/* ============================================================
   dt-binance.com — BinanceHelper Tools + Q&A
   ============================================================ */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --blue:#2563eb;--blue-dark:#1d4ed8;--blue-light:rgba(37,99,235,.08);
  --dark:#111827;--text:#374151;--text2:#6b7280;
  --bg:#fff;--bg2:#f9fafb;--border:#e5e7eb;
  --green:#10b981;--red:#ef4444;
  --footer-bg:#111827;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --container:1200px;
}
html{scroll-behavior:smooth;scroll-padding-top:72px}
body{font-family:var(--sans);background:var(--bg);color:var(--text);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--blue);text-decoration:none;transition:color .15s}
a:hover{color:var(--blue-dark)}
img{max-width:100%}
.container{max-width:var(--container);margin:0 auto;padding:0 20px}

/* ===== Buttons ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:14px 32px;border-radius:8px;font-size:1rem;font-weight:600;cursor:pointer;transition:all .2s;border:none}
.btn--blue{background:var(--blue);color:#fff}
.btn--blue:hover{background:var(--blue-dark);color:#fff;transform:translateY(-1px);box-shadow:0 4px 16px rgba(37,99,235,.3)}
.btn--outline{border:2px solid var(--blue);color:var(--blue);background:transparent}
.btn--outline:hover{background:var(--blue-light);color:var(--blue-dark)}
.btn--sm{padding:10px 20px;font-size:.9rem}

/* ===== Header ===== */
.hdr{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.96);backdrop-filter:blur(8px);border-bottom:1px solid var(--border);transition:box-shadow .2s}
.hdr--scrolled{box-shadow:0 2px 12px rgba(0,0,0,.06)}
.hdr__inner{display:flex;align-items:center;height:64px;gap:20px}
.hdr__brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:1.1rem;color:var(--dark)}
.hdr__brand svg{width:28px;height:28px}
.hdr__nav{display:flex;gap:24px;margin-left:auto}
.hdr__nav a{font-size:.9rem;color:var(--text2);font-weight:500;position:relative;transition:color .15s}
.hdr__nav a:hover{color:var(--dark)}
.hdr__nav a::after{content:'';position:absolute;bottom:-4px;left:0;width:0;height:2px;background:var(--blue);transition:width .2s}
.hdr__nav a:hover::after{width:100%}
.lang-switch{display:flex;gap:4px}
.lang-switch a{font-size:.78rem;padding:4px 8px;border-radius:4px;color:var(--text2);font-weight:600;border:1px solid transparent;transition:all .15s}
.lang-switch a:hover{color:var(--blue);border-color:var(--blue)}
.lang-switch a.active{background:var(--blue-light);color:var(--blue);border-color:rgba(37,99,235,.3)}
.hdr__cta{padding:8px 20px;background:var(--blue);color:#fff;border-radius:6px;font-size:.88rem;font-weight:600;white-space:nowrap;transition:all .2s}
.hdr__cta:hover{background:var(--blue-dark);color:#fff;box-shadow:0 2px 8px rgba(37,99,235,.3)}
.hdr__burger{display:none;background:none;border:none;color:var(--dark);cursor:pointer}
.hdr__burger svg{width:24px;height:24px}

/* Mobile overlay */
.mob{position:fixed;inset:0;background:rgba(255,255,255,.98);backdrop-filter:blur(12px);z-index:200;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:24px;opacity:0;pointer-events:none;transition:opacity .2s}
.mob--open{opacity:1;pointer-events:all}
.mob__close{position:absolute;top:16px;right:16px;background:none;border:none;cursor:pointer;color:var(--dark)}
.mob__close svg{width:28px;height:28px}
.mob a{font-size:1.2rem;color:var(--dark);font-weight:500}
.mob a:hover{color:var(--blue)}
.mob__lang{display:flex;gap:8px;margin-top:8px}
.mob__lang a{font-size:.85rem;padding:6px 12px;border-radius:4px;color:var(--text2)}
.mob__lang a.on{color:var(--blue);background:var(--blue-light)}

@media(max-width:768px){
  .hdr__nav,.lang-switch,.hdr__cta{display:none}
  .hdr__burger{display:block}
}

