:root{--bg-primary: #0d1117;--bg-secondary: #161b22;--bg-tertiary: #21262d;--bg-card: #161b22;--bg-hover: #1c2128;--text-primary: #e6edf3;--text-secondary: #8b949e;--text-muted: #6e7681;--accent-primary: #58a6ff;--accent-secondary: #79c0ff;--accent-dim: #388bfd;--success: #3fb950;--warning: #d29922;--error: #f85149;--info: #58a6ff;--border-color: #30363d;--border-light: #3d444d;--font-mono: "IBM Plex Mono", "SF Mono", Monaco, Consolas, monospace;--font-sans: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--header-height: 60px;--container-max: 1200px;--radius-sm: 4px;--radius-md: 6px;--radius-lg: 8px;--radius-xl: 12px;--transition-fast: .15s ease;--transition-normal: .2s ease}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:15px;scroll-behavior:smooth}body{font-family:var(--font-sans);background:var(--bg-primary);color:var(--text-primary);line-height:1.6;min-height:100vh;overflow-x:hidden}#app{min-height:100vh;display:flex;flex-direction:column}a{color:var(--accent-primary);text-decoration:none;transition:color var(--transition-fast)}a:hover{color:var(--accent-secondary);text-decoration:underline}.header{position:fixed;top:0;left:0;right:0;height:var(--header-height);background:var(--bg-secondary);border-bottom:1px solid var(--border-color);z-index:1000}.header-content{max-width:var(--container-max);margin:0 auto;padding:0 24px;height:100%;display:flex;align-items:center;justify-content:space-between}.logo-section{display:flex;align-items:center;gap:12px}.logo{display:flex;align-items:center;gap:8px;font-family:var(--font-mono);font-weight:600;font-size:1.1rem;color:var(--text-primary)}.logo-icon{font-size:1.3rem}.contest-badge{background:var(--bg-tertiary);border:1px solid var(--border-color);padding:3px 8px;border-radius:var(--radius-sm);font-size:.7rem;font-weight:500;color:var(--text-secondary);text-transform:uppercase;letter-spacing:.3px}.nav{display:flex;gap:4px}.nav-link{padding:8px 14px;color:var(--text-secondary);font-weight:500;font-size:.9rem;border-radius:var(--radius-md);transition:all var(--transition-fast);text-decoration:none}.nav-link:hover{color:var(--text-primary);background:var(--bg-hover);text-decoration:none}.nav-link.active{color:var(--text-primary);background:var(--bg-tertiary)}.auth-section{display:flex;align-items:center;gap:12px}.auth-buttons{display:flex;gap:8px}.user-info{display:flex;align-items:center;gap:10px}.user-avatar{width:28px;height:28px;display:flex;align-items:center;justify-content:center;background:var(--bg-tertiary);border-radius:50%;font-size:.9rem}.user-name{font-weight:500;color:var(--text-primary);font-size:.9rem}.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:8px 16px;font-family:var(--font-sans);font-size:.85rem;font-weight:500;border:1px solid transparent;border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast)}.btn-primary{background:var(--accent-dim);color:#fff;border-color:var(--accent-dim)}.btn-primary:hover{background:var(--accent-primary);border-color:var(--accent-primary)}.btn-ghost{background:transparent;color:var(--text-secondary);border-color:transparent}.btn-ghost:hover{color:var(--text-primary);background:var(--bg-hover)}.btn-outline{background:transparent;color:var(--text-primary);border-color:var(--border-light)}.btn-outline:hover{border-color:var(--accent-primary);color:var(--accent-primary)}.btn-large{padding:12px 24px;font-size:.95rem}.btn-full{width:100%}.main-content{flex:1;margin-top:var(--header-height)}.page{display:none;animation:fadeIn .2s ease}.page.active{display:block}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.hero{position:relative;min-height:calc(100vh - var(--header-height));display:flex;align-items:center;justify-content:center;padding:60px 