:root {
    --bt-blue: #0864e8;
    --bt-blue-dark: #064bb3;
    --bt-ink: #0b2447;
    --bt-muted: #52627a;
    --bt-line: #dbe3ee;
    --bt-soft: #f4f8fd;
    --bt-white: #fff;
    --bt-shadow: 0 12px 34px rgba(25, 58, 98, .10);
}

.sr-only { 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; }
.bt-page { background: radial-gradient(circle at 50% 0, #edf5ff 0, #f8fbff 34%, #fff 72%); color: var(--bt-ink); min-height: 70vh; padding: 0 0 64px; }
.bt-page *, .bt-page *::before, .bt-page *::after { box-sizing: border-box; }
.bt-page [hidden] { display: none !important; }
.bt-shell { width: min(1140px, calc(100% - 32px)); margin: 0 auto; }
.bt-breadcrumb { display: flex; align-items: center; flex-wrap: wrap; gap: 9px; padding: 20px 0 6px; color: #61718a; font-size: 14px; }
.bt-breadcrumb a { color: var(--bt-blue); text-decoration: none; }
.bt-breadcrumb a:hover { text-decoration: underline; }
.bt-hero, .bt-tool-hero { max-width: 900px; margin: 0 auto; padding: 46px 0 32px; text-align: center; }
.bt-eyebrow { display: inline-flex; align-items: center; gap: 8px; color: var(--bt-blue); font-size: 13px; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.bt-hero h1, .bt-tool-hero h1 { margin: 12px auto 10px; color: var(--bt-ink); font-size: clamp(32px, 5vw, 52px); line-height: 1.08; letter-spacing: -.04em; }
.bt-tool-hero h1 { font-size: clamp(32px, 4vw, 46px); }
.bt-hero > p, .bt-tool-hero > p { max-width: 780px; margin: 0 auto; color: var(--bt-muted); font-size: clamp(16px, 2vw, 19px); line-height: 1.65; }
.bt-search-wrap { max-width: 680px; margin: 28px auto 0; text-align: left; }
.bt-search-wrap label { display: block; margin-bottom: 8px; font-size: 14px; font-weight: 800; }
.bt-search { position: relative; }
.bt-search i { position: absolute; top: 50%; left: 18px; color: #8290a5; transform: translateY(-50%); }
.bt-search input { width: 100%; height: 58px; padding: 0 18px 0 50px; border: 1px solid #cbd7e7; border-radius: 15px; background: #fff; color: var(--bt-ink); font-size: 16px; box-shadow: 0 9px 26px rgba(25, 58, 98, .08); }
.bt-search input:focus { border-color: var(--bt-blue); outline: 3px solid rgba(8,100,232,.16); }
.bt-section, .bt-content-panel, .bt-faq, .bt-related, .bt-steps, .bt-article { margin-top: 28px; }
.bt-section-head { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 17px; }
.bt-section-head span { color: var(--bt-blue); font-size: 12px; font-weight: 850; letter-spacing: .08em; text-transform: uppercase; }
.bt-section-head h2, .bt-content-panel h2, .bt-faq h2, .bt-related h2, .bt-steps h2, .bt-article h2 { margin: 4px 0 0; color: var(--bt-ink); font-size: clamp(23px, 3vw, 31px); letter-spacing: -.025em; }
.bt-section-head p { margin: 0; color: var(--bt-muted); font-size: 14px; }
.bt-filters { display: flex; flex-wrap: wrap; gap: 9px; margin: 0 0 18px; }
.bt-filters button { min-height: 42px; padding: 0 17px; border: 1px solid #cad6e5; border-radius: 999px; background: #fff; color: #34445d; font-weight: 750; cursor: pointer; }
.bt-filters button:hover, .bt-filters button.is-active { border-color: var(--bt-blue); background: #eaf3ff; color: var(--bt-blue-dark); }
.bt-filters button:focus-visible, .bt-tool-card:focus-visible, .bt-primary-button:focus-visible, .bt-secondary-button:focus-visible, .bt-text-button:focus-visible, .bt-dropzone:focus-visible { outline: 3px solid rgba(8,100,232,.25); outline-offset: 3px; }
