:root {
    --fallback-start: #1a1a2e;
    --fallback-mid: #16213e;
    --fallback-end: #0f3460;
    color-scheme: dark;
    --icon-opacity: 0.45;
    --panel-opacity: 0.88;
    --transition: 0.18s ease;
    --surface-base-rgb: 18, 20, 27;
    --surface-elevated-rgb: 28, 31, 40;
    --tint-rgb: 64, 70, 92;
    --stroke-rgb: 54, 61, 78;
    --on-surface-rgb: 244, 247, 251;
    --on-surface-muted-rgb: 166, 176, 193;
    --surface-base: rgb(var(--surface-base-rgb));
    --surface-elevated: rgb(var(--surface-elevated-rgb));
    --tint: rgb(var(--tint-rgb));
    --stroke: rgb(var(--stroke-rgb));
    --on-surface: rgb(var(--on-surface-rgb));
    --on-surface-muted: rgb(var(--on-surface-muted-rgb));
    --accent: rgb(var(--accent-rgb));
    --theme-surface-base-rgb: 18, 20, 27;
    --theme-surface-elevated-rgb: 28, 31, 40;
    --theme-tint-rgb: 64, 70, 92;
    --theme-stroke-rgb: 54, 61, 78;
    --theme-on-surface-rgb: 244, 247, 251;
    --theme-on-surface-muted-rgb: 166, 176, 193;
    --theme-accent-rgb: 99, 102, 241;
    --theme-accent-contrast-rgb: 255, 255, 255;
    --surface-rgb: var(--surface-base-rgb);
    --surface-soft-rgb: var(--surface-elevated-rgb);
    --surface-strong-rgb: var(--surface-base-rgb);
    --border-rgb: var(--stroke-rgb);
    --text-primary-rgb: var(--on-surface-rgb);
    --text-secondary-rgb: var(--on-surface-muted-rgb);
    --text-muted-rgb: var(--on-surface-muted-rgb);
    --glass-rgb: var(--surface-base-rgb);
    --glass-bg: rgba(var(--surface-base-rgb), var(--panel-opacity));
    --glass-tint: linear-gradient(180deg, rgba(var(--tint-rgb), 0.20), rgba(var(--surface-elevated-rgb), 0.08));
    --glass-border: 1px solid rgba(var(--stroke-rgb), 0.72);
    --glass-shadow: 0 24px 70px rgba(0, 0, 0, 0.55);
    --glass-highlight: 0 1px 0 rgba(var(--on-surface-rgb), 0.05) inset;
    --text-primary: rgba(var(--on-surface-rgb), 0.94);
    --text-secondary: rgba(var(--on-surface-muted-rgb), 0.78);
    --text-muted: rgba(var(--on-surface-muted-rgb), 0.58);
    --accent-rgb: 99, 102, 241;
    --accent-contrast-rgb: 255, 255, 255;
    --divider: rgba(var(--stroke-rgb), 0.70);
    --control-bg: rgba(var(--surface-elevated-rgb), 0.58);
    --control-bg-hover: rgba(var(--tint-rgb), 0.34);
    --control-border: rgba(var(--stroke-rgb), 0.74);
    --control-border-hover: rgba(var(--stroke-rgb), 0.98);
    --field-bg: rgba(var(--surface-base-rgb), 0.42);
    --field-bg-hover: rgba(var(--surface-elevated-rgb), 0.72);
    --accent-soft: rgba(var(--accent-rgb), 0.14);
    --accent-border: rgba(var(--accent-rgb), 0.32);
    --settings-panel-bg:
        linear-gradient(180deg, rgba(var(--on-surface-rgb), 0.045), rgba(var(--tint-rgb), 0.040) 38%, transparent),
        color-mix(in srgb, rgba(var(--surface-base-rgb), var(--panel-opacity)) 72%, rgba(18, 20, 27, var(--panel-opacity)));
    --settings-shell-bg:
        linear-gradient(180deg, rgba(var(--on-surface-rgb), 0.065), rgba(var(--tint-rgb), 0.045) 36%, transparent),
        color-mix(in srgb, rgba(var(--surface-base-rgb), var(--panel-opacity)) 70%, rgba(18, 20, 27, var(--panel-opacity)));
    --settings-sidebar-bg:
        linear-gradient(180deg, rgba(var(--on-surface-rgb), 0.050), rgba(var(--tint-rgb), 0.065)),
        color-mix(in srgb, rgba(var(--surface-base-rgb), 0.90) 64%, rgba(18, 20, 27, 0.90));
    --settings-content-bg:
        linear-gradient(180deg, rgba(var(--tint-rgb), 0.038), transparent 44%),
        color-mix(in srgb, rgba(var(--surface-elevated-rgb), 0.88) 72%, rgba(28, 31, 40, 0.88));
    --settings-section-bg:
        linear-gradient(180deg, rgba(var(--on-surface-rgb), 0.035), transparent),
        color-mix(in srgb, rgba(var(--surface-base-rgb), 0.18) 68%, rgba(18, 20, 27, 0.18));
    --settings-section-header-bg:
        linear-gradient(180deg, rgba(var(--on-surface-rgb), 0.038), transparent),
        color-mix(in srgb, rgba(var(--surface-elevated-rgb), 0.14) 70%, rgba(28, 31, 40, 0.14));
    --settings-row-bg: transparent;
    --settings-row-hover-bg: rgba(var(--tint-rgb), 0.070);
    --settings-row-selected-bg:
        linear-gradient(90deg, rgba(var(--accent-rgb), 0.070), transparent 66%),
        color-mix(in srgb, rgba(var(--surface-base-rgb), 0.24) 62%, rgba(18, 20, 27, 0.24));
    --settings-field-bg: color-mix(in srgb, rgba(var(--surface-base-rgb), 0.24) 62%, rgba(18, 20, 27, 0.24));
    --settings-field-bg-hover: color-mix(in srgb, rgba(var(--surface-base-rgb), 0.34) 66%, rgba(28, 31, 40, 0.34));
    --settings-field-bg-focus: color-mix(in srgb, rgba(var(--surface-base-rgb), 0.38) 68%, rgba(28, 31, 40, 0.38));
    --settings-border-subtle: color-mix(in srgb, rgba(var(--stroke-rgb), 0.34) 74%, rgba(54, 61, 78, 0.34));
    --settings-border: color-mix(in srgb, rgba(var(--stroke-rgb), 0.52) 76%, rgba(54, 61, 78, 0.52));
    --settings-border-strong: color-mix(in srgb, rgba(var(--stroke-rgb), 0.74) 78%, rgba(54, 61, 78, 0.74));
    --settings-accent-soft: rgba(var(--accent-rgb), 0.12);
    --settings-accent-muted: rgba(var(--accent-rgb), 0.24);
    --settings-accent-rail: rgba(var(--accent-rgb), 0.62);
    --settings-focus-ring: 0 0 0 3px rgba(var(--accent-rgb), 0.14);
    --settings-shadow: 0 24px 70px rgba(0, 0, 0, 0.42);
    --settings-inset-highlight: 0 1px 0 rgba(var(--on-surface-rgb), 0.055) inset;
    --danger-rgb: 220, 53, 69;
    --success-rgb: 46, 204, 113;
    --warning-rgb: 255, 152, 0;
    --icon-bg: #3e3e44;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --press-scale: 0.97;
}

