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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    padding: 40px;
    max-width: 600px;
    width: 100%;
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 30px;
    font-size: 28px;
}

.auth-section,
.url-section {
    margin-bottom: 25px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 600;
    font-size: 14px;
}

input[type="text"] {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 14px;
    transition: all 0.3s ease;
    outline: none;
}

input[type="text"]:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

small {
    display: block;
    margin-top: 5px;
    color: #999;
    font-size: 12px;
}

button {
    width: 100%;
    padding: 12px 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 10px;
}

button:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

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

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

.track-info {
    margin-top: 30px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 15px;
    animation: slideIn 0.4s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.track-details {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    align-items: center;
}

#trackCover {
    width: 120px;
    height: 120px;
    border-radius: 10px;
    object-fit: cover;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.track-text {
    flex: 1;
}

#trackTitle {
    font-size: 20px;
    color: #333;
    margin-bottom: 8px;
    font-weight: 600;
}

#trackArtist {
    font-size: 16px;
    color: #666;
}

.download-btn {
    background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    font-size: 18px;
    padding: 15px;
}

.download-btn:hover:not(:disabled) {
    box-shadow: 0 5px 20px rgba(17, 153, 142, 0.4);
}

.error {
    margin-top: 20px;
    padding: 15px;
    background: #fee;
    border: 1px solid #fcc;
    border-radius: 10px;
    color: #c33;
    font-size: 14px;
    animation: shake 0.4s ease;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

.success {
    margin-top: 20px;
    padding: 15px;
    background: #efe;
    border: 1px solid #cfc;
    border-radius: 10px;
    color: #3c3;
    font-size: 14px;
    animation: fadeIn 0.4s ease;
}

.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

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

@media (max-width: 600px) {
    .container {
        padding: 25px;
    }

    h1 {
        font-size: 24px;
    }

    .track-details {
        flex-direction: column;
        text-align: center;
    }

    #trackCover {
        width: 150px;
        height: 150px;
    }
}