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

:root {
    --primary-color: #4A90E2;
    --secondary-color: #5A67D8;
    --text-color: #2D3748;
    --bg-color: #F7FAFC;
    --card-bg: #FFFFFF;
    --border-color: #E2E8F0;
    --success-color: #48BB78;
    --hover-color: #3182CE;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #08eba2 0%, #764ba2 100%);
    color: var(--text-color);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 30px;
}

.logo-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.header-logo {
    width: 80px;
    height: 80px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    object-fit: contain;
    background: transparent;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.95;
}

.main-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 40px;
}

.options-panel, .result-panel {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    height: fit-content;
}

.result-panel {
    position: sticky;
    top: 20px;
    text-align: center;
}

.section {
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid var(--border-color);
}

.section:last-child {
    border-bottom: none;
}

.section h2 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.input-group {
    margin-bottom: 15px;
}

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: var(--text-color);
}

.input-group input[type="text"],
.input-group input[type="url"],
.input-group input[type="email"],
.input-group input[type="tel"],
.input-group input[type="number"],
.input-group textarea,
.input-group select {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s;
}

.input-group input[type="text"]:focus,
.input-group input[type="url"]:focus,
.input-group input[type="email"]:focus,
.input-group input[type="tel"]:focus,
.input-group textarea:focus,
.input-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

.input-group textarea {
    min-height: 80px;
    resize: vertical;
}

.input-group input[type="radio"] {
    margin-right: 8px;
    margin-bottom: 8px;
}

.input-group label input[type="radio"] + span {
    display: inline-block;
    padding: 8px 15px;
    background: var(--bg-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.input-group label input[type="radio"]:checked + span {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.input-group label {
    display: inline-block;
    margin-right: 10px;
    margin-bottom: 10px;
    cursor: pointer;
}

.input-group input[type="range"] {
    width: 70%;
    margin-right: 10px;
    cursor: pointer;
}

.input-group input[type="color"] {
    width: 100px;
    height: 45px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
}

.input-group input[type="file"] {
    padding: 10px;
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
}

.input-group input[type="file"]:hover {
    border-color: var(--primary-color);
    background: rgba(74, 144, 226, 0.05);
}

#size-value,
#logo-size-value {
    display: inline-block;
    min-width: 50px;
    font-weight: 600;
    color: var(--primary-color);
}

.generate-btn,
.download-btn {
    width: 100%;
    padding: 15px 30px;
    font-size: 1.1rem;
    font-weight: 600;
    color: white;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 4px 15px rgba(74, 144, 226, 0.3);
}

.generate-btn:hover,
.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(74, 144, 226, 0.4);
}

.generate-btn:active,
.download-btn:active {
    transform: translateY(0);
}

.download-btn {
    margin-top: 10px;
    background: linear-gradient(135deg, var(--success-color) 0%, #38A169 100%);
}

#remove-logo {
    margin-top: 10px;
    padding: 8px 15px;
    background: #E53E3E;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
}

#remove-logo:hover {
    background: #C53030;
}

#qr-output {
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-color);
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
}

#qr-output canvas {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.placeholder {
    text-align: center;
    color: #A0AEC0;
    font-size: 1.2rem;
}

#download-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

footer {
    text-align: center;
    color: white;
    padding: 20px;
    opacity: 0.9;
}

/* Responsive */
@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 1fr;
    }

    .result-panel {
        position: static;
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .header-logo {
        width: 60px;
        height: 60px;
    }
    
    .logo-header {
        gap: 15px;
    }

    .options-panel, .result-panel {
        padding: 20px;
    }

    .section h2 {
        font-size: 1.1rem;
    }
}

/* Touch events support */
button {
    touch-action: manipulation;
    -ms-touch-action: manipulation;
}

/* Animación de carga */
@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading {
    animation: spin 1s linear infinite;
}