.bt-tool-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.bt-tool-card { display: flex; gap: 17px; min-height: 172px; padding: 22px; border: 1px solid var(--bt-line); border-radius: 17px; background: #fff; color: var(--bt-ink); text-decoration: none; box-shadow: 0 7px 20px rgba(25,58,98,.06); transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease; }
.bt-tool-card:hover { border-color: #9bc3fb; box-shadow: var(--bt-shadow); transform: translateY(-3px); }
.bt-tool-card[hidden] { display: none; }
.bt-tool-icon { display: grid; place-items: center; flex: 0 0 54px; width: 54px; height: 54px; border-radius: 15px; background: linear-gradient(145deg, #e8f2ff, #f5f9ff); color: var(--bt-blue); font-size: 24px; }
.bt-tool-copy { display: flex; flex: 1; min-width: 0; flex-direction: column; }
.bt-tool-copy strong { font-size: 18px; line-height: 1.3; }
.bt-tool-copy > span { margin-top: 8px; color: var(--bt-muted); font-size: 14px; line-height: 1.55; }
.bt-tool-copy .bt-tool-link { display: inline-flex; align-items: center; gap: 8px; margin-top: auto; padding-top: 14px; color: var(--bt-blue); font-weight: 800; }
.bt-empty { padding: 24px; border: 1px dashed #bdc9d9; border-radius: 14px; color: var(--bt-muted); text-align: center; }
.bt-content-panel, .bt-article { padding: clamp(24px, 4vw, 42px); border: 1px solid var(--bt-line); border-radius: 20px; background: #fff; box-shadow: 0 8px 28px rgba(25,58,98,.06); }
.bt-copy-grid, .bt-comparison { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 24px; }
.bt-copy-grid h3, .bt-comparison h3, .bt-article h3 { margin: 0 0 8px; font-size: 18px; }
.bt-copy-grid p, .bt-comparison p, .bt-article p { margin: 0; color: var(--bt-muted); line-height: 1.7; }
.bt-faq { max-width: 900px; margin-right: auto; margin-left: auto; }
.bt-faq h2 { margin-bottom: 16px; text-align: center; }
.bt-faq details { border-bottom: 1px solid var(--bt-line); background: #fff; }
.bt-faq summary { position: relative; padding: 20px 42px 20px 5px; color: var(--bt-ink); font-weight: 800; cursor: pointer; list-style: none; }
.bt-faq summary::-webkit-details-marker { display: none; }
.bt-faq summary::after { content: "+"; position: absolute; top: 16px; right: 8px; color: var(--bt-blue); font-size: 24px; }
.bt-faq details[open] summary::after { content: "−"; }
.bt-faq details p { margin: 0; padding: 0 44px 20px 5px; color: var(--bt-muted); line-height: 1.7; }
.bt-all-tools-link { display: inline-flex; align-items: center; gap: 8px; margin-top: 16px; color: var(--bt-blue); font-weight: 850; text-decoration: none; }

.bt-converter { padding: clamp(18px, 4vw, 40px); border: 1px solid #d4deeb; border-radius: 19px; background: rgba(255,255,255,.96); box-shadow: var(--bt-shadow); }
.bt-dropzone { display: flex; min-height: 270px; align-items: center; justify-content: center; flex-direction: column; gap: 12px; padding: 28px; border: 2px dashed var(--bt-blue); border-radius: 18px; background: linear-gradient(145deg, #fbfdff, #f1f7ff); text-align: center; cursor: pointer; transition: border-color .2s, background .2s; }
.bt-dropzone.is-dragging { border-color: #0346a7; background: #e7f2ff; }
.bt-dropzone > strong { color: #35465f; font-size: 17px; }
.bt-dropzone > span { color: #718097; font-size: 14px; }
