:root {
    --primary: #2563eb;
    --bg: #ffffff;
    --surface: #f8fafc;
    --border: #e2e8f0;
    --text-main: #0f172a;
    --text-sub: #64748b;
    --header-border: #000000;
    --btn-bg: #0f172a;
    --btn-text: #ffffff;
}

body.dark-mode {
    --bg: #0f172a;
    --surface: #1e293b;
    --border: #334155;
    --text-main: #f1f5f9;
    --text-sub: #94a3b8;
    --header-border: #f1f5f9;
    --btn-bg: #1e293b;
    --btn-text: #f1f5f9;
}

body {
    background-color: var(--bg);
    font-family: var(--app-font, 'Zen Maru Gothic', sans-serif);
    color: var(--text-main);
    letter-spacing: 0.02em;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.ymm4-preview-area {
    background-color: #1e293b;
    color: #f0f0f0 !important;
    min-height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    padding: 2rem;
    text-align: center;
    line-height: 2.5;
    letter-spacing: 0.1em;
    border: 2px solid var(--header-border);
    position: relative;
    overflow: hidden;
    user-select: none;
}

#previewText {
    color: #f0f0f0;
}

.placeholder-text {
    color: #94a3b8 !important;
    font-size: 1.25rem;
    opacity: 0.7;
    letter-spacing: normal;
}

#rubyWarning {
    position: absolute;
    bottom: 8px;
    right: 12px;
    font-size: 10px;
    color: #ef4444;
    font-weight: bold;
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
    letter-spacing: normal;
}

#rubyWarning.visible {
    opacity: 1;
}

textarea {
    border: 1px solid var(--border);
    border-radius: 0;
    background-color: var(--surface);
    transition: all 0.2s ease;
    font-family: inherit;
    color: var(--text-main);
    resize: none;
}

textarea:focus {
    outline: none;
    border-color: var(--primary);
    background-color: var(--bg);
}

.copy-glow {
    border-color: #10b981 !important;
    box-shadow: 0 0 0 4px rgba(16, 185, 129, 0.4);
}

button {
    border-radius: 0;
    transition: all 0.2s ease;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 700;
}

.btn-primary {
    background-color: var(--btn-bg);
    color: var(--btn-text);
    border: 1px solid var(--border);
}

.btn-primary:hover {
    opacity: 0.85;
}

.btn-outline {
    border: 1px solid var(--border);
    background-color: var(--surface);
    color: var(--text-sub);
}

.btn-outline:hover {
    border-color: var(--text-main);
    color: var(--text-main);
    background-color: rgba(0, 0, 0, 0.05);
}

body.dark-mode .btn-outline:hover {
    background-color: rgba(255, 255, 255, 0.05);
}

.btn-copy {
    background-color: #10b981;
    color: white;
}

ruby {
    ruby-align: center;
    color: #f0f0f0;
    cursor: pointer;
    padding: 2px 2px;
    transition: all 0.2s;
    position: relative;
    display: inline-flex;
    flex-direction: column-reverse;
    align-items: center;
    vertical-align: bottom;
    transform: translateY(2px);
}

ruby:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

rt {
    display: block;
    font-size: 0.5em;
    color: #fde047;
    font-weight: 700;
    line-height: 1;
    pointer-events: none;
    letter-spacing: normal;
    position: relative;
    transform: translate(0, 0);
    margin-bottom: -0.9em;
}

rt.missing-ruby {
    color: #ef4444;
    font-size: 0.3em;
    margin-bottom: -1.2em;
    opacity: 0.8;
}

ruby[data-reading="/"] rt {
    display: none;
}

.merge-mode-active ruby.selected-for-merge {
    background-color: #2563eb !important;
    box-shadow: 0 0 0 2px #fff;
    z-index: 10;
}

.btn-merge-primary {
    background-color: #2563eb;
    color: #fff;
}
.btn-merge-primary:hover {
    background-color: #1d4ed8;
}
.btn-merge-primary:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.btn-merge-cancel {
    background-color: #64748b;
    color: #fff;
}
.btn-merge-cancel:hover {
    background-color: #475569;
}

