.hero {
  text-align: center;
  padding: 6rem 0 4rem;
}

.hero h1 {
  margin-bottom: 1rem;
  font-size: 3rem;
  line-height: 1.2;
  font-family: 'Roboto', sans-serif;
}

.hero h1 span {
  color: var(--primary);
}

.hero p {
  max-width: 600px;
  margin: 0 auto 1rem;
  color: var(--secondary);
}

.card {
    background-color: var(--card-bg, var(--surface-color));
    border-radius: 8px;
    box-shadow: var(--shadow);
    padding: 2.5rem;
    margin: 0 auto;
    transition: all 0.3s ease;
    text-align: center;
    max-width: 900px;
}

header .header-content {
    align-items: center; /* Ensure vertical alignment of header items */
}

.tabs {
    display: flex;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 2rem;
    justify-content: center;
}

.tab {
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--muted-text);
    background-color: transparent;
    border: none;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tab:hover {
    background-color: var(--surface-subtle);
    color: var(--text-color);
}

.tab.active {
    color: var(--primary);
    border-bottom: 3px solid var(--primary);
}

.tab-content {
    display: none;
    animation: fadeIn 0.5s;
    text-align: center;
}

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

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

.form-group {
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-secondary {
    background-color: #475569;
    color: #fff;
}

.btn-secondary:hover {
    background-color: #334155;
}

.button-group {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

.error {
    color: #d9534f;
    background-color: #f2dede;
    border: 1px solid #ebccd1;
    border-radius: 4px;
    padding: 1rem;
    margin-top: 1.5rem;
}

.success {
    display: none;
}

.loading {
    display: none;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    font-size: 1.1rem;
    color: var(--muted-text);
    margin-top: 2rem;
}

.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--surface-strong);
    border-top: 3px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

.file-upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.file-upload-area:hover {
    background-color: var(--surface-subtle);
    border-color: var(--primary);
}

.file-upload-area i {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

.file-upload-area h3 {
    margin-bottom: 0.5rem;
}

.file-upload-hint {
    color: var(--muted-text);
    font-size: 0.9rem;
}

.file-upload-area input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    opacity: 0;
    width: 100%;
    height: 100%;
    cursor: pointer;
}

.supported-formats {
    margin-top: 1rem;
}

.format-tag {
    display: inline-block;
    background-color: var(--surface-strong);
    color: var(--text-color);
    padding: 0.3rem 0.6rem;
    border-radius: 4px;
    font-size: 0.8rem;
    margin: 0.2rem;
}

.batch-thumbnails, .file-list {
    margin-top: 2rem;
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
}

.tool-row {
    margin-top: 2rem;
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}


.spaced-tool-row {
    margin-top: 1.5rem;
}

.tool-col {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    width: 100%;
    max-width: 300px;
}

.tool-col label {
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.tool-col select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ccc;
    border-radius: 4px;
    box-sizing: border-box;
    transition: border-color 0.3s;
    font-size: 1rem;
}

.tool-col select:focus {
    border-color: #0056b3;
    outline: none;
}

.card button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    background-color: #0056b3;
    color: #fff;
    margin-top: 2rem;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    background-color: #004494;
}

.status-message {
    margin-top: 2rem;
    padding: 1rem;
    border-radius: 4px;
    display: flex;
    align-items: center;
    gap: 1rem;
    justify-content: center;
    font-weight: 500;
}

.status-processing {
    background-color: #e0f2f7;
    color: #0056b3;
    border: 1px solid #b3e0f2;
}

.status-completed {
    background-color: #e6faed;
    color: #28a745;
    border: 1px solid #a6e0b9;
}

.status-error {
    background-color: #fcebeb;
    color: #dc3545;
    border: 1px solid #f2b3b3;
}

.preview-container {
    margin-top: 2rem;
    padding: 1.5rem;
    background-color: #f9f9f9;
    border-radius: 8px;
    border: 1px solid #e9ecef;
    text-align: center;
}

.preview-container audio,
.preview-container video {
    max-width: 100%;
    margin-top: 1rem;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    background-color: #28a745;
    color: #fff;
    text-decoration: none;
    margin-top: 1rem;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    background-color: #218838;
}

.progress-modal-message:empty {
    display: none;
}

.convert-now-btn {
    display: block;
    background-color: #dc3545;
    color: #fff;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    width: 100%;
    max-width: 400px;
    margin: 2rem auto 0;
}

.convert-now-btn:hover {
    background-color: #c82333;
}

.center-btn-container {
    display: flex;
    justify-content: center;
}