24px;overflow:hidden}.hero-bg{position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none}.grid-pattern{position:absolute;top:0;right:0;bottom:0;left:0;background-image:linear-gradient(rgba(88,166,255,.02) 1px,transparent 1px),linear-gradient(90deg,rgba(88,166,255,.02) 1px,transparent 1px);background-size:48px 48px;-webkit-mask-image:radial-gradient(ellipse at center,black 30%,transparent 70%);mask-image:radial-gradient(ellipse at center,black 30%,transparent 70%)}.hero-content{position:relative;text-align:center;max-width:800px}.contest-status{display:inline-block;padding:6px 14px;border-radius:var(--radius-md);font-size:.8rem;font-weight:600;margin-bottom:20px}.contest-status.ended{background:#f851491a;color:var(--error);border:1px solid rgba(248,81,73,.2)}.hero-title{font-size:clamp(2.5rem,6vw,4rem);font-weight:700;line-height:1.15;margin-bottom:12px;letter-spacing:-.02em}.gradient-text{color:var(--accent-primary)}.hero-subtitle{font-size:1.1rem;color:var(--text-secondary);margin-bottom:28px}.contest-time{display:flex;justify-content:center;gap:40px;margin-bottom:40px;flex-wrap:wrap}.time-item{display:flex;flex-direction:column;gap:4px}.time-label{font-size:.7rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.time-value{font-family:var(--font-mono);font-size:.95rem;color:var(--text-primary)}.hero-stats{display:flex;justify-content:center;gap:16px;margin-bottom:40px;flex-wrap:wrap}.stat-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);padding:20px 32px;display:flex;flex-direction:column;align-items:center;gap:2px;transition:border-color var(--transition-normal)}.stat-card:hover{border-color:var(--border-light)}.stat-number{font-family:var(--font-mono);font-size:2rem;font-weight:700;color:var(--text-primary)}.stat-label{font-size:.8rem;color:var(--text-secondary)}.hero-actions{display:flex;justify-content:center;gap:12px;flex-wrap:wrap}.sponsors-section{padding:60px 24px;background:var(--bg-secondary);border-top:1px solid var(--border-color)}.section-title{text-align:center;font-size:1.1rem;font-weight:500;margin-bottom:32px;color:var(--text-secondary)}.sponsors-grid{display:flex;justify-content:center;gap:24px;flex-wrap:wrap;max-width:var(--container-max);margin:0 auto}.sponsor-card{display:block;background:var(--bg-tertiary);border:1px solid var(--border-color);border-radius:var(--radius-lg);padding:24px 40px;text-align:center;transition:border-color var(--transition-normal);text-decoration:none;color:inherit}.sponsor-card:hover{border-color:var(--border-light);text-decoration:none}.sponsor-logo{font-size:2.5rem;margin-bottom:8px}.sponsor-name{font-weight:500;color:var(--text-primary);font-size:.95rem}.about-section{padding:60px 24px}.about-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:16px;max-width:var(--container-max);margin:0 auto}.about-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius-lg);padding:24px;text-align:center;transition:border-color var(--transition-normal)}.about-card:hover{border-color:var(--border-light)}.about-icon{font-size:2rem;margin-bottom:12px}.about-card h3{font-size:1rem;margin-bottom:8px;font-weight:600}.about-card p{color:var(--text-secondary);font-size:.85rem;line-height:1.5}.page-header{padding:40px 24px 20px;max-width:var(--container-max);margin:0 auto}.page-title{font-size:1.5rem;margin-bottom:12px;font-weight:600}.contest-ended-notice{display:inline-flex;align-items:center;gap:8px;padding:10px 16px;background:#f8514914;border:1px solid rgba(248,81,73,.15);border-radius:var(--radius-md);color:var(--error);font-size:.8rem}.contest-ended-notice.small{padding:8px 12px;font-size:.75rem}.problems-table-container{padding:0 24px 48px;max-width:var(--container-max);margin:0 auto}.problems-table{width:100%;border-collapse:collapse;background:var(--bg-card);border-radius:var(--radius-lg);overflow:hidden;border:1px solid var(--border-color)}.problems-table