.bt-format-flow { display: flex; align-items: center; gap: 20px; color: var(--bt-blue); font-size: 28px; }
.bt-format-icon { display: grid; place-items: end center; width: 70px; height: 82px; padding-bottom: 9px; border: 2px solid #aeb9c8; border-radius: 10px 10px 4px 4px; background: #fff; font-size: 15px; font-weight: 950; box-shadow: 0 5px 13px rgba(25,58,98,.12); }
.bt-format-icon.bt-webp { color: #128353; }
.bt-format-icon.bt-jpg { color: #0b54c4; }
.bt-primary-button, .bt-secondary-button, .bt-text-button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; gap: 9px; border-radius: 10px; font-size: 15px; font-weight: 850; cursor: pointer; }
.bt-primary-button { padding: 0 22px; border: 1px solid var(--bt-blue); background: linear-gradient(180deg, #1675f7, #075bd8); color: #fff; box-shadow: 0 7px 16px rgba(8,100,232,.24); }
.bt-primary-button:hover { background: var(--bt-blue-dark); }
.bt-primary-button:disabled { border-color: #cad2de; background: #e4e8ee; color: #8492a6; box-shadow: none; cursor: not-allowed; }
.bt-secondary-button { padding: 0 20px; border: 1px solid #a8c9f7; background: #eaf3ff; color: #064eb8; }
.bt-text-button { padding: 0 12px; border: 0; background: transparent; color: #53637a; }
.bt-text-button:disabled { color: #a8b0bc; cursor: not-allowed; }
.bt-wide { flex: 1; }
.bt-privacy-note, .bt-transparency-note { display: flex; align-items: flex-start; gap: 10px; margin: 14px 0 0; padding: 13px 15px; border-radius: 11px; color: #315277; font-size: 14px; line-height: 1.5; }
.bt-privacy-note { background: #edf7ff; }
.bt-transparency-note { background: #fff8e8; color: #6f541c; }
.bt-converter-controls { display: grid; grid-template-columns: 2fr 1fr; gap: 18px; margin-top: 20px; }
.bt-converter.has-files .bt-dropzone, .bt-converter.has-files .bt-privacy-note, .bt-converter.has-files .bt-transparency-note { display: none; }
.bt-settings-summary { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 18px; margin-bottom: 20px; padding: 18px 22px; border: 1px solid #ced9e7; border-radius: 16px; background: #fff; box-shadow: 0 5px 16px rgba(25,58,98,.05); }
.bt-settings-summary[hidden] { display: none; }
.bt-settings-icon { display: grid; place-items: center; width: 48px; height: 48px; border-radius: 50%; background: #e9f3ff; color: var(--bt-blue); font-size: 20px; }
.bt-settings-summary strong { overflow: hidden; color: var(--bt-ink); font-size: clamp(15px, 2vw, 19px); text-overflow: ellipsis; white-space: nowrap; }
.bt-settings-summary button { min-height: 42px; padding: 0 4px; border: 0; background: transparent; color: var(--bt-blue); font-size: 16px; font-weight: 900; cursor: pointer; }
.bt-settings-summary button:focus-visible { border-radius: 7px; outline: 3px solid rgba(8,100,232,.22); outline-offset: 3px; }
.bt-settings-summary + .bt-converter-controls { margin-top: 0; margin-bottom: 20px; }
.bt-settings-summary + .bt-converter-controls[hidden] { display: none; }
.bt-control-group { padding: 16px; border: 1px solid var(--bt-line); border-radius: 12px; background: #fff; }
.bt-control-group label { display: flex; justify-content: space-between; margin-bottom: 12px; color: var(--bt-ink); font-size: 14px; font-weight: 800; }
.bt-control-group input[type="range"] { width: 100%; accent-color: var(--bt-blue); }
