:root{--bg: #f4f6fa;--surface: #ffffff;--line: #e3e8ef;--ink: #16202e;--muted: #5b677a;--c-lo: #16202e;--c-le: #e08600;--c-int: #d6336c;--c-fr: #2563eb;--c-li: #7c3aed;--c-cos: #0f9d8a;--fs-body: clamp(16px, 1.25vw + 8px, 20px);--fs-small: clamp(13px, .9vw + 6px, 16px);--fs-h1: clamp(28px, 2.6vw + 12px, 44px);--fs-eq: clamp(32px, 3vw + 14px, 54px);--s-1: 4px;--s-2: 8px;--s-3: 12px;--s-4: 16px;--s-5: 24px;--radius: 18px;--tap: 48px;--shadow: 0 1px 2px rgba(22, 32, 46, .06), 0 8px 24px rgba(22, 32, 46, .06);--safe-t: env(safe-area-inset-top, 0px);--safe-r: env(safe-area-inset-right, 0px);--safe-b: env(safe-area-inset-bottom, 0px);--safe-l: env(safe-area-inset-left, 0px)}*{box-sizing:border-box}html,body{margin:0;height:100%;overflow:hidden;background:var(--bg);color:var(--ink);font:400 var(--fs-body) / 1.4 system-ui,-apple-system,"Segoe 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