:root{--bg: #ffffff;--bg-secondary: #f5f5f7;--bg-tertiary: #e8e8ed;--text: #1d1d1f;--text-secondary: #6e6e73;--accent: #0071e3;--accent-hover: #0077ed;--border: #d2d2d7;--toggle-bg: #e5e5e5;--toggle-knob: #ffffff;--tool-gradient-start: #f5a623;--tool-gradient-end: #e49512;--toolbar-bg: #fafafa;--sidebar-bg: #f5f5f7;--canvas-bg: #e0e0e0;--modal-backdrop: rgba(0,0,0,.4);--shadow: rgba(0,0,0,.08);--highlight: rgba(255,255,0,.35);--danger: #ff3b30;--success: #34c759}@media (prefers-color-scheme: dark){:root:not([data-theme=light]){--bg: #000000;--bg-secondary: #1c1c1e;--bg-tertiary: #2c2c2e;--text: #f5f5f7;--text-secondary: #98989d;--accent: #2997ff;--accent-hover: #40a9ff;--border: #38383a;--toggle-bg: #3a3a3c;--toggle-knob: #ffffff;--toolbar-bg: #1c1c1e;--sidebar-bg: #1c1c1e;--canvas-bg: #2c2c2e;--modal-backdrop: rgba(0,0,0,.6);--shadow: rgba(0,0,0,.3)}}[data-theme=dark]{--bg: #000000;--bg-secondary: #1c1c1e;--bg-tertiary: #2c2c2e;--text: #f5f5f7;--text-secondary: #98989d;--accent: #2997ff;--accent-hover: #40a9ff;--border: #38383a;--toggle-bg: #3a3a3c;--toggle-knob: #ffffff;--toolbar-bg: #1c1c1e;--sidebar-bg: #1c1c1e;--canvas-bg: #2c2c2e;--modal-backdrop: rgba(0,0,0,.6);--shadow: rgba(0,0,0,.3)}[data-theme=light]{--bg: #ffffff;--bg-secondary: #f5f5f7;--bg-tertiary: #e8e8ed;--text: #1d1d1f;--text-secondary: #6e6e73;--accent: #0071e3;--accent-hover: #0077ed;--border: #d2d2d7;--toggle-bg: #e5e5e5;--toggle-knob: #ffffff;--toolbar-bg: #fafafa;--sidebar-bg: #f5f5f7;--canvas-bg: #e0e0e0;--modal-backdrop: rgba(0,0,0,.4);--shadow: rgba(0,0,0,.08)}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;height:100vh;display:flex;flex-direction:column;overflow:hidden}header{display:flex;align-items:center;justify-content:space-between;padding:.5rem 1rem;background:var(--bg-secondary);border-bottom:1px solid 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var(--border);padding-top:12px}.sig-saved-label{font-size:.8rem;color:var(--text-secondary);display:block;margin-bottom:8px}.sig-saved-slots{display:flex;gap:8px}.sig-saved-slot{position:relative;width:120px;height:50px;border:1px solid var(--border);border-radius:6px;background:#fff;cursor:pointer;overflow:hidden;display:flex;align-items:center;justify-content:center;transition:border-color .15s}.sig-saved-slot:hover{border-color:var(--accent)}.sig-saved-slot.active{border-color:var(--accent);border-width:2px}.sig-saved-slot img{max-width:100%;max-height:100%}.sig-saved-slot .sig-delete{position:absolute;top:-2px;right:2px;background:none;border:none;color:var(--danger);font-size:.9rem;cursor:pointer;line-height:1}.sig-saved-slot.empty{color:var(--text-secondary);font-size:.7rem}.toast{position:fixed;bottom:24px;left:50%;transform:translate(-50%);background:var(--bg-secondary);color:var(--text);border:1px solid var(--border);padding:10px 20px;border-radius:10px;font-size:.85rem;box-shadow:0 4px 16px var(--shadow);z-index:2000;animation:toast-in .3s ease}@keyframes toast-in{0%{opacity:0;transform:translate(-50%) translateY(10px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.spinner{display:inline-block;width:18px;height:18px;border:2px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .6s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@media (max-width: 800px){.btn-label{display:none}.toolbar button{padding:5px 6px}.sidebar{width:140px}.nav-group{flex-wrap:wrap}}@media (max-width: 640px){header{padding:.4rem .75rem}.tool-name{font-size:1rem}.tool-icon{width:30px;height:30px;border-radius:6px}.tool-icon svg{width:18px;height:18px}.sidebar{position:absolute;z-index:80;height:calc(100% - var(--header-h, 48px) - var(--toolbar-h, 38px));top:auto;box-shadow:4px 0 12px var(--shadow)}.modal{max-width:100%;margin:0;border-radius:14px 14px 0 0;max-height:90vh}}