.bt-color-control { display: flex; align-items: center; gap: 12px; }
.bt-color-control input { width: 52px; height: 38px; padding: 2px; border: 1px solid #cbd6e5; border-radius: 8px; background: #fff; }
.bt-color-control span { font-family: ui-monospace, SFMono-Regular, Consolas, monospace; color: #4a5a70; }
.bt-file-list { display: grid; gap: 11px; margin-top: 18px; }
.bt-file-list:not(:empty) { padding: 20px; border: 1px solid #ced9e7; border-radius: 17px; background: #fff; box-shadow: 0 5px 16px rgba(25,58,98,.04); }
.bt-selected-header { display: flex; align-items: center; justify-content: space-between; gap: 14px; margin-bottom: 5px; }
.bt-selected-header h3 { margin: 0; color: var(--bt-ink); font-size: clamp(18px, 2.5vw, 24px); }
.bt-selected-header h3 i { margin-left: 7px; color: #079548; }
.bt-selected-header > span { padding: 8px 12px; border-radius: 10px; background: #e5f8ea; color: #07843e; font-size: 13px; font-weight: 900; }
.bt-file-item { display: grid; grid-template-columns: 72px minmax(0, 1fr) auto; align-items: center; gap: 14px; padding: 12px; border: 1px solid var(--bt-line); border-radius: 13px; background: #fff; }
.bt-file-preview { width: 72px; height: 72px; border-radius: 9px; background: #edf1f6; object-fit: cover; }
.bt-file-meta { min-width: 0; }
.bt-file-meta strong { display: block; overflow: hidden; color: var(--bt-ink); text-overflow: ellipsis; white-space: nowrap; }
.bt-file-meta span { display: block; margin-top: 5px; color: var(--bt-muted); font-size: 13px; }
.bt-file-actions { display: flex; align-items: center; gap: 8px; }
.bt-file-actions button, .bt-file-actions a { display: inline-flex; min-height: 38px; align-items: center; justify-content: center; gap: 7px; padding: 0 12px; border: 1px solid #ccd7e5; border-radius: 8px; background: #fff; color: #34445b; font-size: 13px; font-weight: 800; text-decoration: none; cursor: pointer; }
.bt-file-actions a { border-color: #9fc5f7; background: #eaf3ff; color: #0758cb; }
.bt-file-actions button:hover { border-color: #e3a7a7; color: #b42318; }
.bt-add-more { justify-self: center; padding: 9px 12px; border: 0; background: transparent; color: var(--bt-blue); font-size: 13px; font-weight: 850; cursor: pointer; }
.bt-add-more:focus-visible { border-radius: 8px; outline: 3px solid rgba(8,100,232,.22); outline-offset: 2px; }
.bt-status { min-height: 24px; margin-top: 14px; color: #35506f; font-size: 14px; font-weight: 700; }
.bt-status.is-error { color: #b42318; }
.bt-status.is-success { color: #087443; }
.bt-action-row { display: flex; align-items: center; gap: 10px; margin-top: 12px; }
.bt-converter.has-files .bt-action-row .bt-text-button { display: none; }
.bt-result-panel { max-width: 820px; margin: 28px auto 0; padding: clamp(28px, 5vw, 54px); scroll-margin-top: 92px; border: 2px solid #0a9b45; border-radius: 22px; background: radial-gradient(circle at 50% 30%, #fff 0, #f5fff7 42%, #edfbf1 100%); text-align: center; box-shadow: 0 12px 30px rgba(6,130,57,.09); }
.bt-result-panel[hidden] { display: none; }
.bt-result-panel:focus { outline: none; }
.bt-result-celebration { position: relative; width: 112px; height: 100px; margin: 0 auto 4px; }
