/* Buffalo Stone Theme - Dark gray background, white text */
:root {
    --bg-color: #696969;
    --text-color: #ffffff;
    --nav-bg: #333;
    --accent-blue: #83B0D6;
    --accent-blue-dark: #4A85BE;
    --accent-red: #DE3B3E;
    --accent-red-light: #EC6C5B;
    --accent-green: #00CC96;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

/* Top Navigation */
.topnav {
    overflow: hidden;
    background-color: var(--nav-bg);
    position: fixed;
    left: 0;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.topnav a {
    float: left;
    display: block;
    color: #f2f2f2;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    font-size: 14px;
}

.topnav a:hover {
    background-color: #ddd;
    color: black;
}

/* Main Content */
.main-content {
    padding: 70px 20px 20px 20px;
    max-width: 1400px;
    margin: 0 auto;
}

h1 {
    text-align: center;
    font-size: 32px;
    margin-bottom: 5px;
}

.subtitle {
    text-align: center;
    font-size: 14px;
    opacity: 0.8;
    margin-top: 0;
}

h3 {
    margin-top: 20px;
    margin-bottom: 10px;
}

/* Form Elements */
.input-row {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

select {
    padding: 8px 12px;
    font-size: 14px;
    border: none;
    border-radius: 4px;
    background: white;
    color: #111;
    min-width: 300px;
}

input[type="text"] {
    padding: 8px 12px;
    font-size: 14px;
    border: none;
    border-radius: 4px;
    background: white;
    color: #111;
    width: 100px;
    text-transform: uppercase;
}

button {
    padding: 8px 16px;
    font-size: 14px;
    border: none;
    border-radius: 4px;
    background: var(--accent-blue);
    color: white;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background: var(--accent-blue-dark);
}

button:disabled {
    background: #888;
    cursor: not-allowed;
}

/* Dual-Handle Range Slider */
.range-slider-container {
    width: 100%;
    max-width: 800px;
    padding: 20px 0 30px 0;
}

.range-slider {
    position: relative;
    height: 40px;
    display: flex;
    align-items: center;
}

.range-slider input[type="range"] {
    position: absolute;
    width: 100%;
    height: 40px;
    background: none;
    pointer-events: none;
    -webkit-appearance: none;
    appearance: none;
    margin: 0;
    padding: 0;
    top: 0;
}

/* Left slider (min) - pointer events on left half */
.range-slider input[type="range"]#range-min {
    z-index: 2;
}

/* Right slider (max) - always on top for right side */
.range-slider input[type="range"]#range-max {
    z-index: 3;
}

.range-slider input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    background: var(--accent-blue);
    border-radius: 50%;
    cursor: grab;
    pointer-events: auto;
    border: 2px solid white;
    box-shadow: 0 2px 6px rgba(0,0,0,0.4);
    margin-top: -8px;
    transition: transform 0.1s, box-shadow 0.1s;
}

.range-slider input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
    box-shadow: 0 3px 10px rgba(0,0,0,0.5);
}

.range-slider input[type="range"]::-webkit-slider-thumb:active {
    cursor: grabbing;
    transform: scale(1.2);
}

.range-slider input[type="range"]::-moz-range-thumb {
    width: 24px;
    height: 24px;
    background: var(--accent-blue);
    border-radius: 50%;
    cursor: grab;
    pointer-events: auto;
    border: 2px solid white;
    box-shadow: 0 2px 6px rgba(0,0,0,0.4);
}

.range-slider input[type="range"]::-moz-range-thumb:hover {
    transform: scale(1.15);
}

.range-slider input[type="range"]::-moz-range-thumb:active {
    cursor: grabbing;
}

.range-slider input[type="range"]::-webkit-slider-runnable-track {
    height: 8px;
    background: transparent;
    cursor: pointer;
}

.range-slider input[type="range"]::-moz-range-track {
    height: 8px;
    background: transparent;
    cursor: pointer;
}

.slider-track {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    left: 0;
    right: 0;
    height: 8px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 4px;
    pointer-events: none;
}

.slider-range {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    height: 8px;
    background: var(--accent-blue);
    border-radius: 4px;
    pointer-events: none;
}

/* Year ticks and labels */
.range-ticks {
    position: relative;
    width: 100%;
    height: 30px;
    margin-top: 8px;
}

.range-tick {
    position: absolute;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.range-tick .dot {
    width: 6px;
    height: 6px;
    background: rgba(255, 255, 255, 0.5);
    border-radius: 50%;
}

.range-tick.major .dot {
    width: 8px;
    height: 8px;
    background: white;
}

.range-tick .label {
    margin-top: 4px;
    font-size: 11px;
    color: white;
}

/* Loading & Error States */
.loading, .error {
    padding: 15px;
    margin: 15px 0;
    border-radius: 4px;
    text-align: center;
}

.loading {
    background: rgba(131, 176, 214, 0.2);
    border: 1px solid var(--accent-blue);
}

.error {
    background: rgba(222, 59, 62, 0.2);
    border: 1px solid var(--accent-red);
}

.hidden {
    display: none;
}

/* Charts */
.chart {
    margin: 20px 0;
    min-height: 400px;
}

/* Two Column Layout */
.two-column {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 20px 0;
}

@media (max-width: 900px) {
    .two-column {
        grid-template-columns: 1fr;
    }
}

/* Info Panel */
.info-panel {
    background: rgba(0, 0, 0, 0.1);
    padding: 15px;
    border-radius: 4px;
    font-size: 14px;
}

.info-panel h4 {
    margin-top: 0;
    color: var(--accent-blue);
}

.info-panel p {
    margin: 8px 0;
}

.info-panel .label {
    opacity: 0.8;
}

.info-panel .value {
    font-weight: bold;
}

.info-panel .summary {
    margin-top: 15px;
    line-height: 1.5;
    max-height: 200px;
    overflow-y: auto;
}

/* Educational Content */
hr {
    border: none;
    border-top: 1px solid rgba(255, 255, 255, 0.3);
    margin: 30px 0;
}

.education {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.education p {
    margin: 15px 0;
}

.education h3 {
    text-align: left;
}

.education p:has(strong) {
    text-align: left;
}

.source-link {
    text-align: center;
    font-style: italic;
    margin-top: 30px;
}

.source-link a {
    color: var(--accent-blue);
}