:root {
    --bg: #f5f6f8;
    --surface: #ffffff;
    --text: #16181d;
    --text-muted: #6b7280;
    --border: #e3e5e9;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --accent-contrast: #ffffff;
    --chip-bg: #eef0f3;
    --chip-active-bg: #16181d;
    --chip-active-text: #ffffff;
    --danger: #dc2626;
    --radius: 12px;
    --shadow: 0 1px 2px rgba(16, 24, 40, 0.06), 0 1px 3px rgba(16, 24, 40, 0.08);
}

:root[data-theme="dark"] {
    --bg: #0f1115;
    --surface: #181b21;
    --text: #e8eaed;
    --text-muted: #9aa0ab;
    --border: #2a2e37;
    --accent: #3b82f6;
    --accent-hover: #60a5fa;
    --accent-contrast: #0f1115;
    --chip-bg: #23262e;
    --chip-active-bg: #e8eaed;
    --chip-active-text: #16181d;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 2px 6px rgba(0, 0, 0, 0.35);
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: #0f1115;
        --surface: #181b21;
        --text: #e8eaed;
        --text-muted: #9aa0ab;
        --border: #2a2e37;
        --accent: #3b82f6;
        --accent-hover: #60a5fa;
        --accent-contrast: #0f1115;
        --chip-bg: #23262e;
        --chip-active-bg: #e8eaed;
        --chip-active-text: #16181d;
        --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 2px 6px rgba(0, 0, 0, 0.35);
    }
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    transition: background 0.2s ease, color 0.2s ease;
}

.topbar {
    border-bottom: 1px solid var(--border);
    background: var(--surface);
}

.topbar-inner {
    max-width: 960px;
    margin: 0 auto;
    padding: 16px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand {
    font-size: 1.15rem;
    font-weight: 700;
    margin: 0;
}

.icon-btn {
    border: 1px solid var(--border);
    background: var(--chip-bg);
    color: var(--text);
    width: 40px;
    height: 40px;
    border-radius: 999px;
    cursor: pointer;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon-btn:hover {
    filter: brightness(1.05);
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 24px 20px 60px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}

@media (min-width: 760px) {
    .container {
        grid-template-columns: 1fr 1fr;
        align-items: start;
    }
}

.panel {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 20px;
}

.field-label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 6px;
}

.text-input,
.select-input {
    width: 100%;
    font-family: inherit;
    font-size: 0.95rem;
    padding: 10px 12px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--bg);
    color: var(--text);
    resize: vertical;
}

.text-input:focus,
.select-input:focus {
    outline: 2px solid var(--accent);
    outline-offset: 1px;
}

.hint {
    margin: 6px 2px 0;
    font-size: 0.78rem;
    color: var(--text-muted);
}

.field-group {
    margin-top: 18px;
}

.btn-group {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.chip {
    border: 1px solid var(--border);
    background: var(--chip-bg);
    color: var(--text);
    padding: 8px 14px;
    border-radius: 999px;
    font-size: 0.85rem;
    cursor: pointer;
}

.chip.active {
    background: var(--chip-active-bg);
    color: var(--chip-active-text);
    border-color: var(--chip-active-bg);
}

.color-row {
    display: flex;
    gap: 20px;
}

.color-field {
    flex: 1;
}

input[type="color"] {
    width: 100%;
    height: 40px;
    padding: 2px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--bg);
    cursor: pointer;
}

.preview-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.qr-stage {
    width: 100%;
    min-height: 240px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: 12px;
}

.qr-placeholder {
    color: var(--text-muted);
    font-size: 0.9rem;
    text-align: center;
    max-width: 240px;
}

.qr-canvas-wrap {
    display: none;
    max-width: 100%;
}

.qr-canvas-wrap canvas,
.qr-canvas-wrap img,
.qr-canvas-wrap svg {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

.qr-stage.has-code .qr-placeholder {
    display: none;
}

.qr-stage.has-code .qr-canvas-wrap {
    display: block;
}

.actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    width: 100%;
}

.btn {
    flex: 1 1 auto;
    min-width: 130px;
    padding: 11px 16px;
    border-radius: 8px;
    border: 1px solid transparent;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
}

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

.btn-primary {
    background: var(--accent);
    color: var(--accent-contrast);
}

.btn-primary:hover:not(:disabled) {
    background: var(--accent-hover);
}

.btn-secondary {
    background: var(--chip-bg);
    color: var(--text);
    border-color: var(--border);
}

.btn-secondary:hover:not(:disabled) {
    filter: brightness(1.05);
}

.toast {
    min-height: 20px;
    font-size: 0.82rem;
    color: var(--text-muted);
    margin: 0;
    text-align: center;
}

.toast.error {
    color: var(--danger);
}

.footer {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px 40px;
    text-align: center;
}

.footer p {
    font-size: 0.78rem;
    color: var(--text-muted);
}