:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-color: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --tab-inactive: #334155;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container {
    width: 100%;
    max-width: 900px;
    padding: 2rem;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

.logo {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(to right, #818cf8, #c084fc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

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

/* TABS */
.tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.tab-btn {
    background-color: var(--tab-inactive);
    color: var(--text-muted);
    border: none;
    padding: 1rem 2rem;
    border-radius: 0.75rem;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.tab-btn.active {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.tab-content {
    display: none;
    animation: fadeIn 0.5s ease;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.info-box {
    background-color: rgba(99, 102, 241, 0.1);
    border: 1px solid var(--primary-color);
    border-radius: 0.75rem;
    padding: 1rem;
    margin-bottom: 2rem;
    text-align: center;
    color: var(--text-color);
}

.upload-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

@media (max-width: 600px) {
    .upload-section {
        grid-template-columns: 1fr;
    }
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    text-align: center;
}

.card h3 {
    margin-top: 0;
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.small-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.drop-zone {
    border: 2px dashed var(--border-color);
    border-radius: 0.75rem;
    padding: 2rem 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    min-height: 180px; /* Increased height for button */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 1rem;
}

.drop-zone:hover {
    border-color: var(--primary-color);
    background: rgba(99, 102, 241, 0.1);
}

.drop-text {
    margin: 0;
    font-weight: 500;
}

.upload-btn {
    background-color: var(--card-bg);
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.2s;
}

.upload-btn:hover {
    background-color: var(--primary-color);
    color: white;
}

.preview {
    margin-top: 0.5rem;
    max-width: 100%;
}

.preview img, .preview video, .preview audio {
    max-width: 100%;
    max-height: 150px;
    border-radius: 0.5rem;
}

.primary-btn {
    width: 100%;
    padding: 1rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s;
}

.primary-btn:hover {
    background-color: var(--primary-hover);
}

.primary-btn:disabled {
    background-color: var(--tab-inactive);
    cursor: not-allowed;
}

.hidden {
    display: none;
}

.status-msg {
    margin-top: 1rem;
    text-align: center;
    color: var(--text-muted);
    padding: 1rem;
    background: rgba(0,0,0,0.2);
    border-radius: 0.5rem;
}

.result-section {
    margin-top: 2rem;
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 1rem;
    text-align: center;
}

#face-result-video, #audio-result-player {
    width: 100%;
    max-width: 500px;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
}

.secondary-btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: transparent;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.secondary-btn:hover {
    background-color: var(--primary-color);
    color: white;
}