:root {
    --primary: #007bff;
    --primary-light: #4dabf7;
    --primary-dark: #0056b3;
    --secondary: #6c757d;
    --bg-color: #f1f4f9;
    --text-color: #212529;
    --text-muted: #6c757d;
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.4);
    --error: #dc3545;
    --success: #28a745;
    --shadow: 0 8px 32px 0 rgba(0, 123, 255, 0.15);
    --radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    background-image: 
        radial-gradient(at 0% 0%, hsla(210, 100%, 93%, 1) 0, transparent 50%), 
        radial-gradient(at 100% 100%, hsla(210, 100%, 90%, 1) 0, transparent 50%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.app-container {
    width: 100%;
    max-width: 1000px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* Entrance Animations */
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-40px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(40px); }
    to { opacity: 1; transform: translateX(0); }
}

.fade-in-down { animation: fadeInDown 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards; }
.slide-in-left { animation: slideInLeft 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards; }
.slide-in-right { animation: slideInRight 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards; }

/* Header */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--primary-dark);
}

.logo i {
    font-size: 32px;
}

.logo h1 {
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.5px;
}

/* Main Content Layout */
.app-main {
    display: grid;
    grid-template-columns: 1fr 340px;
    gap: 20px;
}

@media (max-width: 768px) {
    .app-main {
        grid-template-columns: 1fr;
    }
}

/* Glass Panels */
.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px;
    display: flex;
    flex-direction: column;
}

/* Input Section */
.input-section {
    min-height: 400px;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.section-header h2 {
    font-size: 14px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
}

.char-count {
    font-size: 12px;
    color: var(--text-muted);
}

/* Voice Reveal Animation */
.voice-reveal {
    max-height: 0;
    opacity: 0;
    transform: translateY(-10px);
    overflow: hidden;
    transition: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
    pointer-events: none;
}

.voice-reveal.is-visible {
    max-height: 200px;
    opacity: 1;
    transform: translateY(0);
    pointer-events: all;
    margin-top: 10px;
}

textarea {
    flex: 1;
    width: 100%;
    background: transparent;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    padding: 16px;
    font-family: inherit;
    font-size: 18px;
    line-height: 1.6;
    color: var(--text-color);
    resize: none;
    transition: var(--transition);
}

textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.1);
}

.input-footer {
    display: flex;
    justify-content: flex-end;
    margin-top: 16px;
}

/* Controls Panel */
.controls-panel {
    gap: 24px;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.control-group label {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-muted);
}

.label-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.label-row span {
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
    background: rgba(0, 123, 255, 0.1);
    padding: 2px 8px;
    border-radius: 4px;
}

/* Select Styling */
.custom-select {
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    border: 1px solid #e1e8ed;
    background-color: white;
    font-family: inherit;
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
}

.custom-select:focus {
    outline: none;
    border-color: var(--primary);
}

/* Range Input Styling */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    background: #e1e8ed;
    border-radius: 5px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    background: var(--primary);
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
    border: 3px solid white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

input[type="range"]:active::-webkit-slider-thumb {
    transform: scale(1.2);
}

/* Buttons */
.playback-controls {
    display: flex;
    gap: 12px;
    height: 48px; /* Fixed height to prevent layout shift during animation */
    overflow: hidden;
}

#btn-stop {
    opacity: 0;
    max-width: 0;
    padding: 0;
    margin: 0;
    pointer-events: none;
    transform: scale(0.95); /* Start slightly smaller */
    transition: 
        opacity 0.4s ease,
        max-width 0.6s cubic-bezier(0.34, 1.56, 0.64, 1),
        padding 0.6s cubic-bezier(0.34, 1.56, 0.64, 1),
        transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    overflow: hidden;
    white-space: nowrap;
}

.playing #btn-stop {
    opacity: 1;
    max-width: 200px;
    padding: 12px 24px;
    pointer-events: all;
    transform: scale(1); /* Return to full size */
}

.btn-primary, .btn-secondary, .btn-danger, .btn-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 8px;
    font-family: inherit;
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    box-shadow: 0 4px 12px rgba(0, 123, 255, 0.3);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 8px 24px rgba(0, 123, 255, 0.4);
}

.btn-primary:active {
    transform: translateY(0) scale(0.98);
}

.btn-secondary {
    background-color: #e9ecef;
    color: var(--text-color);
}

.btn-secondary:hover {
    background-color: #dee2e6;
}

.btn-danger {
    background-color: #fff1f2;
    color: var(--error);
    border: 1px solid #fecaca;
}

.btn-danger:hover {
    background-color: #ffe4e6;
}

.btn-toggle {
    background-color: white;
    color: var(--primary);
    border: 1px solid var(--primary);
    padding: 8px 16px;
}

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

.main-btn {
    flex: 1;
}

.full-width {
    width: 100%;
}

/* Progress Footer */
.app-footer {
    padding: 10px 20px;
}

.progress-container {
    width: 100%;
    height: 6px;
    background: #e1e8ed;
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 12px;
}

.progress-bar {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary-light), var(--primary));
    transition: width 0.1s linear;
}

.footer-status {
    font-size: 12px;
    color: var(--text-muted);
}

/* States */
.playing .progress-bar {
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.7; }
    100% { opacity: 1; }
}