/* CSS Variables for theming */
:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --accent-color: #10b981;
    --accent-hover: #059669;
    --background: #f8fafc;
    --surface: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: 0.2s ease;
}

/* Reset and base styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* Container */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 24px 16px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 32px;
}

.logo-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 8px;
}

.logo {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
}

h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-top: 4px;
}

/* Main content */
main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Sections */
section {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

/* Text input section */
.text-input-section label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

#text-input {
    width: 100%;
    padding: 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    resize: vertical;
    transition: border-color var(--transition), box-shadow var(--transition);
    background: var(--surface);
    color: var(--text-primary);
}

#text-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

#text-input::placeholder {
    color: var(--text-secondary);
}

.char-count {
    text-align: right;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 8px;
}

/* Controls section */
.controls-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.control-group label {
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-primary);
}

/* Select styling */
select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    background: var(--surface);
    color: var(--text-primary);
    cursor: pointer;
    transition: border-color var(--transition), box-shadow var(--transition);
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 18px;
    padding-right: 44px;
}

select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

/* Range slider styling */
input[type="range"] {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--border-color);
    appearance: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition);
    box-shadow: var(--shadow-sm);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-md);
}

input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
    transition: transform var(--transition), box-shadow var(--transition);
}

input[type="range"]::-moz-range-thumb:hover {
    transform: scale(1.1);
}

/* Playback section */
.playback-section {
    text-align: center;
}

.playback-controls {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    margin-bottom: 20px;
}

/* Button styling */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition);
    box-shadow: var(--shadow-sm);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.btn:not(:disabled):hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn:not(:disabled):active {
    transform: translateY(0);
}

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

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

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

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

.btn-accent {
    background: var(--accent-color);
    color: white;
}

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

.icon {
    width: 20px;
    height: 20px;
}

/* Status and progress */
.status-container {
    margin-top: 16px;
}

.status {
    font-size: 0.875rem;
    color: var(--text-secondary);
    min-height: 24px;
    margin-bottom: 12px;
}

.status.speaking {
    color: var(--primary-color);
    font-weight: 500;
}

.status.error {
    color: #ef4444;
}

.status.success {
    color: var(--accent-color);
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
    opacity: 0;
    transition: opacity var(--transition);
}

.progress-bar.active {
    opacity: 1;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: 3px;
    width: 0%;
    transition: width 0.1s linear;
}

/* Info section */
.info-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    background: transparent;
    box-shadow: none;
    border: none;
    padding: 0;
}

.info-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.info-card h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.info-card ol,
.info-card ul {
    padding-left: 20px;
    color: var(--text-secondary);
}

.info-card li {
    margin-bottom: 8px;
    font-size: 0.9375rem;
}

.info-card li:last-child {
    margin-bottom: 0;
}

/* Footer */
footer {
    text-align: center;
    padding: 32px 16px 16px;
    margin-top: auto;
}

footer p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition);
}

footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* Mobile responsive */
@media (max-width: 640px) {
    .container {
        padding: 16px 12px;
    }

    h1 {
        font-size: 1.5rem;
    }

    .subtitle {
        font-size: 0.875rem;
    }

    section {
        padding: 16px;
    }

    .controls-section {
        grid-template-columns: 1fr;
    }

    .playback-controls {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

    .info-section {
        grid-template-columns: 1fr;
    }
}

/* Animations */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.status.speaking {
    animation: pulse 1.5s ease-in-out infinite;
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --background: #0f172a;
        --surface: #1e293b;
        --text-primary: #f1f5f9;
        --text-secondary: #94a3b8;
        --border-color: #334155;
    }

    select {
        background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    }

    input[type="range"] {
        background: var(--border-color);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus visible for keyboard navigation */
button:focus-visible,
select:focus-visible,
textarea:focus-visible,
input:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}