* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
    background: #f0f4f8;
    color: #0f172a;
    line-height: 1.6;
    min-height: 100vh;
}

a { color: #2563eb; text-decoration: none; }
a:hover { text-decoration: underline; }

.page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.hero {
    background: linear-gradient(135deg, #0f172a 0%, #1e40af 100%);
    color: #fff;
    padding: 48px 24px 56px;
}

.hero-inner {
    max-width: 640px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 24px;
}

.app-icon {
    flex-shrink: 0;
    width: 80px;
    height: 80px;
    border-radius: 18px;
    overflow: hidden;
    box-shadow: 0 8px 24px rgba(0,0,0,.3);
}

.app-icon svg { display: block; width: 100%; height: 100%; }

.hero-text h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 6px;
}

.hero-text p {
    font-size: 15px;
    color: #bfdbfe;
}

.content {
    max-width: 640px;
    margin: -32px auto 0;
    padding: 0 24px 48px;
    flex: 1;
    width: 100%;
}

.platform-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.tab {
    flex: 1;
    text-align: center;
    padding: 10px 16px;
    border-radius: 10px;
    background: #fff;
    color: #64748b;
    font-weight: 600;
    font-size: 14px;
    box-shadow: 0 1px 3px rgba(15,23,42,.08);
    text-decoration: none;
    transition: all .15s;
}

.tab:hover { color: #2563eb; text-decoration: none; }
.tab.active {
    background: #2563eb;
    color: #fff;
    box-shadow: 0 4px 12px rgba(37,99,235,.35);
}

.card {
    background: #fff;
    border-radius: 16px;
    padding: 28px;
    box-shadow: 0 4px 16px rgba(15,23,42,.08);
    margin-bottom: 16px;
}

.download-card { position: relative; }

.version-badge {
    display: inline-block;
    background: #dbeafe;
    color: #1d4ed8;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 999px;
    margin-bottom: 16px;
}

.version-number {
    font-size: 32px;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 8px;
}

.version-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 13px;
    color: #64748b;
    margin-bottom: 24px;
}

.download-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
    padding: 16px 24px;
    background: #2563eb;
    color: #fff;
    font-size: 16px;
    font-weight: 600;
    border-radius: 12px;
    text-decoration: none;
    transition: background .15s;
    box-shadow: 0 4px 14px rgba(37,99,235,.4);
}

.download-btn:hover {
    background: #1d4ed8;
    color: #fff;
    text-decoration: none;
}

.install-tip {
    margin-top: 14px;
    font-size: 13px;
    color: #94a3b8;
    text-align: center;
}

.release-notes {
    margin-top: 24px;
    padding-top: 20px;
    border-top: 1px solid #e2e8f0;
}

.release-notes h3 {
    font-size: 14px;
    color: #64748b;
    margin-bottom: 10px;
    font-weight: 600;
}

.notes-body {
    font-size: 14px;
    color: #334155;
    white-space: pre-wrap;
}

.checksum {
    margin-top: 16px;
    font-size: 13px;
    color: #64748b;
}

.checksum summary {
    cursor: pointer;
    user-select: none;
}

.checksum code {
    display: block;
    margin-top: 8px;
    padding: 10px 12px;
    background: #f8fafc;
    border-radius: 8px;
    font-size: 11px;
    word-break: break-all;
    color: #475569;
}

.empty-card {
    text-align: center;
    padding: 48px 28px;
}

.empty-icon { font-size: 48px; margin-bottom: 16px; }
.empty-card h2 { font-size: 18px; margin-bottom: 8px; }
.empty-card p { color: #64748b; font-size: 14px; }

.history-card h2 {
    font-size: 16px;
    margin-bottom: 16px;
    color: #334155;
}

.history-list { list-style: none; }

.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid #f1f5f9;
}

.history-item:last-child { border-bottom: none; }

.history-version {
    font-weight: 600;
    font-size: 15px;
}

.history-meta {
    display: block;
    font-size: 12px;
    color: #94a3b8;
    margin-top: 2px;
}

.history-link {
    font-size: 13px;
    font-weight: 600;
    padding: 6px 14px;
    border-radius: 8px;
    background: #f1f5f9;
    color: #2563eb;
    text-decoration: none;
    flex-shrink: 0;
}

.history-link:hover {
    background: #e2e8f0;
    text-decoration: none;
}

.footer {
    max-width: 640px;
    margin: 0 auto;
    padding: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: #94a3b8;
    width: 100%;
}

@media (max-width: 480px) {
    .hero-inner { flex-direction: column; text-align: center; }
    .hero-text h1 { font-size: 24px; }
    .version-number { font-size: 26px; }
    .card { padding: 20px; }
}