:root {
    color-scheme: light;
    --bg: #f4f7fb;
    --panel: #ffffff;
    --text: #172033;
    --muted: #6d7789;
    --line: #dfe5ee;
    --primary: #2764e7;
    --primary-dark: #174ab8;
    --success: #147a4b;
    --danger: #bd2c37;
    --shadow: 0 18px 45px rgba(30, 46, 80, .10);
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text);
}

a { color: inherit; }

.shell {
    width: min(920px, calc(100% - 28px));
    margin: 0 auto;
    padding: 28px 0 56px;
}

.hero {
    text-align: center;
    padding: 34px 12px 24px;
}

.hero h1, .panel h1 {
    margin: 4px 0 10px;
    font-size: clamp(2rem, 6vw, 3.5rem);
    letter-spacing: -.04em;
}

.hero p, .lead, .note {
    color: var(--muted);
    line-height: 1.7;
}

.eyebrow {
    margin: 0;
    color: var(--primary);
    font-size: .78rem;
    font-weight: 800;
    letter-spacing: .18em;
}

.choice-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
}

.choice-card {
    display: block;
    min-height: 230px;
    padding: 30px;
    border: 1px solid var(--line);
    border-radius: 28px;
    background: var(--panel);
    box-shadow: var(--shadow);
    text-decoration: none;
    transition: transform .18s ease, box-shadow .18s ease;
}

.choice-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 22px 50px rgba(30, 46, 80, .15);
}

.choice-card h2 {
    margin: 18px 0 6px;
    font-size: 1.7rem;
}

.choice-card p { color: var(--muted); }

.choice-icon {
    display: grid;
    place-items: center;
    width: 62px;
    height: 62px;
    border-radius: 20px;
    background: #e9f0ff;
    color: var(--primary);
    font-size: 2rem;
    font-weight: 800;
}

.note {
    margin: 24px auto 0;
    text-align: center;
}

.back-link {
    display: inline-block;
    margin-bottom: 14px;
    color: var(--muted);
    text-decoration: none;
}

.panel {
    margin-bottom: 20px;
    padding: clamp(22px, 5vw, 42px);
    border: 1px solid var(--line);
    border-radius: 28px;
    background: var(--panel);
    box-shadow: var(--shadow);
}

.file-picker {
    display: grid;
    place-items: center;
    min-height: 130px;
    margin: 24px 0;
    border: 2px dashed #afbdd3;
    border-radius: 22px;
    background: #f8faff;
    cursor: pointer;
    font-size: 1.15rem;
    font-weight: 800;
}

.file-picker input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.file-list {
    display: grid;
    gap: 12px;
    margin: 18px 0;
}

.file-list.empty {
    padding: 22px;
    border-radius: 16px;
    background: #f6f8fb;
    color: var(--muted);
    text-align: center;
}

.file-card {
    display: grid;
    grid-template-columns: 76px 1fr auto;
    gap: 14px;
    align-items: center;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 18px;
}

.thumb {
    width: 76px;
    height: 76px;
    border-radius: 13px;
    object-fit: cover;
    background: #edf1f6;
}

.file-meta {
    display: grid;
    gap: 5px;
    min-width: 0;
}

.file-meta strong {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-meta span { color: var(--muted); }

.remove-button {
    border: 0;
    background: transparent;
    color: var(--danger);
    cursor: pointer;
}

.primary-button, .secondary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 52px;
    padding: 0 22px;
    border: 0;
    border-radius: 15px;
    font: inherit;
    font-weight: 800;
    text-decoration: none;
    cursor: pointer;
}

.primary-button {
    width: 100%;
    background: var(--primary);
    color: white;
}

.primary-button:hover { background: var(--primary-dark); }
.primary-button:disabled { opacity: .45; cursor: not-allowed; }

.secondary-button {
    background: #edf2fa;
    color: var(--text);
}

.small {
    width: auto;
    min-height: 44px;
    padding: 0 16px;
}

.status-box {
    margin: 15px 0;
    padding: 14px 16px;
    border-radius: 14px;
    background: #edf2fa;
}

.status-box.success { background: #e8f6ef; color: var(--success); }
.status-box.error { background: #fff0f1; color: var(--danger); }
.hidden { display: none !important; }

.result-panel { text-align: center; }

.receive-code {
    margin: 16px 0 8px;
    font-size: clamp(3rem, 12vw, 5.2rem);
    font-weight: 900;
    letter-spacing: .12em;
    color: var(--primary);
}