.bt-result-check { position: absolute; top: 0; left: 50%; display: grid; place-items: center; width: 76px; height: 76px; border-radius: 50%; background: linear-gradient(145deg, #13b758, #058837); color: #fff; font-size: 37px; box-shadow: 0 12px 24px rgba(7,143,61,.2); transform: translateX(-50%); }
.bt-result-spark { position: absolute; color: #32b945; font-size: 24px; }
.bt-result-spark-one { top: 10px; left: 0; }
.bt-result-spark-two { top: 28px; right: 0; color: #059848; }
.bt-result-panel h2 { margin: 0; color: #07883f; font-size: clamp(28px, 4vw, 42px); letter-spacing: -.035em; }
.bt-result-subtitle { margin: 12px 0 24px; color: var(--bt-muted); font-size: clamp(17px, 2.4vw, 22px); }
.bt-result-flow { display: flex; max-width: 570px; min-height: 130px; align-items: center; justify-content: center; gap: clamp(30px, 7vw, 70px); margin: 0 auto; padding: 20px; border: 1px solid #d6dfeb; border-radius: 18px; background: #fff; color: #5f6f86; font-size: 30px; box-shadow: 0 5px 18px rgba(25,58,98,.04); }
.bt-result-format { position: relative; display: grid; place-items: center; width: 76px; height: 86px; }
.bt-result-format i { color: #aab6c5; font-size: 68px; }
.bt-result-format strong { position: absolute; bottom: 9px; font-size: 15px; }
.bt-result-webp strong { color: #078b42; }
.bt-result-jpg strong { color: #075bd8; }
.bt-result-sizes { margin: 16px 0 24px; color: var(--bt-ink); font-size: clamp(18px, 3vw, 25px); }
.bt-result-primary, .bt-result-new, .bt-result-remove { display: flex; width: 100%; min-height: 62px; align-items: center; justify-content: center; gap: 13px; border-radius: 13px; font-size: clamp(17px, 2.5vw, 22px); font-weight: 900; text-decoration: none; cursor: pointer; }
.bt-result-primary { border: 1px solid var(--bt-blue); background: linear-gradient(135deg, #0b56ca, #0767ec); color: #fff; box-shadow: 0 10px 20px rgba(8,100,232,.2); }
.bt-result-primary:hover { background: var(--bt-blue-dark); color: #fff; }
.bt-result-new { min-height: 52px; margin-top: 15px; border: 2px solid var(--bt-blue); background: #fff; color: #075bd8; font-size: 16px; }
.bt-result-remove { min-height: 42px; margin-top: 13px; border: 0; background: transparent; color: #5c6c81; font-size: 15px; font-weight: 700; }
.bt-result-primary:focus-visible, .bt-result-new:focus-visible, .bt-result-remove:focus-visible { outline: 3px solid rgba(8,100,232,.25); outline-offset: 3px; }
.bt-result-files { display: grid; gap: 8px; margin-top: 16px; text-align: left; }
.bt-result-files a { display: flex; min-height: 46px; align-items: center; justify-content: space-between; gap: 15px; padding: 9px 13px; border: 1px solid #cfe0f5; border-radius: 10px; background: #fff; color: #0758cb; font-weight: 800; text-decoration: none; }
.bt-result-files span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.bt-result-files small { flex: 0 0 auto; color: var(--bt-muted); }
.bt-trust-strip { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 14px; border: 1px solid var(--bt-line); border-radius: 13px; background: #fff; box-shadow: 0 5px 16px rgba(25,58,98,.06); }
.bt-trust-strip span { display: flex; min-height: 56px; align-items: center; justify-content: center; gap: 10px; color: #233b5c; font-weight: 750; }
.bt-trust-strip span + span { border-left: 1px solid var(--bt-line); }
.bt-trust-strip i { color: var(--bt-blue); }
.bt-steps h2 { text-align: center; }
.bt-step-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 13px; margin-top: 16px; }
