:root {
    --bg-color: #0d1117;
    --card-bg: rgba(22, 27, 34, 0.6);
    --card-border: rgba(255, 255, 255, 0.1);
    --text-primary: #c9d1d9;
    --text-secondary: #8b949e;
    --accent: #58a6ff;
    --accent-hover: #3182ce;
    --error-bg: rgba(248, 81, 73, 0.1);
    --error-border: rgba(248, 81, 73, 0.4);
    --error-text: #ff7b72;
    --success: #3fb950;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-family);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    line-height: 1.5;
    background-image: radial-gradient(circle at top, rgba(88, 166, 255, 0.05) 0%, transparent 40%);
}

.app-container {
    width: 100%;
    max-width: 800px;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

header {
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 600;
    letter-spacing: -0.5px;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #ffffff, #8b949e);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header h1 span {
    font-size: 1.25rem;
    font-weight: 400;
    color: var(--accent);
    -webkit-text-fill-color: var(--accent);
    vertical-align: middle;
}

header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2rem;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

textarea {
    width: 100%;
    background: rgba(13, 17, 23, 0.8);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 1rem;
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 1rem;
    resize: vertical;
    transition: border-color 0.2s, box-shadow 0.2s;
}

textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}

textarea:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn {
    background: var(--accent);
    color: #ffffff;
    border: none;
    border-radius: 8px;
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font-family);
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    width: 100%;
}

.btn:hover:not(:disabled) {
    background: var(--accent-hover);
}

.btn:active:not(:disabled) {
    transform: translateY(1px);
}

.btn:disabled {
    background: var(--card-border);
    color: var(--text-secondary);
    cursor: not-allowed;
}

.settings-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

select {
    width: 100%;
    background: rgba(13, 17, 23, 0.8);
    border: 1px solid var(--card-border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 0.95rem;
    cursor: pointer;
    appearance: none;
}

select:focus {
    outline: none;
    border-color: var(--accent);
}

select:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

input[type="range"] {
    width: 100%;
    margin-top: 0.5rem;
    accent-color: var(--accent);
    cursor: pointer;
}

input[type="range"]:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.checkbox-group {
    display: flex;
    align-items: center;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
    color: var(--text-primary);
    cursor: pointer;
}

input[type="checkbox"] {
    width: 1.125rem;
    height: 1.125rem;
    accent-color: var(--accent);
    cursor: pointer;
}

input[type="checkbox"]:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.status-container {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
    padding: 0.5rem;
    border-radius: 6px;
    background: rgba(0, 0, 0, 0.2);
}

.status-indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--accent);
    position: relative;
    box-shadow: 0 0 8px var(--accent);
}

.status-indicator.success {
    background-color: var(--success);
    box-shadow: 0 0 8px var(--success);
}

.status-indicator.error {
    background-color: var(--error-text);
    box-shadow: 0 0 8px var(--error-text);
}

.status-indicator.processing {
    animation: pulse 1s infinite alternate;
}

@keyframes pulse {
    0% { transform: scale(0.95); opacity: 0.7; }
    100% { transform: scale(1.1); opacity: 1; }
}

.audio-output {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    padding-top: 1rem;
    border-top: 1px solid var(--card-border);
}

audio {
    width: 100%;
    height: 48px;
    border-radius: 8px;
    outline: none;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.6rem 1.25rem;
    border: 1px solid var(--accent);
    border-radius: 8px;
    color: var(--accent);
    font-family: var(--font-family);
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: background-color 0.2s, color 0.2s, transform 0.1s;
}

.download-btn:hover {
    background: var(--accent);
    color: #ffffff;
}

.download-btn:active {
    transform: translateY(1px);
}

/* Customizing audio player for webkit */
audio::-webkit-media-controls-panel {
    background-color: rgba(22, 27, 34, 1);
}
audio::-webkit-media-controls-current-time-display,
audio::-webkit-media-controls-time-remaining-display {
    color: var(--text-primary);
}

.error-banner {
    background: var(--error-bg);
    border: 1px solid var(--error-border);
    color: var(--error-text);
    padding: 1rem;
    border-radius: 8px;
    font-size: 0.875rem;
}

.hidden {
    display: none !important;
}

.loader {
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #ffffff;
    animation: spin 1s ease-in-out infinite;
}

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