.tank-page { --tank-blue:#07539a; --tank-sky:#159bdd; --tank-green:#36b54a; color:var(--tank-blue); }
.tank-page main { overflow:hidden; background:#fff; }
.tank-content { width:min(690px,calc(100% - 48px)); margin-inline:auto; }
.tank-breadcrumb { width:min(710px,calc(100% - 48px)); height:38px; margin:auto; display:flex; align-items:center; gap:8px; color:#4c7da9; font-size:10px; font-weight:700; }
.tank-breadcrumb a { text-decoration:none; }

.tank-hero { height:270px; background:linear-gradient(105deg,#effbff 0%,#e5f8ff 44%,#c9efff 100%); }
.tank-hero-inner { position:relative; width:min(760px,100%); height:270px; margin:auto; overflow:hidden; }
.tank-hero-image { position:absolute; inset:0 0 0 40%; background:url("assets/tank-cleaning/hero-hd.webp") center/cover no-repeat; }
.tank-hero-image::before { content:""; position:absolute; inset:0; background:linear-gradient(90deg,#eaf9ff 0%,rgba(234,249,255,.66) 13%,transparent 36%); }
.tank-hero-copy { position:relative; z-index:2; width:48%; padding:44px 0 0 40px; }
.tank-hero h1 { margin:0 0 10px; color:#073f83; font-size:36px; font-weight:900; line-height:1.25; letter-spacing:.01em; }
.tank-hero h1 span { color:#159de0; font-size:1.22em; }
.tank-hero p { margin:0 0 15px; color:#174e88; font-size:15px; font-weight:750; line-height:1.6; }
.tank-hero a { width:190px; min-height:40px; display:flex; align-items:center; justify-content:center; gap:14px; border-radius:999px; color:#fff; background:linear-gradient(90deg,#16a7ea,#0067bd); box-shadow:0 8px 18px rgba(0,103,189,.23); font-size:13px; font-weight:800; }
.tank-hero a span { font-size:18px; }

.tank-benefits { position:relative; z-index:3; margin-top:-4px; }
.tank-benefits-inner { width:min(714px,calc(100% - 40px)); min-height:102px; margin:auto; display:grid; grid-template-columns:repeat(4,1fr); overflow:hidden; border-radius:16px 16px 0 0; background:rgba(255,255,255,.94); box-shadow:0 8px 23px rgba(17,104,155,.12); }
.tank-benefits article { min-width:0; display:flex; flex-direction:column; align-items:center; justify-content:center; gap:2px; border-right:1px solid #dbeef6; text-align:center; }
.tank-benefits article:last-child { border-right:0; }
.tank-benefits img { width:48px; height:48px; object-fit:cover; object-position:center; }
.tank-benefits h2 { margin:0; color:#07539a; font-size:12px; font-weight:850; line-height:1.45; }

.tank-about { padding:30px 0 22px; }
.tank-about-grid { display:grid; grid-template-columns:42% 58%; align-items:center; gap:16px; }
.tank-about h2,.tank-section-heading h2,.tank-price h2,.tank-faq h2 { margin:0 0 13px; color:#073f83; font-size:25px; font-weight:900; line-height:1.3; }
.tank-about p { margin:0 0 5px; color:#315f88; font-size:12px; font-weight:650; line-height:1.65; }
.tank-about img { width:100%; height:205px; object-fit:contain; }

.tank-problems { padding:24px 0 25px; background:linear-gradient(180deg,#e8f9ff,#f8fdff); }
.tank-problems h2,.tank-reasons > .tank-content > h2 { margin:0 0 16px; color:#073f83; font-size:24px; font-weight:900; text-align:center; }
.tank-problem-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:20px; }
.tank-problem-grid article { text-align:center; }
.tank-problem-grid img { width:108px; height:100px; margin:0 auto 6px; border-radius:50%; object-fit:cover; }
.tank-problem-grid h3 { margin:0; color:#073f83; font-size:12px; font-weight:850; line-height:1.45; }

