:root {
    --bg-darkest: #121518;
    --bg-dark: #1c2025;
    --bg-medium: #262c33;
    --bg-light: #37474f;
    --border-color: #455a64;
    --text-primary: #e0e0e0;
    --text-secondary: #90a4ae;
    --accent-blue: #4fc3f7;
    --accent-green: #2e7d32;
    --accent-red: #ef5350;
    --accent-red-dark: #c62828;
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

    --sidebar-width: 300px;
    --topbar-height: 60px;
    --border-radius: 6px;
    --transition-speed: 0.2s;
}

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

html,
body {
    height: 100%;
    font-family: var(--font-sans);
    background-color: var(--bg-darkest);
    color: var(--text-primary);
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    display: flex;
    height: calc(100vh - var(--topbar-height));
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    overflow: hidden;
}

.topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--topbar-height);
    padding: 0 16px;
    background-color: var(--bg-dark);
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
    gap: 16px;
}

.topbar .brand {
    font-weight: 600;
    font-size: 1.2rem;
    white-space: nowrap;
}

.topbar-center {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    min-width: 0;
}

#freqDial {
    display: flex;
    align-items: flex-end;
    gap: 6px;
    user-select: none;
    white-space: nowrap;
}

#freqDial .block {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

#freqDial .digits {
    display: flex;
    gap: 2px;
}

#freqDial .digit {
    position: relative;
    width: 24px;
    height: 36px;
    line-height: 36px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: var(--bg-darkest);
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.1rem;
    text-align: center;
    transition: all var(--transition-speed) ease;
}

#freqDial .digit .hit {
    position: absolute;
    left: 0;
    right: 0;
    height: 50%;
    cursor: pointer;
}

#freqDial .digit .inc {
    top: 0;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
}

#freqDial .digit .dec {
    bottom: 0;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
}

#freqDial .digit .inc:hover {
    background: rgba(79, 195, 247, 0.2);
}

#freqDial .digit .dec:hover {
    background: rgba(156, 204, 101, 0.2);
}

#freqDial .digit .inc:active {
    background: rgba(79, 195, 247, 0.4);
}

#freqDial .digit .dec:active {
    background: rgba(156, 204, 101, 0.4);
}

#freqDial .unit {
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--text-secondary);
    padding-bottom: 2px;
}

#freqDial .sep {
    align-self: center;
    padding-bottom: 10px;
    opacity: 0.6;
}

#freqDial .block.msw .digit {
    border-color: var(--accent-blue);
    box-shadow: 0 0 5px rgba(79, 195, 247, 0.5);
}

#freqDial .digit.muted {
    color: #6a7981;
    border-color: #2a343a;
    background-color: #21262b;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 28px;
    height: 28px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
}

.menu-toggle span {
    width: 100%;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
}

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-dark);
    border-right: 1px solid var(--border-color);
    padding: 1rem;
    overflow-y: auto;
    transition: transform 0.3s ease-in-out;
}

.sidebar-header {
    display: none;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-header h3 {
    margin: 0;
    font-size: 1.25rem;
}

.sidebar-close {
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-secondary);
    cursor: pointer;
    line-height: 1;
}

.spectrum-pane,
.waterfall-pane {
    flex: 1;
    display: flex;
    min-height: 0;
}

#ruler-container {
    height: 20px;
    background-color: var(--bg-darkest);
    flex-shrink: 0;
}

.waterfall-pane {
    background-color: #000;
    border-top: 1px solid var(--border-color);
}

#spectrumCanvas,
#waterfallCanvas,
#rulerCanvas {
    display: block;
    width: 100%;
    height: 100%;
}

.control-group {
    background-color: var(--bg-medium);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin-bottom: 1.5rem;
}

.group-header {
    padding: 0.75rem 1rem;
    font-weight: 600;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.9rem;
    background-color: rgba(0, 0, 0, 0.1);
}

.group-content {
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

label {
    font-size: 0.9em;
    color: var(--text-secondary);
    margin-bottom: -0.75rem;
}

.field-row>label {
    margin-bottom: 0;
}

input,
select {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 0.75rem;
    border-radius: var(--border-radius);
    font-size: 1rem;
    width: 100%;
    transition: all var(--transition-speed) ease;
}

input:focus,
select:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(79, 195, 247, 0.2);
}

.field-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.field-row input[type="number"] {
    flex: 1;
    min-width: 60px;
}

#frequencyUnitSelect {
    flex-grow: 0;
    width: auto;
    padding-right: 2.5em;
}

.field-row button {
    flex-shrink: 0;
}

.field-row>label {
    flex: 0 0 auto;
    white-space: nowrap;
    margin-right: 0.5rem;
}

.value-display {
    font-variant-numeric: tabular-nums;
    color: var(--text-secondary);
    flex-shrink: 0;
    width: 4.5ch;
    text-align: right;
}

input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    flex-grow: 1;
    min-width: 0;
    width: auto;
    height: 24px;
    background: transparent;
    outline: none;
    padding: 0;
    margin: 0 0.5rem;
    cursor: pointer;
    border: none;
}

input[type="range"]::-webkit-slider-runnable-track {
    width: 100%;
    height: 6px;
    background: var(--bg-dark);
    border-radius: 3px;
    border: 1px solid var(--border-color);
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    margin-top: -7px;
    width: 20px;
    height: 20px;
    background: var(--accent-blue);
    border-radius: 50%;
    border: 2px solid var(--bg-dark);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

input[type="range"]::-moz-range-track {
    width: 100%;
    height: 6px;
    background: var(--bg-dark);
    border-radius: 3px;
    border: 1px solid var(--border-color);
}

input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: var(--accent-blue);
    border: 2px solid var(--bg-dark);
    border-radius: 50%;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.field-row[hidden] {
    display: none;
}