.bt-step-grid article { display: flex; gap: 14px; padding: 20px; border: 1px solid var(--bt-line); border-radius: 14px; background: #fff; box-shadow: 0 5px 16px rgba(25,58,98,.05); }
.bt-step-grid article > span { display: grid; place-items: center; flex: 0 0 40px; width: 40px; height: 40px; border-radius: 50%; background: #e7f1ff; color: var(--bt-blue); font-size: 20px; font-weight: 900; }
.bt-step-grid h3 { margin: 1px 0 6px; font-size: 16px; }
.bt-step-grid p { margin: 0; color: var(--bt-muted); font-size: 13px; line-height: 1.55; }
.bt-article { display: grid; gap: 28px; }
.bt-comparison { grid-template-columns: 1fr 1fr; }
.bt-comparison > div { padding: 18px; border: 1px solid var(--bt-line); border-radius: 12px; background: var(--bt-soft); }

@media (max-width: 760px) {
    .bt-shell { width: min(100% - 20px, 1140px); }
    .bt-breadcrumb { padding-top: 14px; }
    .bt-hero, .bt-tool-hero { padding: 32px 5px 24px; }
    .bt-tool-grid, .bt-copy-grid, .bt-step-grid, .bt-comparison { grid-template-columns: 1fr; }
    .bt-section-head { align-items: flex-start; flex-direction: column; gap: 6px; }
    .bt-converter { padding: 13px; }
    .bt-dropzone { min-height: 240px; padding: 22px 12px; }
    .bt-settings-summary { gap: 10px; margin-bottom: 14px; padding: 13px; border-radius: 14px; }
    .bt-settings-icon { width: 42px; height: 42px; font-size: 17px; }
    .bt-settings-summary strong { font-size: 14px; }
    .bt-settings-summary button { font-size: 14px; }
    .bt-converter-controls { grid-template-columns: 1fr; }
    .bt-file-list:not(:empty) { padding: 14px; }
    .bt-selected-header { align-items: flex-start; }
    .bt-selected-header h3 { font-size: 19px; }
    .bt-selected-header > span { padding: 6px 9px; }
    .bt-file-item { grid-template-columns: 58px minmax(0, 1fr); }
    .bt-file-preview { width: 58px; height: 58px; }
    .bt-file-actions { grid-column: 1 / -1; justify-content: flex-end; }
    .bt-action-row { align-items: stretch; flex-direction: column; }
    .bt-result-panel { margin-top: 22px; padding: 30px 18px; scroll-margin-top: 76px; border-radius: 18px; }
    .bt-result-celebration { height: 86px; }
    .bt-result-check { width: 68px; height: 68px; font-size: 32px; }
    .bt-result-flow { min-height: 112px; gap: 30px; padding: 16px; }
    .bt-result-primary { min-height: 58px; }
    .bt-trust-strip { grid-template-columns: repeat(3, 1fr); }
    .bt-trust-strip span { min-width: 0; min-height: 82px; flex-direction: column; gap: 7px; padding: 9px 5px; text-align: center; font-size: 12px; }
    .bt-trust-strip span + span { border-top: 0; border-left: 1px solid var(--bt-line); }
}

@media (max-width: 420px) {
    .bt-tool-card { min-height: 0; padding: 17px; }
    .bt-tool-icon { flex-basis: 46px; width: 46px; height: 46px; }
    .bt-primary-button { width: 100%; padding: 0 12px; }
    .bt-format-flow { gap: 13px; }
    .bt-settings-summary { grid-template-columns: auto minmax(0, 1fr); }
    .bt-settings-summary button { grid-column: 2; justify-self: start; min-height: 28px; margin-top: -8px; }
    .bt-result-panel { padding-right: 14px; padding-left: 14px; }
    .bt-result-flow { gap: 22px; }
}

@media (prefers-reduced-motion: reduce) {
    .bt-tool-card { transition: none; }
    .bt-result-panel { scroll-behavior: auto; }
}