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

:focus-visible {
    outline: 2px solid rgba(var(--accent-rgb), 0.7);
    outline-offset: 2px;
}

html {
    background-color: #2a2a2e;
}

body {
    width: 100vw;
    height: 100vh;
    background: linear-gradient(180deg, var(--fallback-start) 0%, var(--fallback-mid) 50%, var(--fallback-end) 100%);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    font-size: var(--app-font-size, 16px);
    overflow: hidden;
}

.wp-mode-chip,
.lang-title,
.lang-option,
.onboarding-body,
.onboarding-action {
    font-size: calc(13px * var(--app-font-scale, 1)) !important;
}

.onboarding-title {
    font-size: calc(20px * var(--app-font-scale, 1)) !important;
}

html[data-reduced-motion="true"] *,
html[data-reduced-motion="true"] *::before,
html[data-reduced-motion="true"] *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
}

/* ========== 右上角按钮 ========== */
.corner-btn {
    position: fixed;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 100;
    background: var(--glass-tint), var(--glass-bg);
    border: var(--glass-border);
    transition: opacity var(--transition), background var(--transition), transform var(--transition), border-color var(--transition);
    -webkit-tap-highlight-color: transparent;
    user-select: none;
    color: inherit;
}

.corner-btn svg {
    width: 18px;
    height: 18px;
    fill: var(--text-primary);
    pointer-events: none;
}

.lang-btn {
    top: 22px;
    right: 76px;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition), visibility 0s linear var(--transition), background var(--transition), transform var(--transition);
}

.lang-btn.visible,
.lang-btn:hover {
    opacity: 1;
    visibility: visible;
    transition: opacity var(--transition), visibility 0s linear 0s, background var(--transition), transform var(--transition);
}

.settings-btn {
    top: 22px;
    right: 22px;
    opacity: var(--icon-opacity);
}

.settings-btn.visible,
.settings-btn:hover {
    opacity: 1;
    background: var(--control-bg-hover);
    border-color: var(--control-border-hover);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.35);
}

.settings-btn:hover {
    transform: rotate(30deg);
}

.settings-btn.panel-open {
    opacity: 1;
    background: var(--control-bg-hover);
    border-color: var(--accent-border);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
    transform: rotate(60deg);
}

