* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: linear-gradient(180deg, #f6f8fb 0%, #eef2f7 100%);
    color: #1f2937;
}

.page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 40px 16px;
}

.hero {
    text-align: center;
    margin-bottom: 24px;
    max-width: 760px;
}

.hero h1 {
    margin: 0 0 12px;
    font-size: 2.3rem;
}

.hero p {
    margin: 0;
    font-size: 1.05rem;
    color: #4b5563;
}

.card {
    width: 100%;
    max-width: 760px;
    background: #ffffff;
    border-radius: 18px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    padding: 28px;
}

.upload-form {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.dropzone {
    display: block;
    border: 2px dashed #cbd5e1;
    border-radius: 16px;
    padding: 28px;
    text-align: center;
    background: #f8fafc;
    cursor: pointer;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.dropzone:hover {
    border-color: #2563eb;
    transform: translateY(-1px);
}

.drop-title {
    display: block;
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.drop-subtitle {
    display: block;
    color: #6b7280;
    margin-bottom: 12px;
}

input[type="file"] {
    width: 100%;
}

.options {
    display: grid;
    gap: 10px;
}

.quality-readout {
    font-weight: 700;
    color: #111827;
}

button,
.back-link {
    display: inline-block;
    background: #2563eb;
    color: #ffffff;
    border: none;
    border-radius: 12px;
    padding: 14px 18px;
    font-size: 1rem;
    font-weight: 700;
    text-decoration: none;
    cursor: pointer;
    transition: background 0.2s ease;
}

button:hover,
.back-link:hover {
    background: #1d4ed8;
}

.info {
    margin-top: 28px;
    border-top: 1px solid #e5e7eb;
    padding-top: 20px;
}

.info h2 {
    margin-top: 0;
}

.info ol {
    margin: 0;
    padding-left: 20px;
    color: #4b5563;
}

.footer {
    text-align: center;
    color: #6b7280;
    margin-top: 20px;
    font-size: 0.95rem;
}

.error-card {
    text-align: center;
    margin-top: 60px;
}

@media (max-width: 640px) {
    .hero h1 {
        font-size: 1.8rem;
    }

    .card {
        padding: 20px;
    }
}