 1px solid var(--line);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 22px 24px;
    display: flex;
    flex-direction: column;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}
.card-back { transform: rotateY(180deg); }
.card-label {
    font-size: 11px;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 10px;
}
.card-content {
    flex: 1;
    font-size: calc(16px + var(--font-offset));
    line-height: 1.6;
    white-space: pre-wrap;
    word-break: keep-all;
}
.card-image {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 8px;
    background: var(--bg);
    cursor: zoom-in;
}
.card-image + .card-text { margin-top: 12px; }
.lightbox {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.92);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    cursor: zoom-out;
    padding: 24px;
    box-sizing: border-box;
}
.lightbox-img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    user-select: none;
    -webkit-user-drag: none;
    border-radius: 4px;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.6);
}
.lightbox-close {
    position: absolute;
    top: 12px;
    right: 16px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    font-size: 24px;
    line-height: 1;
    cursor: pointer;
    padding: 6px 12px;
    border-radius: 8px;
}
.lightbox-close:hover { background: rgba(255, 255, 255, 0.18); }
.card-pdf-wrap {
    display: flex;
    flex-direction: column;
    gap: 6px;
    width: 100%;
    flex: 1;
    min-height: 0;
}
.card-pdf {
    width: 100%;
    height: 100%;
    min-height: 480px;
    flex: 1;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--bg);
}
.card-face:has(.card-pdf) {
    padding: 16px 16px 12px;
}
.card-face:has(.card-pdf) .card-label {
    margin-bottom: 8px;
}
.card-face:has(.card-pdf) .card-content {
    display: flex;
    flex-direction: column;
    min-height: 0;
}
.card-face:has(.card-pdf) .card-footer {
    margin-top: 8px;
}
.card-pdf-link {
    align-self: flex-end;
    font-size: 12px;
    color: var(--muted);
    text-decoration: none;
}
.card-pdf-link:hover { color: var(--fg); text-decoration: underline; }
.card-pdf-wrap + .card-text { margin-top: 12px; }
.card-text { white-space: pre-wrap; }
.card-text.markdown-body { white-space: normal; }
.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4,
.markdown-body h5,
.markdown-body h6 {
    margin: 18px 0 8px;
    font-weight: 600;
    line-height: 1.3;
    letter-spacing: -0.01em;
}
.markdown-body > :first-child { margin-top: 0; }
.markdown-body > :last-child { margin-bottom: 0; }
.markdown-body h1 { font-size: calc(22px + var(--font-offset)); }
.markdown-body h2 { font-size: calc(19px + var(--font-offset)); padding-bottom: 6px; border-bottom: 1px solid var(--line); }
.markdown-body h3 { font-size: calc(17px + var(--font-offset)); }
.markdown-body h4 { font-size: calc(16px + var(--font-offset)); color: var(--muted); }
.markdown-body p { margin: 10px 0; }
.markdown-body ul,
.markdown-body ol {
    margin: 10px 0;
    padding-left: 22px;
}
.markdown-body li { margin: 4px 0; }
.markdown-body li > p { margin: 4px 0; }
.markdown-body strong { font-weight: 600; }
.markdown-body em { font-style: italic; }
.markdown-body blockquote {
    margin: 12px 0;
    padding: 8px 14px;
    border-left: 3px solid var(--line-strong);
    color: var(--muted);
    background: var(--surface-hover);
    border-radius: 0 6px 6px 0;
}
.markdown-body code {
    background: var(--surface-hover);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
    font-size: 0.9em;
}
.markdown-body pre {
    background: var(--surface-hover);
    padding: 12px 14px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 12px 0;
}
.markdown-body pre code {
    background: none;
    padding: 0;
    font-size: 0.88em;
}
.markdown-body hr {
    border: none;
    border-top: 1px solid var(--line);
    margin: 16px 0;
}
.markdown-body a {
    color: var(--fg);
    text-decoration: underline;
    text-underline-offset: 2px;
}
.markdown-body a:hover { color: var(--accent); }
.markdown-body table {
    border-collapse: collapse;
    margin: 12px 0;
    width: 100%;
    font-size: 14px;
}
.markdown-body th,
.markdown-body td {
    border: 1px solid var(--line);
    padding: 6px 10px;
    text-align: left;
}
.markdown-body th { background: var(--surface-hover); font-weight: 600; }
.card-empty {
    color: var(--muted);
    font-style: italic;
}
.card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 10px;
    border-top: 1px solid var(--line);
    margin-top: 10px;
    font-size: 12px;
    color: var(--muted);
}
.controls {
    display: flex;
    gap: 5px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 10px;
}
.btn {
    border: 1px solid var(--line);
    background: var(--card-bg);
    padding: 6px 12px;
    border-radius: 7px;
    font-size: 13px;
    cursor: pointer;
    color: var(--fg);
    transition: all .15s ease;
    font-family: inherit;
}
.btn:hover:not(:disabled) { border-color: var(--line-strong); background: var(--surface-hover); }
.btn:disabled {
    opacity: 0.45;
    cursor: not-allowed;
    color: var(--muted);
    background: transparent;
}
.btn.primary {
