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

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: #000000;
    color: #ffffff;
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding: 30px 0;
}

header h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 10px;
    color: #ffffff;
}

.subtitle {
    font-size: 16px;
    color: #cccccc;
    font-weight: 400;
}

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

.form-section {
    background-color: #111111;
    padding: 30px;
    border-radius: 8px;
    border: 1px solid #333333;
}

.variables-section h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 20px;
    color: #ffffff;
    border-bottom: 2px solid #333333;
    padding-bottom: 10px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    color: #ffffff;
}

.form-control {
    width: 100%;
    padding: 12px 15px;
    font-size: 15px;
    font-family: 'Poppins', sans-serif;
    background-color: #1a1a1a;
    border: 1px solid #333333;
    border-radius: 6px;
    color: #ffffff;
    transition: border-color 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: #ffffff;
}

.form-control::placeholder {
    color: #666666;
}

.form-control.is-invalid {
    border-color: #ff4444;
}

.form-control.is-invalid:focus {
    border-color: #ff4444;
    box-shadow: 0 0 0 2px rgba(255, 68, 68, 0.2);
}

.input-with-icon {
    position: relative;
    display: flex;
    align-items: center;
}

.validation-icon {
    position: absolute;
    right: 12px;
    display: none;
    align-items: center;
    justify-content: center;
    pointer-events: none;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: scale(0.8); }
    to { opacity: 1; transform: scale(1); }
}

/* DateTime picker specific styles */
input[type="datetime-local"]::-webkit-calendar-picker-indicator {
    filter: invert(1);
    cursor: pointer;
}

input[type="datetime-local"] {
    color-scheme: dark;
}

.form-hint {
    display: block;
    font-size: 12px;
    color: #999999;
    margin-top: 5px;
}

.button-group {
    display: flex;
    gap: 15px;
    margin-top: 30px;
}

.btn {
    padding: 12px 24px;
    font-size: 15px;
    font-weight: 500;
    font-family: 'Poppins', sans-serif;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    flex: 1;
}

.btn-primary {
    background-color: #ffffff;
    color: #000000;
}

.btn-primary:hover {
    background-color: #e0e0e0;
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: #333333;
    color: #ffffff;
    border: 1px solid #555555;
}

.btn-secondary:hover {
    background-color: #444444;
    transform: translateY(-2px);
}

.preview-section {
    background-color: #111111;
    padding: 30px;
    border-radius: 8px;
    border: 1px solid #333333;
    position: sticky;
    top: 20px;
    max-height: calc(100vh - 40px);
    overflow-y: auto;
}

.preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    border-bottom: 2px solid #333333;
    padding-bottom: 10px;
}

.preview-header h3 {
    font-size: 20px;
    font-weight: 600;
    color: #ffffff;
}

.btn-close {
    background: none;
    border: none;
    color: #ffffff;
    font-size: 28px;
    cursor: pointer;
    padding: 0;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.btn-close:hover {
    background-color: #333333;
}

.preview-content {
    background-color: #000000;
    border-radius: 6px;
    padding: 20px;
    overflow-x: auto;
}

.preview-content iframe {
    width: 100%;
    min-height: 600px;
    border: none;
    background-color: #000000;
}

@media only screen and (max-width: 968px) {
    .main-content {
        grid-template-columns: 1fr;
    }
    
    .preview-section {
        position: relative;
        top: 0;
        max-height: none;
    }
}

@media only screen and (max-width: 600px) {
    header h1 {
        font-size: 24px;
    }
    
    .form-section,
    .preview-section {
        padding: 20px;
    }
    
    .button-group {
        flex-direction: column;
    }
}