:root {
    --bg-color: #121212;
    --panel-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --accent-blue: #007acc;
    --danger-red: #d32f2f;
    --success-green: #388e3c;
    --border-color: #333;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: system-ui, -apple-system, sans-serif;
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.warning {
    background-color: #3f3500;
    color: #ffeb3b;
    padding: 12px;
    border-radius: 4px;
    font-size: 0.9em;
    border: 1px solid #756300;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--panel-bg);
    padding: 15px 20px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

h1, h2 { margin: 0; }
h2 { font-size: 1.2em; margin-bottom: 10px; }

button {
    background-color: #333;
    color: #fff;
    border: 1px solid #555;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 500;
}

button:hover:not(:disabled) { background-color: #444; }
button:disabled { opacity: 0.5; cursor: not-allowed; }

button.primary { background-color: var(--accent-blue); border-color: var(--accent-blue); }
button.primary:hover:not(:disabled) { background-color: #005f9e; }

button.danger { background-color: var(--danger-red); border-color: var(--danger-red); }
button.danger:hover:not(:disabled) { background-color: #b71c1c; }

select, input[type="text"] {
    background-color: #2d2d2d;
    color: #fff;
    border: 1px solid #555;
    padding: 8px;
    border-radius: 4px;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.monitor-section, .flash-section {
    background-color: var(--panel-bg);
    padding: 20px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

textarea#terminal {
    width: 100%;
    height: 300px;
    background-color: #000;
    color: #00ff00;
    font-family: 'Courier New', Courier, monospace;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    resize: vertical;
    box-sizing: border-box;
    margin-bottom: 10px;
}

.input-group { display: flex; gap: 10px; }
.input-group input { flex-grow: 1; }

.drop-zone {
    border: 2px dashed #555;
    border-radius: 6px;
    padding: 40px;
    text-align: center;
    color: #888;
    margin-bottom: 15px;
    position: relative;
}

.drop-zone.dragover { border-color: var(--accent-blue); background-color: #253340; color: #fff; }

.flash-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.progress-container {
    width: 100%;
    background-color: #333;
    border-radius: 4px;
    height: 20px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-bar {
    width: 0%;
    height: 100%;
    background-color: var(--accent-blue);
    transition: width 0.2s;
}

#flashStatus { margin: 0; font-size: 0.9em; color: #aaa; }

/* --- UI Polish Additions --- */

.header-titles {
    display: flex;
    flex-direction: column;
}

.tagline {
    margin: 4px 0 0 0;
    font-size: 0.85em;
    color: #888;
}

.status-banner {
    padding: 12px 16px;
    border-radius: 6px;
    font-weight: 500;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    transition: opacity 0.3s;
}

.status-banner.hidden {
    display: none;
    opacity: 0;
}

.status-banner.error {
    background-color: #3b1111;
    color: #ff5252;
    border: 1px solid #7a1f1f;
}

.status-banner.success {
    background-color: #113b1a;
    color: #4caf50;
    border: 1px solid #1f7a2d;
}

/* Ensure progress bar relies on actual esptool data, not fake animations */
.progress-bar {
    width: 0%;
    height: 100%;
    background-color: var(--accent-blue);
    /* Removed width transition so it precisely reflects raw esptool chunks */
    transition: background-color 0.3s; 
}