:root {
    --bg-color: #050b14;
    --container-bg: #0a1420;
    --card-bg: #101d2e;
    --border-color: #1c3350;
    --text-primary: #e4edf7;
    --text-secondary: #7d93ad;
    --accent-sky: #38bdf8;
    --accent-amber: #fbbf24;
    --accent-green: #4ade80;
    --accent-red: #f87171;
    --panel-sunken: rgba(0, 0, 0, 0.35);
    --font-header: 'Chakra Petch', sans-serif;
    --font-body: 'Titillium Web', sans-serif;
    --font-mono: 'Space Mono', monospace;
    --shadow-color: rgba(0, 0, 0, 0.6);

    /* Shared kit mapping */
    --kit-accent: var(--accent-sky);
    --kit-accent-ink: #001824;
    --kit-accent-glow: rgba(56, 189, 248, 0.25);
    --kit-surface: var(--card-bg);
    --kit-border: var(--border-color);
    --kit-input-bg: var(--container-bg);
    --kit-error: var(--accent-red);
}

body.light-mode {
    --bg-color: #f4f8fc;
    --container-bg: #ffffff;
    --card-bg: #eaf1f8;
    --border-color: #c7d8e8;
    --text-primary: #0d1b2a;
    --text-secondary: #48607a;
    --accent-sky: #0369a1;
    --accent-amber: #b45309;
    --accent-green: #15803d;
    --accent-red: #b91c1c;
    --panel-sunken: rgba(0, 0, 0, 0.05);
    --shadow-color: rgba(0, 0, 0, 0.1);

    /* Shared kit mapping (light theme) */
    --kit-accent: var(--accent-sky);
    --kit-accent-ink: #ffffff;
    --kit-accent-glow: rgba(3, 105, 161, 0.18);
    --kit-surface: var(--card-bg);
    --kit-border: var(--border-color);
    --kit-input-bg: var(--container-bg);
    --kit-error: var(--accent-red);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    transition: background-color 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-body);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 16px;
}

.top-controls {
    position: fixed;
    top: 18px;
    right: 22px;
    z-index: 1000;
}

.theme-toggle-btn {
    background: var(--container-bg);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    padding: 9px 16px;
    border-radius: 6px;
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 0.85rem;
    cursor: pointer;
    box-shadow: 0 4px 12px var(--shadow-color);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.theme-toggle-btn:hover {
    border-color: var(--accent-sky);
}

.deck-container {
    width: 100%;
    max-width: 1000px;
    background: var(--container-bg);
    border: 2px solid var(--border-color);
    border-top: 5px solid var(--accent-sky);
    border-radius: 8px;
    padding: 28px;
    box-shadow: 0 16px 40px var(--shadow-color);
    min-height: 620px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.deck-icon {
    font-size: 2.6rem;
    text-align: center;
    margin-bottom: 8px;
}

.deck-title {
    font-family: var(--font-header);
    font-size: 1.8rem;
    color: var(--accent-sky);
    text-align: center;
    letter-spacing: 1px;
    margin-bottom: 4px;
}

.deck-subtitle {
    font-family: var(--font-mono);
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.88rem;
    margin-bottom: 20px;
    letter-spacing: 0.5px;
}

/* HUD Bar */
.hud-status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 12px 18px;
    margin-bottom: 18px;
    font-family: var(--font-mono);
    border-radius: 6px;
}

.hud-item {
    display: flex;
    flex-direction: column;
}

.hud-label {
    font-size: 0.72rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

.hud-value {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--accent-sky);
}

/* Battery Gauge */
.battery-container {
    width: 150px;
    height: 12px;
    background: var(--border-color);
    border-radius: 6px;
    overflow: hidden;
    margin-top: 4px;
}

.battery-fill {
    height: 100%;
    width: 100%;
    background: var(--accent-green);
    transition: width 0.3s ease, background-color 0.3s ease;
}

/* Flight Arena Layout */
.arena-grid {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 22px;
    align-items: start;
}

@media (max-width: 820px) {
    .arena-grid { grid-template-columns: 1fr; }
}

.canvas-wrapper {
    position: relative;
    width: 400px;
    height: 400px;
    margin: 0 auto;
    background: var(--panel-sunken);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    box-shadow: inset 0 0 20px rgba(56, 189, 248, 0.06);
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
}

/* Terminal Panel */
.terminal-panel {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    min-height: 400px;
}

.mission-box {
    background: var(--panel-sunken);
    border: 1px solid var(--border-color);
    border-left: 3px solid var(--accent-sky);
    padding: 14px 18px;
    margin-bottom: 18px;
    border-radius: 6px;
}

.mission-title {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--accent-sky);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 6px;
}

.mission-prompt {
    font-size: 1.05rem;
    line-height: 1.55;
    font-weight: 600;
}

/* Drag Controls Hint */
.drag-hint-box {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 18px;
    background: var(--panel-sunken);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 14px 16px;
}

.drag-hint-title {
    font-family: var(--font-header);
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--accent-sky);
}

.drag-hint-text {
    font-size: 0.85rem;
    line-height: 1.5;
    color: var(--text-secondary);
}

.pilot-chatter {
    font-family: var(--font-mono);
    font-size: 0.82rem;
    color: var(--accent-amber);
    font-style: italic;
    min-height: 18px;
}

/* Canvas: block touch scrolling so dragging handles works on mobile */
#flightCanvas {
    touch-action: none;
    cursor: grab;
}

/* Chart Course Button */
.chart-btn {
    background: var(--accent-sky);
    color: #001824;
    border: none;
    padding: 14px;
    font-family: var(--font-header);
    font-size: 1.02rem;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    cursor: pointer;
    border-radius: 6px;
    box-shadow: 0 4px 14px rgba(56, 189, 248, 0.25);
    width: 100%;
}

.chart-btn:hover {
    opacity: 0.92;
}

.chart-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Feedback */
.feedback-line {
    font-family: var(--font-mono);
    text-align: center;
    font-size: 0.9rem;
    font-weight: 700;
    min-height: 24px;
    margin-top: 10px;
}

.text-success { color: var(--accent-green); }
.text-error { color: var(--accent-red); }

/* General Screen Centering */
.screen-center {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 10px 0;
}

.action-btn {
    background: var(--accent-sky);
    color: #001824;
    border: none;
    padding: 14px 40px;
    font-family: var(--font-header);
    font-size: 1rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    cursor: pointer;
    margin-top: 20px;
    border-radius: 6px;
    box-shadow: 0 4px 16px rgba(56, 189, 248, 0.25);
}

.action-btn:hover {
    opacity: 0.92;
}

.brief-box {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 22px 28px;
    text-align: left;
    margin: 20px 0;
    max-width: 680px;
    line-height: 1.7;
    font-size: 0.95rem;
    border-radius: 6px;
}

.brief-box code {
    font-family: var(--font-mono);
    background: var(--panel-sunken);
    padding: 1px 6px;
    border-radius: 4px;
}

.brief-box ul { padding-left: 20px; }
.brief-box li { margin-bottom: 8px; }

footer {
    margin-top: 20px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-align: center;
}