    background: var(--accent);
    color: var(--on-accent);
    border-color: var(--accent);
}
.btn.primary:hover:not(:disabled) { opacity: 0.9; background: var(--accent); }
.btn.danger {
    color: #d33b3b;
    border-color: rgba(211, 59, 59, 0.45);
}
.btn.danger:hover:not(:disabled) {
    color: #fff;
    background: #d33b3b;
    border-color: #d33b3b;
}
.actions {
    display: flex;
    gap: 6px;
    justify-content: center;
    flex-wrap: wrap;
}
.action-btn {
    background: none;
    border: 1px solid var(--line);
    padding: 6px 11px;
    border-radius: 7px;
    cursor: pointer;
    font-size: 12px;
    color: var(--muted);
    font-family: inherit;
    transition: all .15s ease;
}
.action-btn:hover { color: var(--fg); border-color: var(--line-strong); background: var(--surface-hover); }
.action-btn.active {
    background: var(--accent);
    color: var(--on-accent);
    border-color: var(--accent);
}
.action-btn.active:hover { background: var(--accent); }
.empty-state {
    text-align: center;
    padding: 80px 24px;
    color: var(--muted);
}
.progress {
    height: 2px;
    background: var(--line);
    border-radius: 2px;
    margin-bottom: 10px;
    overflow: hidden;
}
.progress-bar {
    height: 100%;
    background: var(--accent);
    transition: width .3s ease;
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: var(--overlay);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    z-index: 1000;
    animation: fadeIn .15s ease;
}
.modal {
    background: var(--card-bg);
    color: var(--fg);
    border: 1px solid var(--line);
    border-radius: 12px;
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 720px;
    max-height: calc(100vh - 48px);
    display: flex;
    flex-direction: column;
}
.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--line);
}
.modal-title {
    margin: 0;
    font-size: 14px;
    font-weight: 600;
}
.modal-close {
    background: none;
    border: none;
    color: var(--muted);
    cursor: pointer;
    font-size: 18px;
    line-height: 1;
    padding: 4px 8px;
    border-radius: 6px;
}
.modal-close:hover { background: var(--surface-hover); color: var(--fg); }
.modal-body { padding: 16px 20px; overflow-y: auto; flex: 1; }
.modal-textarea {
    width: 100%;
    min-height: 360px;
    background: var(--bg);
    color: var(--fg);
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 12px;
    font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
    font-size: 13px;
    line-height: 1.6;
    resize: vertical;
}
.modal-textarea:focus { outline: none; border-color: var(--line-strong); box-shadow: 0 0 0 3px var(--focus-ring); }
.modal-label {
    display: block;
    font-size: 12px;
    color: var(--muted);
    margin: 12px 0 6px;
}
.modal-label:first-child { margin-top: 0; }
.modal-input {
    width: 100%;
    background: var(--bg);
    color: var(--fg);
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 14px;
    line-height: 1.4;
    box-sizing: border-box;
}
.modal-input:focus { outline: none; border-color: var(--line-strong); box-shadow: 0 0 0 3px var(--focus-ring); }
.modal-hint {
    font-size: 12px;
    color: var(--muted);
    margin: 8px 0 0;
}
.modal-footer {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: flex-end;
    align-items: center;
    padding: 12px 20px;
    border-top: 1px solid var(--line);
}
.modal-status {
    flex: 1 1 100%;
    min-width: 0;
    font-size: 12px;
    color: var(--muted);
    word-break: break-all;
    overflow-wrap: anywhere;
    line-height: 1.4;
}
.modal-status:empty { display: none; }
.modal-status.error { color: #d4453d; }
.modal-status.ok { color: var(--fg); }

@media (max-width: 600px) {
    body { height: auto; min-height: 100vh; }
    .app-body { flex-direction: column; }
    main { overflow-y: visible; }
    .main-inner { padding: 24px 16px 80px; }
    .tree-toggle { display: inline-flex; }
    .tree-panel {
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        width: min(320px, 85vw);
        max-height: none;
        border-left: 1px solid var(--line);
        border-top: none;
        transform: translateX(100%);
        transition: transform .25s ease;
        z-index: 1100;
        box-shadow: var(--shadow);
    }
    body.tree-open .tree-panel { transform: translateX(0); }
    .tree-backdrop {
        display: block;
        position: fixed;
        inset: 0;
        background: var(--overlay);
        z-index: 1090;
        opacity: 0;
        pointer-events: none;
        transition: opacity .25s ease;
    }
    body.tree-open .tree-backdrop { opacity: 1; pointer-events: auto; }
    body.tree-open { overflow: hidden; }
    header { flex-wrap: wrap; gap: 8px; padding: 12px 16px; }
    header .right { gap: 8px; }
    header .stats { display: none; }
    .card-face { padding: 24px; }
    .card-content { font-size: calc(16px + var(--font-offset)); }
    .card { min-height: 280px; }
    .list-item { padding: 12px 4px; font-size: 14px; }
    .list-item .li-id { min-width: 52px; }
    .list-item .li-mtime, .list-header .li-mtime { width: 76px; font-size: 10px; }
    .modal { max-height: calc(100vh - 24px); }
    .modal-textarea { min-height: 280px; }
}