/* ===== Hero ===== */
.hero{padding:80px 0 60px;background:linear-gradient(135deg,#eff6ff 0%,#dbeafe 50%,#eff6ff 100%)}
.hero__inner{text-align:center;max-width:720px;margin:0 auto}
.hero__title{font-size:2.8rem;font-weight:800;line-height:1.2;color:var(--dark);margin-bottom:16px}
.hero__title span{color:var(--blue)}
.hero__desc{font-size:1.1rem;color:var(--text2);margin-bottom:36px;line-height:1.7}
.hero__search{max-width:560px;margin:0 auto;position:relative}
.hero__search input{width:100%;padding:16px 56px 16px 20px;border:2px solid var(--border);border-radius:12px;font-size:1rem;background:#fff;outline:none;transition:border-color .2s;font-family:var(--sans)}
.hero__search input:focus{border-color:var(--blue);box-shadow:0 0 0 3px var(--blue-light)}
.hero__search button{position:absolute;right:8px;top:50%;transform:translateY(-50%);width:40px;height:40px;border:none;background:var(--blue);color:#fff;border-radius:8px;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:background .2s}
.hero__search button:hover{background:var(--blue-dark)}
@media(max-width:640px){
  .hero{padding:48px 0 36px}
  .hero__title{font-size:1.8rem}
  .hero__desc{font-size:.95rem}
}

/* ===== Section title ===== */
.section-title{text-align:center;font-size:1.8rem;font-weight:700;color:var(--dark);margin-bottom:12px}
.section-desc{text-align:center;color:var(--text2);margin-bottom:40px;font-size:1rem}
.section-more{display:block;text-align:center;margin-top:24px;font-size:.95rem;font-weight:600;color:var(--blue)}
.section-more:hover{color:var(--blue-dark)}

/* ===== Tool cards grid ===== */
.tools-sec{padding:60px 0}
.tools-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.tool-card{display:block;background:var(--bg);border:1px solid var(--border);border-radius:12px;padding:28px 24px;transition:all .2s;color:var(--text)}
.tool-card:hover{border-color:var(--blue);box-shadow:0 4px 16px rgba(37,99,235,.08);color:var(--dark);transform:translateY(-2px)}
.tool-card__icon{width:48px;height:48px;border-radius:10px;background:var(--blue-light);color:var(--blue);display:flex;align-items:center;justify-content:center;margin-bottom:14px;font-size:1.3rem}
.tool-card__icon svg{width:24px;height:24px}
.tool-card__title{font-size:1rem;font-weight:600;margin-bottom:6px;color:var(--dark)}
.tool-card__desc{font-size:.85rem;color:var(--text2);line-height:1.5}
@media(max-width:768px){.tools-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:480px){.tools-grid{grid-template-columns:1fr}}

/* ===== QA card grid ===== */
.qa-sec{padding:60px 0;background:var(--bg2)}
.qa-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}
.qa-card{display:flex;align-items:center;gap:12px;background:var(--bg);border:1px solid var(--border);border-radius:10px;padding:16px 20px;transition:all .2s;color:var(--text);text-decoration:none}
.qa-card:hover{border-color:var(--blue);box-shadow:0 4px 16px rgba(37,99,235,.08);transform:translateY(-1px)}
.qa-card__badge{width:28px;height:28px;border-radius:6px;background:var(--blue-light);color:var(--blue);display:flex;align-items:center;justify-content:center;font-size:.8rem;font-weight:700;flex-shrink:0}
.qa-card__title{font-size:.92rem;font-weight:500;color:var(--dark);line-height:1.4;flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.qa-card:hover .qa-card__title{color:var(--blue)}
.qa-card__desc{display:none}
.qa-card__arrow{color:var(--border);flex-shrink:0;transition:all .15s}
.qa-card:hover .qa-card__arrow{color:var(--blue);transform:translateX(3px)}
@media(max-width:768px){.qa-grid{grid-template-columns:1fr}}

