*{margin:0;padding:0;box-sizing:border-box}:root{--font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", sans-serif;--font-canvas: "Inter", sans-serif;--font-size-base: 1rem;--font-size-small: .85rem;--font-size-tiny: .75rem;--font-weight-normal: 400;--font-weight-medium: 500;--font-weight-bold: 600;--line-height: 1.5;--page-bg: #ffffff;--surface-color: #ffffff;--surface-muted: #fafafa;--border-color: #e0e0e0;--border-radius: 8px;--border-radius-small: 4px;--shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, .1), 0 1px 2px 0 rgba(0, 0, 0, .06);--shadow-md: 0 4px 6px -1px rgba(0, 0, 0, .1), 0 2px 4px -1px rgba(0, 0, 0, .06);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .1), 0 4px 6px -2px rgba(0, 0, 0, .05);--text-primary: #212121;--text-secondary: #757575;--title-color: #212121;--title-size: 2rem;--section-label-color: #757575;--primary-color: #646ef6;--primary-hover: #3b47ef;--accent-color: #ff9800;--focus-ring: 0 0 0 3px rgba(100, 110, 246, .35);--button-bg: var(--primary-color);--button-fg: #ffffff;--button-hover-bg: var(--primary-hover);--button-radius: var(--border-radius);--button-secondary-bg: var(--surface-muted);--button-secondary-fg: var(--text-secondary);--slider-track: #e0e0e0;--slider-track-height: 6px;--slider-thumb: var(--primary-color);--slider-thumb-border: #ffffff;--slider-thumb-size: 20px;--input-bg: var(--surface-color);--input-border: var(--border-color);--value-bg: var(--surface-muted);--tooltip-bg: #212121;--tooltip-fg: #ffffff;--backdrop: rgba(33, 33, 33, .35);--secondary-color: var(--text-secondary);--background-color: var(--surface-muted);--transition: all .2s ease-in-out;--soil: #a8551f;--soil-edge: #6b3512;--soil-light: #d9b48f;--soil-layer-1: #b5651d;--soil-layer-2: #9c7a4e;--soil-layer-3: #836048;--water: #29a3e3;--water-dark: #0b6ea8;--water-light: rgba(41, 163, 227, .22);--air: #ffffff;--ink: #212121;--muted: #757575;--faint: #bdbdbd;--grid: #eeeeee;--total-stress: #212121;--pore-pressure: #29a3e3;--effective-stress: #d95f02;--friction: #646ef6;--dilate: #ef6c00;--contract: #0b6ea8;--structure: #9e9e9e;--accent: #ff9800;--state-active: #ef6c00;--state-rest: #2e7d32;--state-passive: #6a1b9a;--plane: #2e7d32;--zone-dilate: #e7a36a;--zone-contract: #9fb9d6;--load: #b71c1c;--safe-bg: #e8f5e9;--safe-fg: #1b5e20;--warn-bg: #fff3e0;--warn-fg: #e65100;--fail-bg: #ffebee;--fail-fg: #b71c1c}body{font-family:var(--font-body);font-size:var(--font-size-base);font-weight:var(--font-weight-normal);line-height:var(--line-height);color:var(--text-primary);background:var(--page-bg);min-height:100vh;padding:.5rem}.container{max-width:1200px;margin:0 auto;width:100%}.main-layout{display:grid;grid-template-columns:400px 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1.5rem;border-radius:var(--button-radius);font-weight:var(--font-weight-medium);font-size:.95rem;cursor:pointer;transition:var(--transition);box-shadow:var(--shadow-sm);text-transform:none;font-family:inherit}button:hover{background:var(--button-hover-bg);transform:translateY(-1px);box-shadow:var(--shadow-md)}button:active{transform:translateY(0);box-shadow:var(--shadow-sm)}@media(max-width:1024px){.main-layout{grid-template-columns:1fr;gap:1rem}}@media(max-width:768px){body{padding:.5rem}header{margin-bottom:2rem;padding:1rem 0}header p{font-size:1rem;padding:0 1rem}}.arrow-container{position:relative;display:flex;align-items:center;justify-content:space-between;margin:20px 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.close{position:absolute;top:.75rem;right:.75rem;width:2rem;height:2rem;padding:0;border-radius:50%;background:var(--button-secondary-bg);color:var(--text-primary);box-shadow:none;font-size:1.2rem}label>.tip,.item>span>.tip,h2>.tip,h3>.tip,th>.tip{float:right;margin-left:.5rem;margin-top:.15rem}.compact label>.tip{float:none;margin-left:.3rem;margin-top:0}.tip{display:inline-flex;align-items:center;justify-content:center;width:1.05rem;height:1.05rem;margin-left:.3rem;padding:0;border-radius:50%;background:var(--surface-muted);color:var(--text-secondary);border:1px solid var(--border-color);box-shadow:none;font-size:.68rem;font-weight:700;font-style:normal;line-height:1;vertical-align:middle;cursor:help}.tip:hover,.tip:focus-visible,.tip[aria-expanded=true]{background:var(--primary-color);border-color:var(--primary-color);color:var(--button-fg);transform:none;box-shadow:none}#tooltip{position:fixed;z-index:1000;max-width:18rem;padding:.5rem .7rem;border-radius:6px;background:var(--tooltip-bg);color:var(--tooltip-fg);font-size:.8rem;font-weight:400;line-height:1.4;box-shadow:var(--shadow-md);pointer-events:none;opacity:0;transition:opacity .12s ease-in-out}#tooltip.shown{opacity:1}button.reset{width:100%;margin-top:.9rem;padding:.45rem .75rem;font-size:.8rem;background:var(--button-secondary-bg);color:var(--button-secondary-fg);border:1px solid var(--border-color);box-shadow:none}button.reset:hover{background:var(--border-color);color:var(--text-primary);transform:none}@media(prefers-reduced-motion:reduce){button,#tooltip{transition:none}button:hover{transform:none}}