.expiry { color: var(--muted); }

.code-form {
    display: grid;
    gap: 14px;
    margin-top: 24px;
}

.code-form input {
    width: 100%;
    padding: 18px;
    border: 2px solid var(--line);
    border-radius: 17px;
    outline: 0;
    text-align: center;
    font-size: 2rem;
    font-weight: 900;
    letter-spacing: .25em;
}

.code-form input:focus { border-color: var(--primary); }

.gallery-heading {
    display: flex;
    gap: 16px;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 18px;
}

.gallery-heading h2 { margin: 5px 0 0; }

.pill {
    padding: 8px 12px;
    border-radius: 999px;
    background: #edf2fa;
    color: var(--muted);
    font-size: .86rem;
}

.gallery {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
}

.photo-card {
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
}

.photo-card > a {
    display: block;
    aspect-ratio: 4 / 3;
    background: #edf1f6;
}

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

.photo-body {
    display: grid;
    gap: 7px;
    padding: 15px;
}

.photo-body strong {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.photo-body span { color: var(--muted); font-size: .9rem; }

.photo-actions {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.photo-actions > * { flex: 1; }

@media (max-width: 640px) {
    .shell { width: min(100% - 18px, 920px); padding-top: 16px; }
    .choice-grid, .gallery { grid-template-columns: 1fr; }
    .choice-card { min-height: 190px; padding: 24px; }
    .panel { border-radius: 22px; }
    .file-card { grid-template-columns: 64px 1fr auto; }
    .thumb { width: 64px; height: 64px; }
    .gallery-heading { display: block; }
    .pill { display: inline-block; margin-top: 10px; }
}


/* Version 1.1 */
.file-picker { grid-template-rows: auto auto auto; gap: 5px; }
.file-picker.dragover { border-color: var(--primary); background: #eaf1ff; transform: scale(1.01); }
.picker-icon { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 50%; background: #e5edff; color: var(--primary); font-size: 1.7rem; }
.file-picker small { color: var(--muted); font-weight: 500; }
.qr-code { display: inline-grid; place-items: center; min-width: 230px; min-height: 230px; padding: 10px; margin: 12px auto; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.qr-code img, .qr-code canvas { max-width: 210px; height: auto; }
.receive-url { overflow-wrap: anywhere; color: var(--muted); font-size: .86rem; }
.result-actions { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 18px; }
.primary-button.compact { width: auto; }
.bulk-actions { display: flex; align-items: center; gap: 14px; margin: 0 0 18px; padding: 14px; border-radius: 16px; background: #f6f8fb; }
.bulk-note { color: var(--muted); font-size: .85rem; line-height: 1.5; }
@media (max-width: 640px) {
    .result-actions { grid-template-columns: 1fr; }
    .bulk-actions { align-items: stretch; flex-direction: column; }
    .bulk-actions .primary-button { width: 100%; }
}


