/* Theme previews are shared by all six themes; the original palettes live in styles.css. */
.theme-buttons {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 10px;
}

.theme-buttons .theme-btn {
    position: relative;
    min-width: 0;
    padding: 10px;
    text-align: left;
    border-radius: 9px;
    transition: background 160ms ease, border-color 160ms ease;
}

.theme-btn::before {
    content: '';
    display: block;
    height: 32px;
    margin-bottom: 10px;
    border-radius: 4px;
    box-shadow: inset 0 0 0 1px rgb(128 128 128 / 25%);
    background: var(--theme-preview);
}

.theme-btn[data-theme="default"] { --theme-preview: linear-gradient(110deg, #667eea 0% 38%, #fff 38% 78%, #764ba2 78%); }
.theme-btn[data-theme="dark"] { --theme-preview: linear-gradient(110deg, #1e1f22 0% 38%, #313438 38% 78%, #4e9fe5 78%); }
.theme-btn[data-theme="japanese"] { --theme-preview: linear-gradient(110deg, #1a0a0a 0% 38%, #f5ecd7 38% 78%, #c0392b 78%); }
.theme-btn[data-theme="sumi"] { --theme-preview: linear-gradient(110deg, #141719 0% 38%, #292e31 38% 78%, #f08070 78%); }
.theme-btn[data-theme="shiro"] { --theme-preview: linear-gradient(110deg, #ebe9e2 0% 38%, #fffefa 38% 78%, #303b38 78%); }
.theme-btn[data-theme="aizome"] { --theme-preview: linear-gradient(110deg, #101c2c 0% 38%, #21364c 38% 78%, #d8b879 78%); }

.theme-label,
.theme-description {
    display: block;
}

.theme-label {
    font-size: 13px;
    line-height: 1.4;
}

.theme-description {
    margin-top: 3px;
    font-size: 11px;
    font-weight: 400;
    line-height: 1.5;
}

.theme-buttons .theme-btn.active {
    outline: 1px solid currentColor;
    outline-offset: -5px;
}

.theme-buttons .theme-btn:focus-visible {
    outline: 3px solid currentColor;
    outline-offset: 3px;
}

/* Sumi: ink, brushed charcoal and a restrained vermilion accent. */
body.theme-sumi {
    color-scheme: dark;
    --theme-bg: #101214;
    --theme-surface: #191d20;
    --theme-panel: #202528;
    --theme-inset: #141719;
    --theme-hover: #2c3337;
    --theme-border: #394247;
    --theme-text: #f0f1ed;
    --theme-muted: #adb5b7;
    --theme-accent: #f08070;
    --theme-accent-hover: #ff9b8d;
    --theme-accent-soft: #392824;
    --theme-on-accent: #201310;
    --theme-shadow: 0 20px 60px rgb(0 0 0 / 24%);
    --theme-success: #9ad9b0;
    --theme-success-bg: #1c3428;
    --theme-danger: #ffb1aa;
    --theme-danger-bg: #3d2327;
}

/* Shiro: a light training space, with chalk surfaces and charcoal details. */
body.theme-shiro {
    color-scheme: light;
    --theme-bg: #ebe9e2;
    --theme-surface: #faf9f5;
    --theme-panel: #fffefa;
    --theme-inset: #f1f0e9;
    --theme-hover: #e8ece6;
    --theme-border: #d4d8cd;
    --theme-text: #222d29;
    --theme-muted: #5d6962;
    --theme-accent: #303b38;
    --theme-accent-hover: #465c50;
    --theme-accent-soft: #e2e9df;
    --theme-on-accent: #fffefa;
    --theme-shadow: 0 20px 60px rgb(40 50 39 / 8%);
    --theme-success: #25613c;
    --theme-success-bg: #e4efe4;
    --theme-danger: #a13832;
    --theme-danger-bg: #f8e7e3;
}

