/* Main Styles */
:root {
    --primary-color: #4e73df;
    --primary-hover: #2e59d9;
    --secondary-color: #858796;
    --success-color: #1cc88a;
    --light-gray: #f8f9fc;
    --dark-gray: #5a5c69;
    --border-color: #d1d3e2;
    --shadow: 0 0.15rem 1.75rem 0 rgba(58, 59, 69, 0.15);
    --transition: all 0.3s ease-in-out;
}

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

body {
    font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--light-gray);
    color: var(--dark-gray);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: #2c3e50;
}

p {
    margin-bottom: 1rem;
}

/* Layout */
.container {
    width: 100%;
    padding: 0 15px;
    margin: 0 auto;
}

/* Card Styles */
.calculator-container {
    max-width: 900px;
    margin: 2rem auto;
    background: white;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

.calculator-header {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
    color: white;
    padding: 2rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.calculator-header::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 200%;
    background: rgba(255, 255, 255, 0.1);
    transform: rotate(30deg);
    pointer-events: none;
}

.calculator-body {
    padding: 2.5rem;
}

/* Form Elements */
.form-label {
    font-weight: 600;
    color: var(--dark-gray);
    margin-bottom: 0.5rem;
    display: block;
}

.form-control, .form-select {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    line-height: 1.5;
    color: #6e707e;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid var(--border-color);
    border-radius: 0.35rem;
    transition: var(--transition);
}

.form-control:focus, .form-select:focus {
    color: #6e707e;
    background-color: #fff;
    border-color: #bac8f3;
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(78, 115, 223, 0.25);
}

.input-group {
    position: relative;
    display: flex;
    flex-wrap: wrap;
    align-items: stretch;
    width: 100%;
}

.input-group-text {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #6e707e;
    text-align: center;
    white-space: nowrap;
    background-color: #f8f9fc;
    border: 1px solid var(--border-color);
    border-radius: 0.35rem 0 0 0.35rem;
    border-right: none;
}

.input-group > .form-control:not(:first-child) {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

/* Slider Styles */
.slider-container {
    margin-top: 1rem;
    padding: 0 0.25rem;
}

.form-range {
    width: 100%;
    height: 1.5rem;
    padding: 0;
    background-color: transparent;
    -webkit-appearance: none;
    appearance: none;
}

.form-range:focus {
    outline: 0;
}

.form-range::-webkit-slider-thumb {
    width: 1.2rem;
    height: 1.2rem;
    margin-top: -0.5rem;
    background-color: var(--primary-color);
    border: 0;
    border-radius: 50%;
    -webkit-appearance: none;
    appearance: none;
    cursor: pointer;
    transition: var(--transition);
}

.form-range::-webkit-slider-thumb:hover {
    background-color: var(--primary-hover);
    transform: scale(1.1);
}

.form-range::-webkit-slider-runnable-track {
    width: 100%;
    height: 0.4rem;
    color: transparent;
    cursor: pointer;
    background-color: #e3e6f0;
    border-radius: 0.5rem;
}

.slider-value {
    font-weight: 700;
    color: var(--primary-color);
    text-align: center;
    display: block;
    margin-top: 0.25rem;
}

/* Button Styles */
.btn {
    display: inline-block;
    font-weight: 600;
    text-align: center;
    white-space: nowrap;
    vertical-align: middle;
    user-select: none;
    border: 1px solid transparent;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    line-height: 1.5;
    border-radius: 0.35rem;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    color: #fff;
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-primary:hover {
    color: #fff;
    background-color: var(--primary-hover);
    border-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

.btn-block {
    display: block;
    width: 100%;
}

/* Result Card */
.result-card {
    background: #f8f9fc;
    border-radius: 0.5rem;
    padding: 2rem;
    margin-top: 2rem;
    box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    border-left: 4px solid var(--primary-color);
    display: none;
    animation: fadeIn 0.5s ease-in-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    border-bottom: 1px solid #e3e6f0;
    transition: var(--transition);
}

.result-item:last-child {
    border-bottom: none;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 2px solid #e3e6f0;
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--primary-color);
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    .calculator-body {
        padding: 1.5rem;
    }
    
    .calculator-header {
        padding: 1.5rem;
    }
    
    .result-card {
        padding: 1.5rem;
    }
}

/* Utility Classes */
.text-primary {
    color: var(--primary-color) !important;
}

.text-center {
    text-align: center !important;
}

.mb-0 {
    margin-bottom: 0 !important;
}

.mt-4 {
    margin-top: 1.5rem !important;
}

/* Custom Checkbox and Radio */
.form-check {
    display: block;
    min-height: 1.5rem;
    padding-left: 1.5em;
    margin-bottom: 0.125rem;
}

.form-check-input {
    float: left;
    margin-left: -1.5em;
}

/* Tooltip */
.tooltip {
    position: relative;
    display: inline-block;
    margin-left: 0.5rem;
    cursor: help;
}

.tooltip .tooltiptext {
    visibility: hidden;
    width: 200px;
    background-color: #333;
    color: #fff;
    text-align: center;
    border-radius: 4px;
    padding: 5px;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    margin-left: -100px;
    opacity: 0;
    transition: opacity 0.3s;
    font-size: 0.8rem;
    font-weight: normal;
}

.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}