/* Version 1.2 */
.selection-summary { margin: 16px 0 8px; padding: 10px 14px; border-radius: 14px; background: #f4f7fb; color: var(--muted); font-weight: 700; }
.admin-shell { max-width: 620px; }
.admin-login { margin-top: 10vh; }
.admin-login-form { display: grid; gap: 16px; margin: 22px 0; }
.admin-login-form label { display: grid; gap: 8px; font-weight: 700; }
.admin-login-form input, .admin-settings select { width: 100%; padding: 14px; border: 1px solid var(--line); border-radius: 14px; background: #fff; font: inherit; }
.admin-layout { width: min(1180px, calc(100% - 28px)); margin: 0 auto; padding: 28px 0 60px; }
.admin-header, .admin-section-title, .transfer-top { display: flex; align-items: center; justify-content: space-between; gap: 18px; }
.admin-header h1, .admin-section-title h2 { margin: 4px 0 0; }
.admin-header-actions, .transfer-actions, .admin-photo-actions { display: flex; gap: 10px; align-items: center; }
.admin-header-actions a, .transfer-actions a, .admin-photo-actions a { text-decoration: none; }
.admin-message { margin: 18px 0; }
.admin-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin: 22px 0; }
.admin-stats > div { padding: 20px; border: 1px solid var(--line); border-radius: 20px; background: #fff; box-shadow: 0 8px 24px #0000000a; }
.admin-stats span { display: block; color: var(--muted); font-size: .9rem; }
.admin-stats strong { display: block; margin-top: 7px; font-size: 1.45rem; }
.admin-settings { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 24px; }
.admin-settings form { display: flex; gap: 12px; align-items: end; }
.admin-settings label { display: grid; gap: 7px; min-width: 180px; font-weight: 700; }
.transfer-list { display: grid; gap: 16px; margin-top: 20px; }
.transfer-card { padding: 18px; border: 1px solid var(--line); border-radius: 20px; background: #fff; }
.transfer-top > div:first-child { display: flex; align-items: center; gap: 12px; }
.transfer-code { font-size: 1.65rem; letter-spacing: .12em; }
.status-pill { padding: 7px 10px; border-radius: 999px; font-size: .78rem; font-weight: 800; }
.status-pill.active { background: #e8f8ee; color: #187442; }
.status-pill.expired { background: #f2f3f5; color: #6b7280; }
.transfer-thumbs { display: flex; gap: 8px; align-items: center; margin: 16px 0; min-height: 70px; }
.transfer-thumbs img { width: 82px; height: 66px; object-fit: cover; border-radius: 12px; border: 1px solid var(--line); background: #eef1f5; }
.transfer-thumbs span { display: grid; place-items: center; width: 82px; height: 66px; border-radius: 12px; background: #eef2f8; color: var(--muted); font-weight: 800; }
.transfer-meta { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; margin: 0; }
.transfer-meta div { padding: 10px; border-radius: 12px; background: #f7f9fc; }
.transfer-meta dt { color: var(--muted); font-size: .78rem; }
.transfer-meta dd { margin: 5px 0 0; font-size: .9rem; font-weight: 700; }
.danger-button { padding: 11px 15px; border: 0; border-radius: 12px; background: #fff0f0; color: #b42318; font: inherit; font-weight: 800; cursor: pointer; }
.admin-photo-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 20px; }
.admin-photo-card { display: grid; gap: 9px; padding: 12px; border: 1px solid var(--line); border-radius: 18px; overflow: hidden; }
.admin-photo-card > a { display: block; aspect-ratio: 4 / 3; border-radius: 12px; overflow: hidden; background: #eef1f5; }
.admin-photo-card img { width: 100%; height: 100%; object-fit: cover; }
.admin-photo-card strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.admin-photo-card span { color: var(--muted); font-size: .85rem; }
.admin-photo-actions > * { flex: 1; }
.admin-photo-actions form { display: flex; }
.admin-photo-actions form button { width: 100%; }
.empty-admin { padding: 30px; text-align: center; color: var(--muted); }
@media (max-width: 820px) {
    .admin-stats { grid-template-columns: repeat(2, 1fr); }
    .admin-settings { grid-template-columns: 1fr; }
    .admin-settings form { align-items: stretch; flex-direction: column; }
    .admin-photo-grid { grid-template-columns: repeat(2, 1fr); }
    .transfer-meta { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
    .admin-layout { width: min(100% - 16px, 1180px); padding-top: 14px; }
    .admin-header, .admin-section-title, .transfer-top { align-items: stretch; flex-direction: column; }
    .admin-header-actions, .transfer-actions { width: 100%; }
    .admin-header-actions > *, .transfer-actions > * { flex: 1; text-align: center; }
    .admin-stats { grid-template-columns: 1fr 1fr; gap: 8px; }
    .admin-stats > div { padding: 14px; }
    .admin-photo-grid { grid-template-columns: 1fr 1fr; gap: 9px; }
    .transfer-thumbs img, .transfer-thumbs span { width: 60px; height: 52px; }
    .transfer-meta { grid-template-columns: 1fr; }
}


.admin-two-column { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin: 18px 0; }
.admin-account, .admin-system { margin: 0; }
.admin-password-form { display: grid; gap: 12px; margin-top: 18px; }
.admin-password-form label { display: grid; gap: 7px; font-weight: 700; }
.admin-password-form input { width: 100%; padding: 13px 14px; border: 1px solid var(--line); border-radius: 14px; background: #fff; font: inherit; }
.system-info-list { display: grid; gap: 0; margin: 18px 0 0; }
.system-info-list > div { display: grid; grid-template-columns: minmax(150px, .9fr) 1.4fr; gap: 16px; padding: 11px 0; border-bottom: 1px solid var(--line); }
.system-info-list > div:last-child { border-bottom: 0; }
.system-info-list dt { color: var(--muted); }
.system-info-list dd { margin: 0; font-weight: 700; overflow-wrap: anywhere; }

@media (max-width: 820px) {
    .admin-two-column { grid-template-columns: 1fr; }
}
@media (max-width: 520px) {
    .system-info-list > div { grid-template-columns: 1fr; gap: 3px; }
}

