body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #1e1e1e;
    color: #ffffff;
}

.container {
    text-align: center;
    background-color: #2d2d2d;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    max-width: 400px;
    width: 100%;
}

h1 {
    margin-bottom: 2rem;
    font-weight: 300;
    color: #61dafb;
}

.file-input-container {
    margin-bottom: 1rem;
}

.file-input {
    display: none;
}

.file-label {
    display: inline-block;
    padding: 12px 24px;
    background-color: #61dafb;
    color: #1e1e1e;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.3s ease;
    font-weight: 600;
}

.file-label:hover {
    background-color: #4fa8c7;
    transform: translateY(-2px);
}

.big-number {
    font-size: 3rem;
    font-weight: bold;
    margin: 2rem 0;
    color: #61dafb;
    transition: all 0.5s ease;
}

.loading-bar {
    width: 100%;
    height: 6px;
    background-color: #444444;
    border-radius: 3px;
    overflow: hidden;
    margin-top: 1rem;
}

.loading-progress {
    width: 0;
    height: 100%;
    background-color: #61dafb;
    transition: width 0.5s ease-in-out;
}

.hidden {
    display: none;
}

.error-message {
    color: #ff6b6b;
    margin-top: 1rem;
    font-weight: 500;
}