* {
    box-sizing: border-box;
}

:root {
    --bg-0: #050a13;
    --bg-1: #071426;
    --glass: rgba(255, 255, 255, .08);
    --glass-strong: rgba(255, 255, 255, .11);
    --glass-line: rgba(255, 255, 255, .18);
    --glass-line-soft: rgba(255, 255, 255, .12);
    --text: #f7fbff;
    --muted: rgba(247, 251, 255, .7);
    --muted-soft: rgba(247, 251, 255, .52);
    --blue: #88aee6;
    --blue-deep: #17365f;
    --shadow: rgba(0, 0, 0, .36);
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg-1);
    color: var(--text);
    font-family: "Helvetica Neue", Arial, sans-serif;
}

html {
    background: var(--bg-0);
    min-height: 100%;
}

.page {
    margin: 0 auto;
    max-width: 1080px;
    padding: 34px 36px 44px;
    position: relative;
}

.app-header {
    align-items: center;
    display: flex;
    justify-content: space-between;
    margin: 0 0 28px;
}

.brand {
    color: var(--text);
    font-size: clamp(25px, 3vw, 34px);
    line-height: 1;
    text-decoration: none;
}

.brand span {
    color: rgba(247, 251, 255, .58);
    font-weight: 300;
}

.app-header p {
    color: var(--muted);
    font-size: 15px;
    margin: 0;
}

.app-shell {
    background: var(--glass);
    border: 1px solid var(--glass-line);
    border-radius: 14px;
    box-shadow: 0 24px 70px var(--shadow);
    min-height: 360px;
    overflow: hidden;
    position: relative;
}

@supports (backdrop-filter: blur(18px)) {
    .app-shell,
    .drop-zone,
    .result-box {
        backdrop-filter: blur(18px);
    }
}

.panel {
    padding: 42px;
}

.upload-form {
    display: grid;
    gap: 24px;
}

.form-heading,
.panel-copy {
    max-width: 850px;
}

.eyebrow {
    border: 1px solid var(--glass-line-soft);
    border-radius: 999px;
    color: var(--blue);
    display: inline-flex;
    font-size: 12px;
    font-weight: 800;
    letter-spacing: .12em;
    margin: 0 0 18px;
    padding: 8px 13px;
    text-transform: uppercase;
}

h1 {
    color: var(--text);
    font-size: clamp(38px, 5vw, 64px);
    font-weight: 800;
    line-height: 1.06;
    margin: 0 0 18px;
}

h2 {
    color: var(--text);
    font-size: 16px;
    margin: 0 0 12px;
    text-transform: uppercase;
}

.lead {
    color: var(--muted);
    font-size: 20px;
    line-height: 1.5;
    margin: 0;
}

.form-lead {
    max-width: 720px;
}

.drop-grid {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.drop-zone {
    background: var(--glass-strong);
    border: 1px solid var(--glass-line-soft);
    border-radius: 12px;
    cursor: pointer;
    display: grid;
    gap: 16px;
    min-height: 190px;
    padding: 24px;
    position: relative;
    transition: border-color .18s ease, background .18s ease, transform .18s ease;
}

.drop-zone::after {
    border: 1px dashed rgba(247, 251, 255, .28);
    border-radius: 9px;
    content: "";
    inset: 12px;
    pointer-events: none;
    position: absolute;
}

.drop-zone:hover,
.drop-zone.is-dragging {
    background: rgba(255, 255, 255, .14);
    border-color: rgba(247, 251, 255, .42);
}

.drop-zone input {
    height: 1px;
    opacity: 0;
    pointer-events: none;
    position: absolute;
    width: 1px;
}

.drop-zone-label {
    color: var(--text);
    font-size: 14px;
    font-weight: 800;
    letter-spacing: .04em;
    text-transform: uppercase;
}

.drop-zone-label strong {
    color: var(--blue);
}

.drop-zone-action {
    align-self: end;
    color: var(--text);
    font-size: clamp(22px, 2.3vw, 30px);
    font-weight: 750;
    line-height: 1.12;
    max-width: 320px;
}

.drop-zone-note {
    color: var(--muted);
    font-size: 14px;
    line-height: 1.35;
}

.selected-files {
    background: rgba(0, 0, 0, .2);
    border: 1px solid rgba(255, 255, 255, .1);
    border-radius: 8px;
    color: var(--muted);
    display: block;
    font-size: 13px;
    line-height: 1.35;
    min-height: 42px;
    overflow-wrap: anywhere;
    padding: 11px 12px;
}

button,
.back-link,
.download-link {
    background: var(--blue-deep);
    border: 1px solid rgba(247, 251, 255, .24);
    border-radius: 8px;
    box-shadow: none;
    color: var(--text);
    cursor: pointer;
    display: inline-block;
    font: inherit;
    font-size: 18px;
    font-weight: 760;
    justify-self: start;
    padding: 14px 20px;
    text-decoration: none;
}

button:hover,
.back-link:hover,
.download-link:hover {
    background: #21466f;
}

.result-grid {
    display: grid;
    gap: 18px;
    margin-top: 4px;
    max-width: 900px;
}

.result-box {
    background: var(--glass);
    border: 1px solid var(--glass-line-soft);
    border-radius: 16px;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, .12);
    padding: 22px;
}

.result-box p {
    color: var(--muted);
    line-height: 1.45;
    margin: 0 0 12px;
}

.result-box-error,
.result-box-warning {
    background: rgba(255, 255, 255, .08);
    border-color: rgba(136, 174, 230, .32);
}

.source-label {
    color: var(--text) !important;
    font-size: 14px;
    font-weight: 800;
    margin-top: 14px !important;
    text-transform: uppercase;
}

.file-list {
    color: var(--muted);
    margin: 0;
    padding-left: 20px;
}

.file-list li {
    margin-bottom: 6px;
}

.back-link {
    margin-top: 22px;
}

.download-link {
    font-size: 16px;
    margin-top: 16px;
    padding: 10px 14px;
}

.hint {
    color: var(--muted-soft);
    font-size: 14px;
    margin: 18px 0 0;
}

@media (max-width: 900px) {
    .page {
        padding: 22px 12px 32px;
    }

    .app-header {
        align-items: flex-start;
        gap: 12px;
        flex-direction: column;
    }

    .panel {
        padding: 38px 18px 28px;
    }

    .drop-grid {
        grid-template-columns: 1fr;
    }

    h1 {
        font-size: 36px;
    }
}