:root {
    color-scheme: light;
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --page: #f2f0eb;
    --panel: #ffffff;
    --text: #1f2527;
    --muted: #697174;
    --border: #d8dcda;
    --border-strong: #aeb6b3;
    --accent: #1d6257;
    --accent-hover: #154d45;
    --accent-soft: #e7f1ef;
    --danger: #9b2c2c;
    --disabled-bg: #eceeed;
    --disabled-border: #c9cecb;
    --disabled-text: #858d89;
    --shadow: 0 18px 50px rgba(31, 37, 39, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-width: 320px;
    min-height: 100vh;
    background: var(--page);
    color: var(--text);
}

button,
select,
input {
    font: inherit;
}

button,
select,
a {
    -webkit-tap-highlight-color: transparent;
}

.app-shell {
    width: min(1080px, calc(100% - 32px));
    margin: 0 auto;
    padding: 56px 0 72px;
}

.site-header {
    margin-bottom: 24px;
}

.eyebrow {
    margin: 0 0 8px;
    color: var(--accent);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

h1,
h2,
h3,
p {
    margin-top: 0;
}

h1 {
    margin-bottom: 8px;
    font-size: clamp(2rem, 5vw, 3.5rem);
    line-height: 1;
    letter-spacing: -0.045em;
}

.intro {
    max-width: 700px;
    margin-bottom: 0;
    color: var(--muted);
    font-size: 1rem;
    line-height: 1.6;
}

.converter-panel {
    padding: clamp(20px, 4vw, 36px);
    border: 1px solid var(--border);
    border-radius: 20px;
    background: var(--panel);
    box-shadow: var(--shadow);
}

.format-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    gap: 18px;
    align-items: end;
}

.format-control {
    display: grid;
    gap: 8px;
    color: var(--muted);
    font-size: 0.85rem;
    font-weight: 700;
}

.format-control select {
    width: 100%;
    min-height: 48px;
    padding: 0 42px 0 14px;
    border: 1px solid var(--border-strong);
    border-radius: 10px;
    background: #fff;
    color: var(--text);
    cursor: pointer;
}

.format-control select:focus-visible,
.drop-zone:focus-visible,
button:focus-visible,
a:focus-visible {
    outline: 3px solid rgba(29, 98, 87, 0.25);
    outline-offset: 2px;
}

.format-arrow {
    display: grid;
    width: 42px;
    height: 48px;
    place-items: center;
    color: var(--accent);
    font-size: 1.6rem;
    font-weight: 800;
}

.drop-zone {
    display: flex;
    min-height: 210px;
    margin-top: 28px;
    padding: 28px;
    border: 2px dashed var(--border-strong);
    border-radius: 14px;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background: #fafaf8;
    text-align: center;
    cursor: pointer;
    transition: border-color 120ms ease, background 120ms ease, transform 120ms ease;
}

.drop-zone:hover,
.drop-zone.is-dragging {
    border-color: var(--accent);
    background: var(--accent-soft);
}

.drop-zone.is-dragging {
    transform: scale(1.005);
}

.drop-zone strong {
    font-size: 1.05rem;
}

.drop-zone span {
    color: var(--muted);
    font-size: 0.9rem;
}

.primary-button,
.secondary-button,
.download-link {
    display: inline-flex;
    min-height: 44px;
    padding: 0 18px;
    border-radius: 9px;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    text-decoration: none;
    cursor: pointer;
}

.primary-button {
    border: 1px solid var(--accent);
    background: var(--accent);
    color: #fff;
}

.primary-button:hover {
    border-color: var(--accent-hover);
    background: var(--accent-hover);
}

.primary-button:disabled {
    opacity: 0.55;
    cursor: not-allowed;
}

.secondary-button {
    border: 1px solid var(--border-strong);
    background: #fff;
    color: var(--text);
}

.secondary-button:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.download-link {
    border: 1px solid var(--accent);
    background: #fff;
    color: var(--accent);
}

.download-link.is-disabled,
.download-link[aria-disabled="true"] {
    border-color: var(--disabled-border);
    background: var(--disabled-bg);
    color: var(--disabled-text);
    cursor: not-allowed;
    pointer-events: none;
}

.status {
    min-height: 24px;
    margin: 18px 0 0;
    color: var(--muted);
    font-size: 0.9rem;
}

.status.is-error {
    color: var(--danger);
    font-weight: 700;
}

.status.is-success {
    color: var(--accent);
    font-weight: 700;
}

.file-details {
    display: grid;
    grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr);
    gap: 20px;
    margin-top: 24px;
}

.preview-card,
.details-card {
    min-width: 0;
    border: 1px solid var(--border);
    border-radius: 14px;
    overflow: hidden;
    background: #fff;
}

