:root { color-scheme: light dark; --bg:#0b1020; --fg:#e8eaf2; --muted:#a6adcd; --primary:#6c7bff; --accent:#4f46e5; --card:rgba(255,255,255,.06); --border:rgba(255,255,255,.12); --shadow:0 10px 30px rgba(0,0,0,.25), inset 0 1px 0 rgba(255,255,255,.06); --header-h:56px; }
:root[data-theme='light'] { --bg:#f7f8fc; --fg:#0e1020; --muted:#5b617a; --primary:#3b5bff; --accent:#4f46e5; --card:#ffffff; --border:rgba(0,0,0,.08); --shadow:0 8px 24px rgba(0,0,0,.08), inset 0 1px 0 rgba(255,255,255,.9); }
* { box-sizing: border-box; }
body { font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial; margin: 0; color: var(--fg); background: var(--bg); transition: background .25s ease, color .25s ease; }
html { scroll-behavior: smooth; }
.background { position: fixed; inset: 0; background: radial-gradient(1200px 600px at 10% 0%, rgba(108,123,255,.25), transparent), radial-gradient(1000px 600px at 90% 10%, rgba(79,70,229,.25), transparent); pointer-events: none; }
.site-header { position: sticky; top: 0; backdrop-filter: saturate(140%) blur(8px); background: rgba(10,12,24,.6); border-bottom: 1px solid var(--border); z-index: 10; }
:root[data-theme='light'] .site-header { background: rgba(255,255,255,.7); }
.site-header .wrap { max-width: 1100px; margin: 0 auto; padding: 12px 16px; display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: .2px; }
.brand svg { color: var(--primary); }
.nav a { color: var(--fg); text-decoration: none; opacity: .85; margin-left: 16px; }
.nav a:hover { opacity: 1; color: var(--primary); }
.nav a.active { color: var(--primary); position: relative; }
.nav a.active::after { content: ""; position: absolute; left: 0; right: 0; bottom: -10px; height: 2px; background: var(--primary); border-radius: 2px; opacity: .9; }
.theme-btn { margin-left: 16px; background: transparent; border: 1px solid var(--border); color: var(--fg); padding: 6px 10px; border-radius: 10px; cursor: pointer; }
select.theme-btn { padding: 6px 10px; appearance: none; background: rgba(255,255,255,.04); }
 :root[data-theme='light'] select.theme-btn { background: #fff; }
.container { max-width: 1100px; margin: 32px auto; padding: 0 16px; }
.container section { scroll-margin-top: var(--header-h); }
.hero { text-align: center; margin: 40px 0 24px; }
.hero h1 { margin: 0 0 8px; font-size: 36px; line-height: 1.15; }
.hero p { opacity: .85; margin: 0; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 16px; padding: 24px; box-shadow: var(--shadow); }
.drop { border: 2px dashed rgba(255,255,255,.18); border-radius: 14px; padding: 28px; text-align: center; margin: 12px 0 16px; transition: .2s border, .2s background; }
.drop.rich { background: rgba(255,255,255,.02); }
.drop.dragover { border-color: var(--primary); background: rgba(108,123,255,.08); }
.drop-inner { display: grid; grid-template-columns: 72px 1fr; gap: 16px; align-items: center; justify-content: center; max-width: 720px; margin: 0 auto; }
.drop-illustration { font-size: 42px; }
.drop-text h3 { margin: 0 0 6px; }
.hint { display: block; opacity: .7; margin-top: 6px; }
.button { display: inline-block; background: linear-gradient(135deg, var(--primary), var(--accent)); color: white; padding: 10px 14px; border-radius: 10px; cursor: pointer; margin-top: 6px; box-shadow: 0 6px 18px rgba(108,123,255,.35); }
.button input { display: none; }
.actions { display: flex; align-items: center; gap: 12px; margin: 8px 0 10px; }
button#convert { background: linear-gradient(135deg, #16a34a, #22c55e); color: white; padding: 10px 16px; border: 0; border-radius: 10px; cursor: pointer; box-shadow: 0 6px 18px rgba(34,197,94,.35); font-weight: 600; }
button#convert .btn-icon { margin-right: 6px; }
button#convert[disabled] { background: #6b7280; box-shadow: none; cursor: not-allowed; }
#status { opacity: .85; }
.file-grid { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 10px; }
.file-grid li { border: 1px solid var(--border); background: rgba(255,255,255,.03); border-radius: 10px; padding: 10px 12px; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 12px; display: flex; align-items: center; justify-content: space-between; }
:root[data-theme='light'] .file-grid li { background: #fff; }
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin: 22px 0 40px; }
.feature { background: var(--card); border: 1px solid var(--border); border-radius: 14px; padding: 16px; }
.site-footer { border-top: 1px solid var(--border); padding: 16px; opacity: .85; }
.site-footer .wrap { max-width: 1100px; margin: 0 auto; display: flex; align-items: center; gap: 10px; color: var(--muted); }