th,.problems-table td{padding:14px 16px;text-align:left}.problems-table th{background:var(--bg-tertiary);font-weight:600;font-size:.75rem;text-transform:uppercase;letter-spacing:.3px;color:var(--text-secondary)}.problems-table tbody tr{border-top:1px solid var(--border-color);transition:background var(--transition-fast);cursor:pointer}.problems-table tbody tr:hover{background:var(--bg-hover)}.col-status{width:60px;text-align:center}.col-id{width:70px}.col-difficulty{width:90px}.col-solved{width:120px}.col-score{width:70px;text-align:right}.status-icon{font-size:1rem}.status-solved{color:var(--success)}.status-attempted{color:var(--error)}.status-none{color:var(--text-muted)}.problem-title-cell{font-weight:500;color:var(--text-primary)}.difficulty-tag{display:inline-block;padding:3px 10px;border-radius:var(--radius-sm);font-size:.7rem;font-weight:600}.difficulty-easy{background:#3fb9501f;color:var(--success)}.difficulty-medium{background:#d299221f;color:var(--warning)}.difficulty-hard{background:#f851491f;color:var(--error)}.solve-rate{font-family:var(--font-mono);font-size:.8rem;color:var(--text-secondary)}.score-value{font-family:var(--font-mono);font-weight:600;color:var(--accent-primary)}.standings-table-container{padding:0 24px 48px;max-width:var(--container-max);margin:0 auto;overflow-x:auto}.standings-table{width:100%;min-width:850px;border-collapse:collapse;background:var(--bg-card);border-radius:var(--radius-lg);overflow:hidden;border:1px solid var(--border-color)}.standings-table th,.standings-table td{padding:12px 14px;text-align:center}.standings-table th{background:var(--bg-tertiary);font-weight:600;font-size:.75rem;text-transform:uppercase;letter-spacing:.3px;color:var(--text-secondary)}.standings-table tbody tr{border-top:1px solid var(--border-color);transition:background var(--transition-fast)}.standings-table tbody tr:hover{background:var(--bg-hover)}.col-rank{width:60px}.col-user{text-align:left;min-width:160px}.col-score{width:70px}.col-penalty{width:90px}.rank-badge{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;border-radius:50%;font-weight:600;font-size:.8rem}.rank-1{background:#d4af37;color:#000}.rank-2{background:#a8a8a8;color:#000}.rank-3{background:#b87333;color:#fff}.rank-default{background:var(--bg-tertiary);color:var(--text-secondary)}.user-cell{display:flex;align-items:center;gap:8px}.user-cell-avatar{width:24px;height:24px;display:flex;align-items:center;justify-content:center;background:var(--bg-tertiary);border-radius:50%;font-size:.75rem}.total-score{font-family:var(--font-mono);font-weight:600;font-size:1rem;color:var(--accent-primary)}.penalty-time{font-family:var(--font-mono);font-size:.8rem;color:var(--text-secondary)}.problem-cell{font-family:var(--font-mono);font-size:.75rem}.problem-cell.solved{color:var(--success)}.problem-cell.attempted{color:var(--error)}.problem-cell.pending{color:var(--text-muted)}.modal{display:none;position:fixed;top:0;right:0;bottom:0;left:0;background:#0009;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:2000;align-items:center;justify-content:center;padding:24px;overflow-y:auto}.modal.active{display:flex}.modal-content{background:var(--bg-secondary);border:1px solid var(--border-color);border-radius:var(--radius-xl);max-width:480px;width:100%;max-height:90vh;overflow-y:auto;animation:modalIn .2s ease}.modal-content.problem-detail{max-width:720px}@keyframes modalIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.modal-header{display:flex;align-items:center;justify-content:space-between;padding:20px 24px;border-bottom:1px solid var(--border-color)}.modal-header h2{font-size:1.1rem;font-weight:600}.modal-close{background:none;border:none;font-size:1.3rem;color:var(--text-secondary);cursor:pointer;padding:4px;line-height:1;transition:color