/* Related QA cards on qa detail page */
.related-qa-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
.related-qa-card{display:flex;align-items:flex-start;gap:14px;background:var(--bg2);border:1px solid var(--border);border-radius:10px;padding:18px 20px;transition:all .2s;text-decoration:none;color:var(--text)}
.related-qa-card:hover{border-color:var(--blue);background:var(--bg);box-shadow:0 4px 16px rgba(37,99,235,.08);transform:translateY(-1px)}
.related-qa-card__badge{width:30px;height:30px;border-radius:8px;background:var(--blue-light);color:var(--blue);display:flex;align-items:center;justify-content:center;font-size:.8rem;font-weight:700;flex-shrink:0;margin-top:2px}
.related-qa-card__body{flex:1;min-width:0}
.related-qa-card__title{display:block;font-size:.92rem;font-weight:600;color:var(--dark);line-height:1.4;margin-bottom:4px}
.related-qa-card:hover .related-qa-card__title{color:var(--blue)}
.related-qa-card__desc{display:block;font-size:.8rem;color:var(--text2);line-height:1.5;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.related-qa-card__arrow{color:var(--border);flex-shrink:0;margin-top:6px;transition:all .15s}
.related-qa-card:hover .related-qa-card__arrow{color:var(--blue);transform:translateX(3px)}
@media(max-width:640px){.related-qa-grid{grid-template-columns:1fr}}

/* ===== Tool page (calculator) ===== */
.tool-page{padding:48px 0;min-height:60vh}
.tool-page__body{max-width:800px;margin:0 auto}
.tool-page__body h2{font-size:1.3rem;font-weight:600;margin:32px 0 12px;color:var(--dark)}
.tool-page__body h3{font-size:1.1rem;font-weight:600;margin:24px 0 8px;color:var(--dark)}
.tool-page__body p{margin-bottom:16px;line-height:1.8}
.tool-page__body ul,.tool-page__body ol{margin-bottom:16px;padding-left:24px}
.tool-page__body li{margin-bottom:8px;line-height:1.7}
.tool-page__body table{width:100%;border-collapse:collapse;margin:20px 0;font-size:.9rem}
.tool-page__body th,.tool-page__body td{padding:10px 14px;border:1px solid var(--border);text-align:left}
.tool-page__body th{background:var(--bg2);font-weight:600;color:var(--dark)}
.tool-page__desc{font-size:1rem;color:var(--text2);margin-bottom:32px;line-height:1.7}

/* Calculator container */
.tool-calculator{background:var(--bg);border:1px solid var(--border);border-radius:12px;padding:32px;margin-bottom:32px}
.tool-form{}
.form-group{margin-bottom:20px}
.form-group label{display:block;font-size:.9rem;font-weight:600;color:var(--dark);margin-bottom:8px}
.form-group input[type="number"],
.form-group input[type="text"],
.form-group select{width:100%;padding:12px 16px;border:1px solid var(--border);border-radius:8px;font-size:1rem;font-family:var(--sans);color:var(--dark);background:var(--bg);outline:none;transition:border-color .2s}
.form-group input:focus,.form-group select:focus{border-color:var(--blue);box-shadow:0 0 0 3px var(--blue-light)}
.form-group input[type="checkbox"]{width:auto;margin-right:8px;accent-color:var(--blue);transform:scale(1.15);vertical-align:middle}
.form-group input[type="radio"]{width:auto;margin-right:6px;accent-color:var(--blue);transform:scale(1.15);vertical-align:middle}
.form-group .radio-group{display:flex;gap:20px;margin-top:4px}
.form-group .radio-group label{display:inline-flex;align-items:center;font-weight:500;cursor:pointer;margin-bottom:0}
.form-actions{display:flex;gap:12px;margin-top:8px;flex-wrap:wrap}
.btn-calc{display:inline-flex;align-items:center;justify-content:center;padding:12px 32px;background:var(--blue);color:#fff;border:none;border-radius:8px;font-size:1rem;font-weight:600;cursor:pointer;transition:all .2s;font-family:var(--sans)}
.btn-calc:hover{background:var(--blue-dark);box-shadow:0 4px 12px rgba(37,99,235,.25)}
.btn-reset{display:inline-flex;align-items:center;justify-content:center;padding:12px 24px;background:transparent;color:var(--text2);border:1px solid var(--border);border-radius:8px;font-size:1rem;font-weight:500;cursor:pointer;transition:all .2s;font-family:var(--sans)}
.btn-reset:hover{border-color:var(--text2);color:var(--dark);background:var(--bg2)}

