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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --error-color: #ef4444;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 900px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
    animation: fadeInDown 0.6s ease-out;
}

header h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.95;
}

main {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
}

.form-container {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
    animation: fadeInUp 0.6s ease-out;
}

.qr-form {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

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

label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.label-icon {
    font-size: 1.2rem;
}

.required {
    color: var(--error-color);
}

input[type="url"],
textarea {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s ease;
    background: var(--bg-color);
}

input[type="url"]:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    background: white;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

textarea {
    resize: vertical;
    min-height: 100px;
}

.char-count {
    text-align: right;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.file-input-wrapper {
    position: relative;
}

input[type="file"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.file-label {
    display: flex;
    flex-direction: column;
    gap: 10px;
    cursor: pointer;
}

.file-button {
    padding: 14px 24px;
    background: var(--primary-color);
    color: white;
    border-radius: 12px;
    text-align: center;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.file-button:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.file-name {
    padding: 10px 16px;
    background: var(--bg-color);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    text-align: center;
}

.error-message {
    color: var(--error-color);
    font-size: 0.85rem;
    min-height: 20px;
    display: block;
}

.submit-btn {
    padding: 16px 32px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    margin-top: 10px;
}

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

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

.submit-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.btn-loader {
    display: none;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}

.submit-btn.loading .btn-text {
    opacity: 0;
}

.submit-btn.loading .btn-loader {
    display: block;
}

.result-container {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
    animation: fadeInUp 0.6s ease-out;
}

.qr-preview {
    text-align: center;
}

.qr-preview h2 {
    margin-bottom: 30px;
    color: var(--text-primary);
    font-size: 1.8rem;
}

.qr-wrapper {
    display: inline-block;
    padding: 20px;
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

#qrCanvas {
    max-width: 100%;
    height: auto;
    display: block;
}

.qr-info {
    margin: 20px 0;
    padding: 15px;
    background: var(--bg-color);
    border-radius: 12px;
    text-align: left;
}

.qr-info p {
    margin: 8px 0;
    color: var(--text-secondary);
}

.qr-info strong {
    color: var(--text-primary);
}

.action-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 30px;
}

.action-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    color: white;
}

.download-btn {
    background: var(--success-color);
}

.download-btn:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

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

.share-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.reset-btn {
    background: var(--text-secondary);
}

.reset-btn:hover {
    background: #475569;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

footer {
    text-align: center;
    color: white;
    margin-top: 40px;
    opacity: 0.9;
    font-size: 0.9rem;
}

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

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

@keyframes spin {
    to {
        transform: translate(-50%, -50%) rotate(360deg);
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .form-container,
    .result-container {
        padding: 25px;
    }

    .action-buttons {
        flex-direction: column;
    }

    .action-btn {
        width: 100%;
        justify-content: center;
    }
}