.lang-btn:hover {
    transform: scale(1.05);
}

.lang-btn:active {
    transform: scale(var(--press-scale));
    transition: transform 0.12s ease;
}

.settings-btn:active {
    transform: rotate(30deg) scale(0.92);
    transition: transform 0.12s ease;
}

/* ========== 语言面板 ========== */
.language-panel {
    position: fixed;
    top: 78px;
    right: 76px;
    background: var(--glass-tint), var(--glass-bg);
    border-radius: var(--radius-lg);
    contain: paint;
    padding: 8px 0;
    min-width: 170px;
    box-shadow: var(--glass-shadow), var(--glass-highlight);
    border: var(--glass-border);
    z-index: 99;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity 0.18s ease, transform 0.18s cubic-bezier(0.2, 0.8, 0.2, 1);
    user-select: none;
}

.language-panel.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.cmd-palette-overlay {
    position: fixed;
    inset: 0;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.lang-title {
    color: var(--text-secondary);
    font-size: 12px;
    font-weight: 600;
    text-align: left;
    margin-bottom: 6px;
    padding: 0 18px 8px;
    letter-spacing: -0.01em;
    border-bottom: 1px solid var(--divider);
}

.lang-option {
    display: block;
    width: 100%;
    padding: 9px 18px;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 13px;
    text-align: left;
    cursor: pointer;
    transition: background 0.12s ease;
    font-family: inherit;
    letter-spacing: -0.01em;
}

.lang-option:hover {
    background: var(--control-bg);
    color: var(--text-primary);
}

.lang-option.current {
    color: var(--text-primary);
    font-weight: 600;
    background: var(--accent-soft);
}

/* ========== 首次使用提示 ========== */
.onboarding-hint {
    position: fixed;
    left: 24px;
    bottom: 24px;
    z-index: 90;
    width: min(390px, calc(100vw - 48px));
    padding: 16px 18px 14px;
    color: var(--text-primary);
    background: var(--glass-tint), var(--glass-bg);
    border: var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow), var(--glass-highlight);
    opacity: 0;
    visibility: hidden;
    transform: translateY(14px);
    transition: opacity 0.55s ease, transform 0.55s cubic-bezier(0.2, 0.8, 0.2, 1), visibility 0s linear 0.55s;
    user-select: none;
}

.onboarding-hint.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    transition: opacity 0.55s ease, transform 0.55s cubic-bezier(0.2, 0.8, 0.2, 1), visibility 0s linear 0s;
}

.onboarding-close {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 28px;
    height: 28px;
    border: none;
    border-radius: 50%;
    color: var(--text-muted);
    background: transparent;
    cursor: pointer;
    font-size: 20px;
    line-height: 1;
    font-family: inherit;
    transition: color var(--transition), background var(--transition);
}

.onboarding-close:hover {
    color: var(--text-primary);
    background: var(--control-bg);
}

.onboarding-title {
    padding-right: 28px;
    font-size: 14px;
    font-weight: 700;
}

.onboarding-body {
    margin-top: 8px;
    color: var(--text-secondary);
    font-size: 13px;
    line-height: 1.55;
}

.onboarding-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 14px;
}

.onboarding-action {
    min-height: 32px;
    padding: 0 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--control-border);
    color: var(--text-secondary);
    background: var(--control-bg);
    cursor: pointer;
    font-size: 12px;
    font-family: inherit;
    transition: color var(--transition), background var(--transition), border-color var(--transition), transform var(--transition);
}

.onboarding-action:hover {
    color: var(--text-primary);
    background: var(--control-bg-hover);
    border-color: var(--control-border-hover);
}

.onboarding-action:active {
    transform: scale(var(--press-scale));
}

.onboarding-action.primary {
    color: rgb(var(--accent-contrast-rgb));
    background: rgba(var(--accent-rgb), 0.85);
    border-color: rgba(var(--accent-rgb), 0.92);
}

@media (prefers-reduced-motion: reduce) {
    .onboarding-hint,
    .onboarding-hint.visible {
        transition: opacity 0.2s ease, visibility 0s linear 0s;
        transform: none;
    }
}

/* ========== 响应式 ========== */
@media (max-width: 480px) {
    .lang-btn {
        top: 16px;
        right: 64px;
        width: 40px;
        height: 40px;
    }

    .settings-btn {
        top: 16px;
        right: 16px;
        width: 40px;
        height: 40px;
    }

    .settings-panel {
        top: 66px;
        right: 10px;
        min-width: 230px;
        padding: 18px 16px 14px;
    }

    .language-panel {
        top: 66px;
        right: 64px;
    }

    .search-bar {
        width: 90vw;
    }

    .onboarding-hint {
        left: 12px;
        right: 12px;
        bottom: 12px;
        width: auto;
    }
}