/* Result display */
.tool-result{margin-top:24px;padding:24px;background:var(--blue-light);border-left:4px solid var(--blue);border-radius:0 12px 12px 0;animation:fadeIn .3s ease}
.tool-result h3{font-size:1rem;font-weight:700;color:var(--blue);margin-bottom:12px}
.tool-result p{margin-bottom:8px;line-height:1.7;color:var(--text)}
.tool-result strong{color:var(--dark)}

/* Result table inside tool */
.result-table{width:100%;border-collapse:collapse;margin:8px 0;font-size:.95rem}
.result-table td{padding:10px 14px;border-bottom:1px solid rgba(37,99,235,.12)}
.result-table td:first-child{color:var(--text2);font-weight:500;white-space:nowrap;width:40%}
.result-table td:last-child{font-weight:600;color:var(--dark);text-align:right}
.result-table tr:last-child td{border-bottom:none}

/* Info tables (withdrawal-fees, fee-comparison, etc.) */
.info-table{width:100%;border-collapse:collapse;margin:20px 0;font-size:.9rem;border:1px solid var(--border);border-radius:8px;overflow:hidden}
.info-table th{background:var(--blue);color:#fff;padding:12px 14px;text-align:left;font-weight:600;font-size:.85rem}
.info-table td{padding:10px 14px;border-bottom:1px solid var(--border)}
.info-table tr:last-child td{border-bottom:none}
.info-table tr:nth-child(even){background:var(--bg2)}
.info-table tr:hover{background:var(--blue-light)}

@keyframes fadeIn{from{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:480px){
  .tool-calculator{padding:20px}
  .form-actions{flex-direction:column}
  .btn-calc,.btn-reset{width:100%}
}

/* ===== QA page (article) ===== */
.qa-page{padding:48px 0;min-height:60vh}
.qa-page__body{max-width:800px;margin:0 auto;line-height:1.8;color:var(--text)}
.qa-page__body h2{font-size:1.3rem;font-weight:600;margin:32px 0 12px;color:var(--dark)}
.qa-page__body h3{font-size:1.1rem;font-weight:600;margin:24px 0 8px;color:var(--dark)}
.qa-page__body p{margin-bottom:16px}
.qa-page__body ul,.qa-page__body ol{margin-bottom:16px;padding-left:24px}
.qa-page__body li{margin-bottom:8px}
.qa-page__body a{color:var(--blue);text-decoration:underline}
.qa-page__body a:hover{color:var(--blue-dark)}
.qa-page__body blockquote{background:var(--blue-light);border-left:3px solid var(--blue);padding:16px 20px;border-radius:0 8px 8px 0;margin:20px 0;color:var(--text)}
.qa-page__body table{width:100%;border-collapse:collapse;margin:20px 0;font-size:.9rem}
.qa-page__body th,.qa-page__body td{padding:10px 14px;border:1px solid var(--border);text-align:left}
.qa-page__body th{background:var(--bg2);font-weight:600;color:var(--dark)}
.qa-page__body code{background:var(--bg2);padding:2px 6px;border-radius:4px;font-size:.88rem}

/* ===== Breadcrumb ===== */
.breadcrumb{padding:16px 0;font-size:.85rem;color:var(--text2)}
.breadcrumb a{color:var(--text2);transition:color .15s}
.breadcrumb a:hover{color:var(--blue)}
.breadcrumb span{margin:0 6px;color:var(--border)}

/* ===== Related section ===== */
.related{padding:40px 0;border-top:1px solid var(--border);margin-top:40px}
.related__title{font-size:1.2rem;font-weight:700;color:var(--dark);margin-bottom:20px}

/* ===== CTA banner ===== */
.cta{padding:60px 0}
.cta__inner{background:linear-gradient(135deg,var(--blue) 0%,var(--blue-dark) 100%);border-radius:16px;padding:48px 40px;text-align:center;color:#fff}
.cta__title{font-size:1.6rem;font-weight:700;margin-bottom:12px}
.cta__desc{font-size:1rem;opacity:.9;margin-bottom:28px;max-width:560px;margin-left:auto;margin-right:auto;line-height:1.6}
.cta__btns{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}
.cta__btns .btn--white{background:#fff;color:var(--blue);font-weight:600}
.cta__btns .btn--white:hover{background:#f0f4ff;box-shadow:0 4px 16px rgba(0,0,0,.15)}
.cta__btns .btn--outline-white{border:2px solid rgba(255,255,255,.5);color:#fff;background:transparent}
.cta__btns .btn--outline-white:hover{border-color:#fff;background:rgba(255,255,255,.1)}
@media(max-width:640px){
  .cta__inner{padding:32px 20px}
  .cta__title{font-size:1.3rem}
  .cta__btns .btn{width:100%}
}