/* Aizome: an indigo uniform palette with muted brass details. */
body.theme-aizome {
    color-scheme: dark;
    --theme-bg: #0b1421;
    --theme-surface: #101c2c;
    --theme-panel: #17283c;
    --theme-inset: #0d1827;
    --theme-hover: #21364c;
    --theme-border: #354b60;
    --theme-text: #edf2f5;
    --theme-muted: #acbfce;
    --theme-accent: #d8b879;
    --theme-accent-hover: #edcf98;
    --theme-accent-soft: #30342f;
    --theme-on-accent: #172131;
    --theme-shadow: 0 20px 60px rgb(0 0 0 / 25%);
    --theme-success: #9ed5bd;
    --theme-success-bg: #16382f;
    --theme-danger: #ffb1aa;
    --theme-danger-bg: #3a2938;
}

/* Shared component rules keep every modern palette consistent. */
body.theme-modern {
    background: var(--theme-bg);
    color: var(--theme-text);
    font-family: 'Segoe UI', system-ui, sans-serif;
    padding: 24px;
    -webkit-font-smoothing: antialiased;
}

body.theme-modern button,
body.theme-modern input {
    font-family: inherit;
}

body.theme-modern :is(button, a, input, [tabindex]):focus-visible {
    outline: 2px solid var(--theme-accent);
    outline-offset: 3px;
}

body.theme-modern ::selection {
    background: var(--theme-accent);
    color: var(--theme-on-accent);
}

body.theme-modern .app-container {
    background: var(--theme-surface);
    border: 1px solid var(--theme-border);
    border-radius: 16px;
    box-shadow: var(--theme-shadow);
    gap: 0;
}

body.theme-modern .compendium-content {
    padding: 32px;
    min-width: 0;
}

body.theme-modern .compendium-header {
    margin-bottom: 28px;
    padding-right: 48px;
}

body.theme-modern .compendium-container h1 {
    display: flex;
    align-items: center;
    gap: 14px;
    color: var(--theme-text);
    font-size: 30px;
    font-weight: 650;
    letter-spacing: -0.035em;
    line-height: 1.25;
    margin-bottom: 0;
}

body.theme-modern .compendium-container h1::before {
    content: '';
    width: 4px;
    height: 26px;
    border-radius: 2px;
    background: var(--theme-accent);
    flex-shrink: 0;
}

body.theme-modern .hamburger-btn {
    padding: 12px;
    border: 1px solid var(--theme-border);
    border-radius: 10px;
    background: var(--theme-panel);
}

body.theme-modern .hamburger-btn span {
    background: var(--theme-text);
    width: 22px;
    height: 2px;
}

body.theme-modern .hamburger-btn.active span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
body.theme-modern .hamburger-btn.active span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

body.theme-modern :is(.hamburger-dropdown, .settings-panel, .license-panel, .technique-detail-modal) {
    background: var(--theme-panel);
    color: var(--theme-text);
    border: 1px solid var(--theme-border);
    box-shadow: var(--theme-shadow);
    border-radius: 14px;
}

body.theme-modern :is(.menu-item, .compendium-menu-item, .compendium-submenu-item, .compendium-search-result-btn) {
    background: transparent;
    color: var(--theme-text);
}

body.theme-modern :is(.menu-item, .compendium-menu-item, .compendium-submenu-item, .compendium-search-result-btn):hover {
    background: var(--theme-hover);
    color: var(--theme-text);
    border-color: transparent;
}

body.theme-modern :is(.menu-item, .compendium-menu-item, .compendium-submenu-item).active {
    background: var(--theme-accent-soft);
    color: var(--theme-accent);
    border-color: transparent;
    box-shadow: inset 3px 0 var(--theme-accent);
}

body.theme-modern .compendium-menu {
    background: var(--theme-panel);
    border-color: var(--theme-border);
    border-radius: 12px;
    flex-shrink: 0;
}

body.theme-modern .compendium-menu-toggle {
    background: var(--theme-inset);
    color: var(--theme-text);
    border-bottom: 1px solid var(--theme-border);
    padding: 16px 14px;
}

body.theme-modern .compendium-menu-toggle:hover {
    background: var(--theme-hover);
}

body.theme-modern :is(.compendium-menu-item, .compendium-submenu-item) {
    border-radius: 6px;
    font-weight: 500;
    line-height: 1.5;
}

body.theme-modern .compendium-submenu { border-color: var(--theme-border); }
body.theme-modern .compendium-search { border-color: var(--theme-border); }