#stereoEnableRow,
#stereoStatusRow {
    justify-content: space-between;
}

input[type="checkbox"] {
    -webkit-appearance: none;
    appearance: none;
    background-color: var(--bg-dark);
    margin: 0;
    padding: 0;
    color: currentColor;
    width: 22px;
    height: 22px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    display: grid;
    place-content: center;
    flex-shrink: 0;
}

input[type="checkbox"]::before {
    content: "";
    width: 12px;
    height: 12px;
    transform: scale(0);
    transition: 120ms transform ease-in-out;
    box-shadow: inset 1em 1em var(--accent-green);
    transform-origin: center;
    clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0%, 43% 62%);
}

input[type="checkbox"]:checked::before {
    transform: scale(1);
}

input[type="checkbox"]:focus {
    box-shadow: 0 0 0 3px rgba(79, 195, 247, 0.2);
}

.info-badge {
    font-weight: 600;
    color: var(--text-primary);
}

button {
    cursor: pointer;
    background-color: var(--bg-light);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    padding: 8px 16px;
    font-weight: 600;
    transition: all var(--transition-speed) ease;
    white-space: nowrap;
}

button:hover {
    background-color: #4a5c66;
}

button:active {
    background-color: #546e7a;
    transform: translateY(1px);
}

#connectButton {
    min-width: 100px;
}

#connectButton.connected {
    background-color: var(--accent-red);
    border-color: var(--accent-red-dark);
}

#connectButton.connected:hover {
    background-color: #d32f2f;
}

#connectButton.disconnected {
    background-color: var(--accent-green);
    border-color: #5a8c3c;
}

#connectButton.disconnected:hover {
    background-color: #8bc34a;
}

#frequencyOffsetReset {
    padding: 0.5rem;
    width: 44px;
    height: 44px;
    font-size: 1.2rem;
    flex-shrink: 0;
}

#spectrogramLockButton {
    width: 100%;
    padding: 0.5rem;
    font-size: 1.2rem;
}


@media (max-width: 1024px) {

    .menu-toggle {
        display: flex;
    }

    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        height: 100vh;
        width: min(85vw, 320px);
        transform: translateX(-100%);
        z-index: 1005;
        border-right: 2px solid var(--border-color);
        box-shadow: 5px 0 15px rgba(0, 0, 0, 0.3);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .sidebar-header {
        display: flex;
    }

    .sidebar-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.6);
        z-index: 999;
        opacity: 0;
        visibility: hidden;
        transition: opacity 0.3s ease, visibility 0s 0.3s;
    }

    .sidebar-overlay.visible {
        opacity: 1;
        visibility: visible;
        transition: opacity 0.3s ease;
    }

    input:not([type="checkbox"]):not([type="range"]),
    select,
    button {
        font-size: 16px;
        min-height: 48px;
    }
}

@media (max-width: 768px) {
    .topbar .brand {
        display: none;
    }

    #freqDial .digit {
        width: 20px;
        height: 30px;
        line-height: 30px;
        font-size: 1rem;
    }

    #freqDial .sep {
        padding-bottom: 8px;
    }

    #freqDial .unit {
        font-size: 0.65rem;
    }
}

@media (max-width: 480px) {
    .topbar {
        gap: 12px;
    }

    #freqDial {
        gap: 2px;
    }

    #freqDial .digits {
        gap: 1px;
    }

    #freqDial .digit {
        width: 18px;
        height: 28px;
        line-height: 28px;
        font-size: 0.9rem;
        border-radius: 4px;
    }

    #freqDial .sep {
        display: none;
    }

    #freqDial .unit {
        padding: 0;
        width: 2ch;
        text-align: left;
    }

    #connectButton {
        padding: 6px 12px;
        min-width: 80px;
        font-size: 0.85rem;
    }
}

.welcome-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    z-index: 2000;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.3s ease, visibility 0s 0s;
}

.welcome-overlay.hidden {
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0s 0.3s;
    pointer-events: none;
}

.welcome-content {
    background: var(--bg-medium);
    padding: 2rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    max-width: 500px;
    width: 90%;
    text-align: center;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
}

.welcome-content h1 {
    margin-bottom: 1rem;
    color: var(--accent-blue);
}

.welcome-content p {
    margin-bottom: 1rem;
    line-height: 1.5;
    color: var(--text-primary);
}

.welcome-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.status-indicator {
    font-size: 0.9rem;
    font-weight: 600;
    padding: 6px 12px;
    border-radius: 4px;
    background-color: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--border-color);
}

.status-indicator.supported {
    color: var(--accent-green);
    border-color: var(--accent-green);
    background-color: rgba(46, 125, 50, 0.1);
}

.status-indicator.unsupported {
    color: var(--accent-red);
    border-color: var(--accent-red);
    background-color: rgba(239, 83, 80, 0.1);
}

.welcome-content button {
    margin-top: 0;
    background-color: var(--accent-blue);
    color: var(--bg-darkest);
    border: none;
    padding: 10px 24px;
    font-size: 1rem;
}

.welcome-content button:hover {
    background-color: #81d4fa;
}