/* ===== Footer ===== */
.ftr{background:var(--footer-bg);color:#fff;padding:24px 0}
.ftr__inner{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px}
.ftr__left{display:flex;align-items:center;gap:8px;font-size:.85rem;color:rgba(255,255,255,.6)}
.ftr__left strong{color:#fff;font-weight:600}
.ftr__right{display:flex;gap:20px}
.ftr__right a{font-size:.85rem;color:rgba(255,255,255,.6);transition:color .15s}
.ftr__right a:hover{color:#fff}
.ftr__risk{width:100%;font-size:.75rem;color:rgba(255,255,255,.4);line-height:1.5;margin-top:12px;padding-top:12px;border-top:1px solid rgba(255,255,255,.08)}
@media(max-width:768px){
  .ftr__inner{flex-direction:column;text-align:center}
  .ftr__right{flex-wrap:wrap;justify-content:center}
}

/* ===== Page (subpages) ===== */
.page{padding:48px 0;min-height:60vh}
.page__title{font-size:1.8rem;font-weight:700;color:var(--dark);margin-bottom:24px;text-align:center}
.page__body{max-width:800px;margin:0 auto;line-height:1.8;color:var(--text)}
.page__body h2{font-size:1.3rem;font-weight:600;margin:32px 0 12px;color:var(--dark)}
.page__body p{margin-bottom:16px}
.page__body ul,.page__body ol{margin-bottom:16px;padding-left:24px}
.page__body li{margin-bottom:8px}
.page__body a{color:var(--blue);text-decoration:underline}
.page__body a:hover{color:var(--blue-dark)}
.page__body .highlight{background:var(--blue-light);border-left:3px solid var(--blue);padding:16px 20px;border-radius:0 8px 8px 0;margin:20px 0}

/* ===== Search / filter box ===== */
.filter-box{max-width:480px;margin:0 auto 32px;position:relative}
.filter-box input{width:100%;padding:12px 44px 12px 16px;border:1px solid var(--border);border-radius:8px;font-size:.95rem;outline:none;font-family:var(--sans);transition:border-color .2s}
.filter-box input:focus{border-color:var(--blue);box-shadow:0 0 0 3px var(--blue-light)}
.filter-box svg{position:absolute;right:14px;top:50%;transform:translateY(-50%);width:18px;height:18px;color:var(--text2)}

/* ===== Category chips / pills ===== */
.chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-bottom:28px}
.chip{display:inline-flex;align-items:center;padding:6px 16px;border-radius:20px;font-size:.85rem;font-weight:500;color:var(--text2);background:var(--bg2);border:1px solid var(--border);cursor:pointer;transition:all .15s}
.chip:hover,.chip.active{background:var(--blue-light);color:var(--blue);border-color:rgba(37,99,235,.3)}

/* ===== 404 ===== */
.err{text-align:center;padding:120px 20px;min-height:60vh}
.err__code{font-size:6rem;font-weight:800;color:var(--blue)}
.err__title{font-size:1.4rem;margin:16px 0 8px;color:var(--dark)}
.err__desc{color:var(--text2);margin-bottom:24px}
.err__btns{display:flex;gap:12px;justify-content:center}

/* ===== Back to top ===== */
.back-top{position:fixed;bottom:24px;right:24px;width:40px;height:40px;border-radius:50%;background:var(--blue);color:#fff;border:none;cursor:pointer;display:none;align-items:center;justify-content:center;box-shadow:0 2px 8px rgba(0,0,0,.15);z-index:50;transition:transform .2s}
.back-top:hover{transform:translateY(-2px)}
.back-top svg{width:18px;height:18px}

/* ===== List page ===== */
.list-page{padding:48px 0;min-height:60vh}
.list-page__title{font-size:1.8rem;font-weight:700;color:var(--dark);margin-bottom:8px;text-align:center}
.list-page__desc{text-align:center;color:var(--text2);margin-bottom:32px}