var(--transition-fast)}.modal-close:hover{color:var(--text-primary)}.modal-body{padding:24px}.auth-form{display:flex;flex-direction:column;gap:16px}.form-group{display:flex;flex-direction:column;gap:6px}.form-group label{font-size:.8rem;font-weight:500;color:var(--text-secondary)}.form-group input{background:var(--bg-tertiary);border:1px solid var(--border-color);border-radius:var(--radius-md);padding:10px 14px;font-family:var(--font-sans);font-size:.9rem;color:var(--text-primary);transition:border-color var(--transition-fast)}.form-group input:focus{outline:none;border-color:var(--accent-primary)}.form-group input::placeholder{color:var(--text-muted)}.auth-switch{text-align:center;margin-top:16px;font-size:.85rem;color:var(--text-secondary)}.problem-meta{display:flex;gap:10px;margin-bottom:20px}.problem-difficulty,.problem-score{padding:4px 12px;border-radius:var(--radius-sm);font-size:.75rem;font-weight:600}.problem-score{background:#58a6ff1a;color:var(--accent-primary)}.problem-description{color:var(--text-secondary);margin-bottom:20px;line-height:1.7;font-size:.9rem}.problem-section{margin-bottom:20px}.problem-section h3{font-size:.9rem;margin-bottom:10px;color:var(--text-primary);font-weight:600}.problem-section div{color:var(--text-secondary);font-size:.85rem;line-height:1.6}.sample-container{display:flex;flex-direction:column;gap:12px}.sample-box{display:grid;grid-template-columns:1fr 1fr;gap:12px}.sample-input,.sample-output{background:var(--bg-tertiary);border:1px solid var(--border-color);border-radius:var(--radius-md);padding:12px}.sample-label{font-size:.7rem;text-transform:uppercase;letter-spacing:.3px;color:var(--text-muted);margin-bottom:6px}.sample-content{font-family:var(--font-mono);font-size:.8rem;white-space:pre-wrap;color:var(--text-primary)}.submit-section{padding-top:16px;border-top:1px solid var(--border-color)}.footer{background:var(--bg-secondary);border-top:1px solid var(--border-color);padding:32px 24px}.footer-content{max-width:var(--container-max);margin:0 auto;display:flex;flex-direction:column;align-items:center;gap:16px}.footer-brand{display:flex;align-items:center;gap:8px;font-weight:500;font-size:.9rem}.footer-links{display:flex;gap:24px;flex-wrap:wrap;justify-content:center}.footer-links a{color:var(--text-secondary);font-size:.85rem}.footer-links a:hover{color:var(--accent-primary)}.footer-copyright{font-size:.75rem;color:var(--text-muted)}@media(max-width:768px){.header-content{padding:0 16px}.logo-text{display:none}.nav{position:fixed;bottom:0;left:0;right:0;background:var(--bg-secondary);border-top:1px solid var(--border-color);justify-content:space-around;padding:8px 0}.nav-link{padding:10px 14px;font-size:.8rem}.auth-buttons .btn{padding:6px 10px;font-size:.8rem}.hero{padding:40px 16px 100px}.hero-stats{gap:10px}.stat-card{padding:16px 20px}.stat-number{font-size:1.5rem}.contest-time{flex-direction:column;gap:12px}.sample-box{grid-template-columns:1fr}.footer-links{gap:16px}}.toast{position:fixed;top:80px;left:50%;transform:translate(-50%) translateY(-20px);background:var(--bg-secondary);border:1px solid var(--border-color);border-radius:var(--radius-lg);padding:16px 24px;display:flex;align-items:center;gap:12px;box-shadow:0 8px 32px #0006;z-index:3000;opacity:0;visibility:hidden;transition:all .3s ease}.toast.show{opacity:1;visibility:visible;transform:translate(-50%) translateY(0)}.toast.toast-error{border-color:var(--error);background:#f851491a}.toast.toast-success{border-color:var(--success);background:#3fb9501a}.toast-icon{font-size:1.2rem}.toast-message{font-size:.9rem;color:var(--text-primary);font-weight:500}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--bg-secondary)}::-webkit-scrollbar-thumb{background:var(--bg-tertiary);border-radius:4px}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}