#lvn-container { font-family: 'Noto Sans JP', sans-serif; max-width: 900px; margin: 20px auto; padding: 20px; border: 1px solid #ccc; border-radius: 8px; background: #f9f9f9; }
#lvn-container h1 { text-align: center; font-weight: bold; color: #333; }
#lvn-input-text { width: 100%; padding: 10px; font-size: 16px; margin-bottom: 10px; box-sizing: border-box; border-radius: 4px; border: 1px solid #ccc; }
#lvn-generate-btn, #lvn-download-btn { display: block; width: 100%; padding: 12px; font-size: 18px; cursor: pointer; background-color: #0073aa; color: white; border: none; border-radius: 4px; text-align: center; text-decoration: none; margin-top: 10px; box-sizing: border-box; }
#lvn-generate-btn:hover, #lvn-download-btn:hover { background-color: #005a87; }
#lvn-toolbar { margin-top: 20px; padding: 10px; background: #f0f0f0; border: 1px solid #ddd; border-radius: 4px; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 15px; align-items: center; }
.toolbar-section { display: flex; flex-direction: column; }
.toolbar-section label { margin-bottom: 5px; font-size: 14px; }
#lvn-toggle-lines-btn { padding: 8px 12px; cursor: pointer; background: #fff; border: 1px solid #ccc; border-radius: 4px; }
#lvn-toggle-lines-btn:hover { background: #e9e9e9; }
#lvn-preview-area { margin-top: 20px; }
#lvn-preview-content { background: #e0e0e0; padding: 20px; display: flex; flex-direction: column; align-items: center; overflow-x: auto; }
.a4-page { width: 210mm; min-height: 297mm; background: white; box-shadow: 0 0 10px rgba(0,0,0,0.1); padding: 15mm; box-sizing: border-box; display: flex; flex-direction: row-reverse; gap: 0; position: relative; overflow: hidden; }
.a4-page::after { content: "FREE JAPANESE | AhoVN.net"; position: absolute; bottom: 10mm; left: 50%; transform: translateX(-50%); font-size: 14px; color: #0000ff; opacity: 0.5; pointer-events: none; }
.writing-column { display: flex; flex-direction: column; width: 10%; height: 100%; }
.char-box { width: 100%; aspect-ratio: 1 / 1; box-sizing: border-box; display: flex; justify-content: center; align-items: center; position: relative; border: 1.5px solid #4a90e2; margin: -0.75px; opacity: 1.0; }
.char-box .dashed-line { position: absolute; background-color: transparent; transition: opacity 0.3s; }
.dashed-line.horizontal { width: 100%; height: 1px; top: 50%; left: 0; border-top: 1px dashed #aaaaaa; }
.dashed-line.vertical { width: 1px; height: 100%; left: 50%; top: 0; border-left: 1px dashed #aaaaaa; }
.char-box.hide-lines .dashed-line { opacity: 0; }
.char-box .char-content { writing-mode: vertical-rl; font-size: 48px; line-height: 1; opacity: 0.2; }
#lvn-download-controls { margin-top: 15px; }