/* v1.4 performance UI */
.admin-list-count{margin:.35rem 0 0;color:var(--muted,#687083);font-size:.9rem}
.admin-pagination{display:flex;justify-content:center;align-items:center;gap:16px;margin-top:24px;flex-wrap:wrap}
.admin-pagination a{display:inline-flex;align-items:center;justify-content:center;min-width:92px;padding:10px 16px;border:1px solid #d8ddea;border-radius:12px;background:#fff;color:inherit;text-decoration:none;font-weight:700}
.admin-pagination span{font-weight:700;color:#687083}
.transfer-thumbs img,.admin-photo-card img{content-visibility:auto}

/* Version 1.5 send / receive polish */
.selection-summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 40px;
    padding: 9px 13px;
    border-radius: 12px;
    background: #f6f8fb;
    color: var(--muted);
    font-weight: 700;
}
.file-picker.is-busy {
    opacity: .62;
    cursor: wait;
    pointer-events: none;
}
.progress-panel {
    margin: 16px 0;
    padding: 16px;
    border: 1px solid #cdd9ee;
    border-radius: 16px;
    background: #f7faff;
}
.progress-heading {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 10px;
}
.progress-heading span {
    color: var(--primary);
    font-weight: 900;
}
.progress-track {
    overflow: hidden;
    height: 12px;
    border-radius: 999px;
    background: #e0e8f5;
}
.progress-bar {
    width: 0;
    height: 100%;
    border-radius: inherit;
    background: var(--primary);
    transition: width .18s ease;
}
.progress-detail {
    margin-top: 9px;
    color: var(--muted);
    font-size: .9rem;
    overflow-wrap: anywhere;
}
.text-button {
    margin-top: 16px;
    padding: 8px 12px;
    border: 0;
    background: transparent;
    color: var(--primary);
    font: inherit;
    font-weight: 800;
    cursor: pointer;
}
.status-box.info { background: #edf2fa; color: #304665; }
.status-box { overflow-wrap: anywhere; }
.skeleton-card { pointer-events: none; }
.skeleton-image,
.skeleton-line {
    position: relative;
    overflow: hidden;
    background: #e8edf4;
}
.skeleton-image { aspect-ratio: 4 / 3; }
.skeleton-line { height: 13px; border-radius: 7px; }
.skeleton-line.wide { width: 88%; height: 16px; }
.skeleton-line.button { width: 100%; height: 43px; margin-top: 7px; border-radius: 13px; }
.skeleton-image::after,
.skeleton-line::after {
    content: "";
    position: absolute;
    inset: 0;
    transform: translateX(-100%);
    background: linear-gradient(90deg, transparent, rgba(255,255,255,.75), transparent);
    animation: skeleton-shimmer 1.25s infinite;
}
@keyframes skeleton-shimmer { to { transform: translateX(100%); } }
.photo-card img { display: block; }
.photo-card > a { overflow: hidden; }
.photo-card > a:focus-visible,
.primary-button:focus-visible,
.secondary-button:focus-visible,
.text-button:focus-visible,
.remove-button:focus-visible,
.file-picker:focus-visible {
    outline: 3px solid rgba(39, 100, 231, .28);
    outline-offset: 3px;
}
@media (max-width: 640px) {
    .file-picker { min-height: 118px; margin: 18px 0; }
    .selection-summary { font-size: .92rem; }
    .file-card { gap: 10px; padding: 10px; }
    .remove-button { padding: 12px 4px; }
    .photo-actions { flex-direction: column; }
    .photo-actions > * { width: 100%; }
    .receive-code { letter-spacing: .08em; }
}
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}


/* Version 1.6 compact mobile top screen */
@media (max-width: 640px) {
    .shell { padding: 8px 0 24px; }
    .hero { padding: 18px 8px 14px; }
    .hero h1 { margin-bottom: 5px; font-size: clamp(2rem, 11vw, 2.75rem); }
    .hero p { margin: 6px 0; line-height: 1.45; }
    .choice-grid { gap: 10px; }
    .choice-card {
        display: grid;
        grid-template-columns: 50px minmax(0, 1fr);
        grid-template-rows: auto auto;
        column-gap: 13px;
        row-gap: 2px;
        align-items: center;
        min-height: 0;
        padding: 15px 17px;
        border-radius: 20px;
    }
    .choice-icon {
        grid-column: 1;
        grid-row: 1 / span 2;
        width: 50px;
        height: 50px;
        border-radius: 15px;
        font-size: 1.65rem;
    }
    .choice-card h2 {
        grid-column: 2;
        grid-row: 1;
        margin: 0;
        font-size: 1.35rem;
        line-height: 1.25;
    }
    .choice-card p {
        grid-column: 2;
        grid-row: 2;
        margin: 0;
        font-size: .86rem;
        line-height: 1.35;
    }
    .note { margin-top: 13px; font-size: .82rem; line-height: 1.45; }
}