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

:root {
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --bg: #F9FAFB;
    --surface: #FFFFFF;
    --text: #111827;
    --text-muted: #6B7280;
    --border: #E5E7EB;
    --radius: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
}

nav {
    display: flex;
    gap: 28px;
}

nav a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover { color: var(--primary); }

/* Hero */
.hero {
    padding: 64px 0 48px;
    text-align: center;
}

.hero h1 {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.hero > .container > p {
    color: var(--text-muted);
    font-size: 18px;
    margin-bottom: 40px;
}

/* Upload area */
.upload-area {
    max-width: 600px;
    margin: 0 auto;
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 48px 32px;
    background: var(--surface);
    cursor: pointer;
    transition: border-color 0.2s, background 0.2s;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary);
    background: #EEF2FF;
}

.upload-icon { margin-bottom: 16px; }

.upload-text {
    font-size: 16px;
    color: var(--text);
    margin-bottom: 8px;
}

.browse-link {
    color: var(--primary);
    cursor: pointer;
    font-weight: 600;
    text-decoration: underline;
}

.upload-hint {
    font-size: 13px;
    color: var(--text-muted);
}

/* Progress */
.progress-area {
    max-width: 600px;
    margin: 24px auto 0;
    background: var(--surface);
    border-radius: var(--radius);
    padding: 20px 24px;
    border: 1px solid var(--border);
}

.file-item {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
}

.file-info {
    flex: 1;
    min-width: 0;
    display: flex;
    justify-content: space-between;
}

.file-name {
    font-weight: 600;
    font-size: 14px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-size {
    font-size: 13px;
    color: var(--text-muted);
    flex-shrink: 0;
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 3px;
    width: 0%;
    transition: width 0.3s ease;
}

.progress-pct {
    font-size: 13px;
    font-weight: 600;
    color: var(--primary);
    min-width: 40px;
    text-align: right;
}

/* Features */
.features {
    padding: 48px 0;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    text-align: center;
}

.feature-icon {
    font-size: 32px;
    margin-bottom: 12px;
}

.feature-card h3 {
    font-size: 16px;
    margin-bottom: 8px;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-muted);
}

/* Stats */
.stats {
    padding: 32px 0 64px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
}

.stat-label {
    font-size: 14px;
    color: var(--text-muted);
}

/* Footer */
footer {
    margin-top: auto;
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 40px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 32px;
}

footer h4 {
    margin-bottom: 12px;
    font-size: 15px;
}

footer p, footer li {
    font-size: 14px;
    color: var(--text-muted);
}

footer ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

footer a {
    color: var(--text-muted);
    text-decoration: none;
}

footer a:hover { color: var(--primary); }

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 20px;
    text-align: center;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 { font-size: 28px; }
    .feature-grid, .stats-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 24px; }
    nav { gap: 16px; }
}