:root {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #38bdf8;
    --accent-hover: #0ea5e9;
    --border-color: #334155;
    --success-color: #4ade80;
    --error-color: #f87171;
    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem;
}

.app-container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
}

.app-header {
    text-align: center;
    margin-bottom: 3rem;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--accent-color), #818cf8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Upload Section */
.upload-section {
    animation: fadeIn 0.5s ease-out;
}

.drop-zone {
    background-color: var(--card-bg);
    border: 2px dashed var(--border-color);
    border-radius: 1rem;
    padding: 4rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--accent-color);
    background-color: rgba(56, 189, 248, 0.05);
    transform: translateY(-2px);
}

.icon-container {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.drop-zone h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.drop-zone p {
    color: var(--text-secondary);
}

.privacy-note {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
    opacity: 0.8;
}

/* Processing Section */
.processing-section {
    text-align: center;
    padding: 3rem 0;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--accent-color);
    border-radius: 50%;
    margin: 0 auto 1.5rem;
    animation: spin 1s linear infinite;
}

.progress-bar-container {
    width: 100%;
    height: 6px;
    background-color: var(--card-bg);
    border-radius: 3px;
    margin-top: 1.5rem;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-color), #818cf8);
    width: 0%;
    transition: width 0.3s ease;
}

/* Results Section */
.results-section {
    animation: slideUp 0.5s ease-out;
}

.summary-card {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 1rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.summary-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.summary-item .label {
    color: var(--text-secondary);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}

.summary-item .value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.value-button {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    line-height: 1.1;
}

.value-button:hover {
    color: var(--accent-color);
}

.wpm-control {
    margin-top: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.wpm-control input {
    width: 90px;
    padding: 0.35rem 0.5rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    background: rgba(15, 23, 42, 0.6);
    color: var(--text-primary);
}

.btn-link {
    background: transparent;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    font-weight: 600;
}

.btn-link:hover {
    color: var(--accent-hover);
}

.details-container h3 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

.details-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1rem;
}

.toggle-group {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.toggle-label {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
}

.toggle-label input {
    accent-color: var(--accent-color);
}

.table-wrapper {
    background-color: var(--card-bg);
    border-radius: 1rem;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.results-table {
    width: 100%;
    border-collapse: collapse;
}

.results-table th, .results-table td {
    padding: 1rem 1.5rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.results-table th {
    background-color: rgba(15, 23, 42, 0.5);
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.results-table tr:last-child td {
    border-bottom: none;
}

.results-table .text-right {
    text-align: right;
}

.btn-secondary {
    display: block;
    margin: 2rem auto 0;
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.2s;
}

.btn-secondary:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

footer {
    margin-top: 4rem;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

footer a {
    color: var(--text-secondary);
    text-decoration: underline;
}

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

.hidden {
    display: none !important;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 600px) {
    .summary-card {
        grid-template-columns: 1fr;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .app-container {
        padding: 0;
    }
}