.edit-popup {
    position: absolute;
    background: #ffffff;
    border: 1px solid #000;
    padding: 12px;
    z-index: 100;
    display: flex;
    flex-direction: column;
    gap: 8px;
    box-shadow: 6px 6px 0px #000;
    letter-spacing: normal;
    min-width: 240px;
}

body.dark-mode .edit-popup {
    background: #1e293b;
    border-color: #f1f5f9;
    box-shadow: 6px 6px 0px #f1f5f9;
}

.edit-popup label {
    font-size: 10px;
    font-weight: bold;
    color: #666;
    margin-bottom: -4px;
}

body.dark-mode .edit-popup label {
    color: #94a3b8;
}

.modal-content #dictList {
    max-height: 260px; /* だいたい5件分 */
    overflow-y: auto;
    padding-right: 6px;
}

.modal-content #dictList::-webkit-scrollbar {
    width: 10px;
}
.modal-content #dictList::-webkit-scrollbar-thumb {
    background: rgba(100, 116, 139, 0.5);
    border-radius: 999px;
}
.modal-content #dictList::-webkit-scrollbar-track {
    background: transparent;
}

.edit-popup input {
    color: #000;
    font-size: 0.875rem;
    padding: 4px 8px;
    border: 1px solid #ccc;
    width: 100%;
}

body.dark-mode .edit-popup input {
    background: #0f172a;
    color: #fff;
    border-color: #334155;
}

.edit-popup .popup-footer {
    display: flex;
    gap: 4px;
    margin-top: 4px;
}

.edit-popup button {
    flex: 1;
    font-size: 0.75rem;
    padding: 6px;
    background: #000;
    color: #fff;
}

body.dark-mode .edit-popup button {
    background: #f1f5f9;
    color: #0f172a;
}

.edit-popup .btn-popup-cancel {
    background: transparent !important;
    color: inherit !important;
    border: 1px solid var(--border) !important;
}

.edit-popup .btn-popup-cancel:hover {
    background: rgba(0, 0, 0, 0.05) !important;
}

body.dark-mode .edit-popup .btn-popup-cancel:hover {
    background: rgba(255, 255, 255, 0.05) !important;
}

.btn-slash {
    background: #f1f5f9 !important;
    color: #0f172a !important;
    border: 1px solid #cbd5e1 !important;
    width: 32px !important;
    flex: none !important;
    font-weight: bold;
}

.btn-danger-action {
    background: #ef4444 !important;
    color: white !important;
    border: none !important;
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 200;
    backdrop-filter: blur(4px);
    opacity: 0;
    transition: opacity 0.5s ease;
    padding: 24px;
}

.modal-overlay.active {
    display: flex;
    opacity: 1;
}

.modal-content {
    background: var(--bg);
    padding: 2.5rem;
    max-width: 500px;
    width: 90%;
    border: 2px solid var(--text-main);
    box-shadow: 8px 8px 0px var(--text-main);
    color: var(--text-main);
    max-height: calc(100vh - 48px);
    overflow: auto;
}

.help-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 12px;
}
.help-tabs button {
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-main);
    padding: 6px 10px;
    font-size: 10px;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}
.help-tabs button.active {
    border-color: var(--text-main);
    background: var(--text-main);
    color: var(--bg);
}

.help-slides {
    margin-top: 8px;
}
.help-slide {
    display: none;
}
.help-slide.active {
    display: block;
}

.help-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-top: 14px;
}
.help-page {
    flex: 1;
    text-align: center;
    letter-spacing: 0.12em;
}

.top-nav {
    position: fixed;
    top: 1.5rem;
    right: 1.5rem;
    display: flex;
    gap: 0.5rem;
    z-index: 50;
}

.nav-btn {
    width: 2.5rem;
    height: 2.5rem;
    border: 2px solid var(--text-main);
    background-color: var(--bg);
    color: var(--text-main);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.nav-btn.active-mode {
    background-color: var(--primary) !important;
    color: white !important;
    border-color: var(--primary) !important;
}

.nav-btn:hover {
    opacity: 0.8;
}

.sun-icon {
    display: none;
}

.moon-icon {
    display: block;
}

body.dark-mode {
    transition: none;
}

body.dark-mode .sun-icon {
    display: block;
}

body.dark-mode .moon-icon {
    display: none;
}

#setupMessage {
    border-left: 4px solid var(--primary);
    background-color: var(--surface);
}