body.theme-modern :is(.compendium-search-input, .compendium-search-results) {
    background: var(--theme-inset);
    color: var(--theme-text);
    border-color: var(--theme-border);
}

body.theme-modern .compendium-search-input::placeholder { color: var(--theme-muted); }
body.theme-modern .compendium-search-button { color: var(--theme-muted); }

body.theme-modern .compendium-search-button:hover { color: var(--theme-text); }

body.theme-modern :is(.compendium-search-input:focus, .compendium-search-button:focus-visible) {
    outline-color: var(--theme-accent);
}

body.theme-modern .compendium-content-area {
    min-width: 0;
    width: 100%;
}

body.theme-modern .compendium-techniques {
    margin-top: 0;
    gap: 18px;
}

body.theme-modern .technique-card {
    background: var(--theme-panel);
    border: 1px solid var(--theme-border);
    border-radius: 10px;
    box-shadow: none;
    transition: transform 160ms ease, border-color 160ms ease;
}

body.theme-modern .technique-card:hover {
    transform: translateY(-3px);
    border-color: var(--theme-accent);
    box-shadow: none;
}

/* Preserve the original instructional images without tinting or inversion. */
body.theme-modern .technique-card-image { background: #f5f5f2; }

body.theme-modern .technique-card-name {
    background: var(--theme-panel);
    color: var(--theme-text);
    border-top: 1px solid var(--theme-border);
    text-align: left;
    font-size: 14px;
    font-weight: 500;
    line-height: 1.45;
    padding: 13px 14px;
}

body.theme-modern :is(.settings-overlay, .license-overlay, .technique-detail-overlay) {
    background: rgb(5 12 16 / 65%);
}

body.theme-modern :is(.settings-header, .license-header) {
    border-color: var(--theme-border);
    background: var(--theme-panel);
}

body.theme-modern .flashcard-settings,
body.theme-modern .flashcard-settings[open] summary {
    border-color: var(--theme-border);
}

body.theme-modern .flashcard-settings summary {
    color: var(--theme-text);
}

body.theme-modern .flashcard-settings summary:hover {
    background: var(--theme-hover);
}

body.theme-modern .flashcard-settings summary:focus-visible {
    outline-color: var(--theme-accent);
}

body.theme-modern :is(.settings-header h2, .license-header h2, .settings-content h3, .stats h3, .sidebar h2, .detail-section-title, #detail-technique-name) {
    color: var(--theme-text);
}

body.theme-modern :is(.settings-description, .category-group-title, .instruction, .stats p, .kanji-item span, .extra-image-caption, .compendium-search-no-results, .compendium-container p) {
    color: var(--theme-muted);
}

body.theme-modern .settings-header h2 { font-size: 20px; }
body.theme-modern .settings-content h3 { font-size: 14px; }

body.theme-modern :is(.close-btn, .technique-detail-modal .close-btn, .technique-detail-modal .share-btn) {
    background: var(--theme-inset);
    color: var(--theme-text);
    border-radius: 8px;
}

body.theme-modern :is(.close-btn, .technique-detail-modal .close-btn, .technique-detail-modal .share-btn):hover {
    background: var(--theme-hover);
    color: var(--theme-accent);
}

body.theme-modern :is(.category-btn, .lang-btn, .theme-btn) {
    background: var(--theme-inset);
    border-color: var(--theme-border);
    color: var(--theme-text);
}

body.theme-modern :is(.category-btn, .lang-btn, .theme-btn):hover:not(.active) {
    background: var(--theme-hover);
    border-color: var(--theme-accent);
}

body.theme-modern :is(.category-btn, .lang-btn, .theme-btn).active {
    background: var(--theme-accent-soft);
    color: var(--theme-accent);
    border-color: var(--theme-accent);
}

body.theme-modern .theme-description { color: var(--theme-muted); }

/* Belt borders retain their syllabus colors, including when selected. */
body.theme-modern .belt-btn:not(.active) {
    background: var(--theme-inset);
    color: var(--theme-text);
}

body.theme-modern .belt-btn.active:is([data-kyu="5_kyu_gelb"], [data-kyu="4_kyu_orange"]) { color: #241b0b; }
body.theme-modern .belt-btn.active[data-kyu="3_kyu_gruen"] { background: #1d751d; }