.section-heading {
    padding: 14px 16px;
    border-bottom: 1px solid var(--border);
    background: #fafaf8;
}

.section-heading h3 {
    margin: 0;
    font-size: 0.95rem;
}

.preview-stage {
    display: grid;
    min-height: 360px;
    padding: 20px;
    place-items: center;
    overflow: auto;
    background-color: #efefec;
    background-image:
        linear-gradient(45deg, #dadbd7 25%, transparent 25%),
        linear-gradient(-45deg, #dadbd7 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #dadbd7 75%),
        linear-gradient(-45deg, transparent 75%, #dadbd7 75%);
    background-position: 0 0, 0 8px, 8px -8px, -8px 0;
    background-size: 16px 16px;
}

#preview-canvas {
    display: block;
    max-width: 100%;
    height: auto;
    image-rendering: auto;
    background: #fff;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.12);
}

.metadata {
    margin: 0;
    padding: 4px 16px 8px;
}

.metadata > div {
    display: grid;
    grid-template-columns: minmax(100px, 0.8fr) minmax(0, 1.2fr);
    gap: 14px;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.metadata > div:last-child {
    border-bottom: 0;
}

.metadata dt {
    color: var(--muted);
    font-size: 0.82rem;
    font-weight: 700;
}

.metadata dd {
    min-width: 0;
    margin: 0;
    overflow-wrap: anywhere;
    font-size: 0.88rem;
    font-weight: 650;
    text-align: right;
}

.actions {
    display: flex;
    padding: 16px;
    border-top: 1px solid var(--border);
    gap: 10px;
    flex-wrap: wrap;
}

.visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}

@media (max-width: 760px) {
    .app-shell {
        width: min(100% - 20px, 1080px);
        padding-top: 28px;
    }

    .converter-panel {
        border-radius: 14px;
    }

    .format-row {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .format-arrow {
        width: 100%;
        height: 24px;
        transform: rotate(90deg);
    }

    .file-details {
        grid-template-columns: 1fr;
    }

    .preview-stage {
        min-height: 260px;
    }
}

.section-heading-inline {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 12px;
}

.heading-note {
    min-width: 0;
    overflow: hidden;
    color: var(--muted);
    font-size: 0.78rem;
    font-weight: 650;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-list-card {
    grid-column: 1 / -1;
    min-width: 0;
    border: 1px solid var(--border);
    border-radius: 14px;
    overflow: hidden;
    background: #fff;
}

.file-list {
    max-height: 360px;
    overflow: auto;
}

.file-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: stretch;
    border-bottom: 1px solid var(--border);
    background: #fff;
}

.file-row:last-child {
    border-bottom: 0;
}

.file-row.is-selected {
    background: var(--accent-soft);
}

.file-row.has-error {
    background: #fff8f8;
}

.file-row-main {
    display: grid;
    width: 100%;
    min-width: 0;
    padding: 13px 16px;
    border: 0;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 16px;
    background: transparent;
    color: var(--text);
    text-align: left;
    cursor: pointer;
}

.file-row-main:hover:not(:disabled) {
    background: rgba(29, 98, 87, 0.06);
}

.file-row-main:disabled {
    cursor: default;
}

.file-row-text {
    display: grid;
    min-width: 0;
    gap: 3px;
}

.file-row-text strong,
.file-row-detail {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-row-text strong {
    font-size: 0.88rem;
}

.file-row-detail {
    color: var(--muted);
    font-size: 0.76rem;
}

.file-state {
    font-size: 0.76rem;
    font-weight: 800;
    white-space: nowrap;
}

.file-state-ready,
.file-state-converted {
    color: var(--accent);
}

.file-state-reading,
.file-state-converting {
    color: var(--muted);
}

.file-state-error {
    color: var(--danger);
}

.file-row-download {
    display: inline-flex;
    min-width: 132px;
    padding: 0 16px;
    border: 0;
    border-left: 1px solid var(--border);
    align-items: center;
    justify-content: center;
    background: transparent;
    color: var(--accent);
    font: inherit;
    font-size: 0.8rem;
    font-weight: 800;
    text-decoration: none;
}

.file-row-download:hover:not(:disabled) {
    background: var(--accent-soft);
}

.file-row-download:disabled,
.file-row-download.is-disabled {
    background: var(--disabled-bg);
    color: var(--disabled-text);
    cursor: not-allowed;
}

@media (max-width: 620px) {
    .section-heading-inline {
        align-items: flex-start;
        flex-direction: column;
        gap: 4px;
    }

    .heading-note {
        max-width: 100%;
    }

    .file-row-main {
        grid-template-columns: 1fr;
        gap: 6px;
    }

    .file-row-download {
        min-width: 82px;
        padding: 0 10px;
    }
}