body.theme-modern .sidebar {
    background: var(--theme-inset);
    border-color: var(--theme-border);
}

body.theme-modern :is(.stats, .words-section, .kanji-breakdown) {
    background: var(--theme-panel);
    border: 1px solid var(--theme-border);
    border-radius: 10px;
}

body.theme-modern .stats span { color: var(--theme-text); }
body.theme-modern .kanji-breakdown { border-left: 3px solid var(--theme-accent); }
body.theme-modern .kanji-item strong { color: var(--theme-accent); }
body.theme-modern :is(.technique-description, .detail-extra-text, .license-content) { color: var(--theme-text); }
body.theme-modern :is(.detail-extra, .detail-extra-block-spaced) { border-color: var(--theme-border); }
body.theme-modern :is(.license-content a, .detail-extra a) { color: var(--theme-accent); }
body.theme-modern #technique-image { box-shadow: none; border-radius: 10px; }

body.theme-modern .answer-placeholder {
    background: var(--theme-inset);
    color: var(--theme-muted);
    border-color: var(--theme-border);
}

body.theme-modern .answer-placeholder.filled {
    background: var(--theme-accent-soft);
    color: var(--theme-accent);
    border-color: var(--theme-accent);
}

body.theme-modern :is(.word-btn, .btn-show) {
    background: var(--theme-accent);
    color: var(--theme-on-accent);
    border-radius: 6px;
    box-shadow: none;
}

body.theme-modern :is(.word-btn, .btn-show):hover {
    background: var(--theme-accent-hover);
    box-shadow: none;
}

body.theme-modern .word-btn.selected {
    background: var(--theme-hover);
    color: var(--theme-muted);
    opacity: 0.65;
    transform: none;
}

body.theme-modern .btn-skip {
    background: var(--theme-hover);
    color: var(--theme-text);
}

body.theme-modern .btn-skip:hover { background: var(--theme-border); }
body.theme-modern #reset-stats { background: var(--theme-danger-bg); color: var(--theme-danger); }
body.theme-modern #reset-stats:hover { box-shadow: inset 0 0 0 1px var(--theme-danger); }

body.theme-modern :is(.feedback, .answer-placeholder).correct {
    background: var(--theme-success-bg);
    color: var(--theme-success);
    border-color: var(--theme-success);
}

body.theme-modern :is(.feedback, .answer-placeholder).incorrect {
    background: var(--theme-danger-bg);
    color: var(--theme-danger);
    border-color: var(--theme-danger);
}

body.theme-modern .progress-bar { background: var(--theme-border); height: 5px; }
body.theme-modern .progress-fill { background: var(--theme-accent); }
body.theme-modern .footer-credits-btn { color: var(--theme-muted); }
body.theme-modern .footer-support-btn { color: var(--theme-accent); }
body.theme-modern .footer-credits-btn:hover { color: var(--theme-text); }
body.theme-modern .share-toast { background: var(--theme-accent); color: var(--theme-on-accent); }

@media (max-width: 768px) {
    body.theme-modern { padding: 12px; }
    body.theme-modern .app-container { border-radius: 12px; padding-top: 72px; }
    body.theme-modern .compendium-content { padding: 0 16px 20px; }
    body.theme-modern .compendium-header { margin-bottom: 0; }
    body.theme-modern .compendium-container h1 { top: 21px; font-size: 26px; }
    body.theme-modern .hamburger-menu { top: 14px; right: 14px; }
    body.theme-modern .compendium-layout { gap: 18px; }
    body.theme-modern .compendium-menu { min-width: 0; }
    body.theme-modern .compendium-techniques { gap: 12px; }
    body.theme-modern .technique-card-name { padding: 11px; font-size: 13px; }
    body.theme-modern .main-content { min-width: 0; padding: 16px; }
}

@media (max-width: 480px) {
    .theme-buttons { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (prefers-reduced-motion: reduce) {
    body.theme-modern *,
    body.theme-modern *::before,
    body.theme-modern *::after,
    .theme-buttons .theme-btn {
        animation: none;
        transition: none;
    }
    body.theme-modern :is(.technique-card, .word-btn):hover { transform: none; }
}