.tank-reasons { padding:25px 0 24px; background:linear-gradient(180deg,#f6fff4,#effceb); }
.tank-reasons > .tank-content > h2 span { margin-left:5px; font-size:1.18em; }
.tank-reason-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:8px; }
.tank-reason-grid article { position:relative; min-height:150px; padding:36px 11px 12px; border-radius:7px; background:#fff; box-shadow:0 6px 14px rgba(38,124,84,.06); text-align:center; }
.tank-reason-grid article > b { position:absolute; top:8px; left:12px; color:#3db64a; font-size:18px; }
.tank-reason-grid img { width:52px; height:52px; margin:0 auto 3px; object-fit:cover; border-radius:50%; }
.tank-reason-grid h3 { margin:0 0 4px; color:#073f83; font-size:13px; font-weight:900; }
.tank-reason-grid p { margin:0; color:#345f82; font-size:9px; font-weight:650; line-height:1.45; }

.tank-flow-section { padding:24px 0 28px; }
.tank-section-heading { display:flex; align-items:baseline; gap:22px; margin-bottom:14px; }
.tank-section-heading h2 { margin:0; white-space:nowrap; }
.tank-section-heading p { margin:0; color:#507899; font-size:11px; font-weight:650; }
.tank-flow { margin:0; padding:0; display:grid; grid-template-columns:repeat(4,1fr); gap:20px; list-style:none; }
.tank-flow li { position:relative; min-width:0; }
.tank-flow li:not(:last-child)::after { content:"›"; position:absolute; top:66px; right:-15px; color:#116bb0; font-size:29px; font-weight:400; }
.tank-flow span { color:#159de0; font-size:11px; font-weight:900; }
.tank-flow h3 { margin:0 0 6px; color:#073f83; font-size:12px; font-weight:900; }
.tank-flow img { width:100%; height:82px; border-radius:5px; object-fit:cover; }
.tank-flow p { margin:6px 0 0; color:#456e91; font-size:10px; font-weight:650; line-height:1.5; }

.tank-types { padding:21px 0 27px; background:linear-gradient(180deg,#ecfaff,#f7fdff); }
.tank-types .tank-section-heading { margin-bottom:12px; }
.tank-type-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:10px; }
.tank-type-grid article { overflow:hidden; border-radius:5px; background:#fff; box-shadow:0 6px 14px rgba(22,105,151,.08); }
.tank-type-grid img { width:100%; height:92px; object-fit:cover; }
.tank-type-grid h3 { margin:0; padding:6px 4px; color:#073f83; font-size:10px; font-weight:850; text-align:center; }

.tank-price { padding:25px 0; background:#fff; }
.tank-price-grid { display:grid; grid-template-columns:1.1fr .9fr; align-items:center; gap:25px; }
.tank-price h2 { margin-bottom:10px; }
.tank-price-grid > div:first-child p { margin:0; color:#58758d; font-size:11px; font-weight:650; line-height:1.7; }
.tank-price-card { min-height:110px; display:flex; align-items:center; gap:16px; padding:16px 20px; border:1px solid #e2eef4; border-radius:12px; background:#fff; box-shadow:0 7px 20px rgba(22,105,151,.07); }
.tank-price-card > span { width:48px; height:48px; flex:0 0 48px; display:grid; place-items:center; border-radius:50%; color:#fff; background:#70c8f2; font-size:30px; font-weight:800; }
.tank-price-card small { display:block; color:#073f83; font-size:12px; font-weight:900; }
.tank-price-card strong { display:block; color:#ea3134; font-size:31px; line-height:1.1; }
.tank-price-card em { font-size:15px; font-style:normal; }
.tank-price-card p { margin:6px 0 0; color:#687c8d; font-size:8px; font-weight:650; line-height:1.5; }

.tank-faq { padding:23px 0 30px; border-top:1px solid #edf3f6; }
.tank-faq-heading { display:flex; align-items:center; justify-content:space-between; }
.tank-faq-heading a { min-width:138px; min-height:30px; display:flex; align-items:center; justify-content:center; gap:10px; border:1px solid #9bd4f2; border-radius:999px; color:#147aba; font-size:9px; font-weight:800; }
.tank-faq-list { display:grid; grid-template-columns:1fr 1fr; gap:8px 24px; }
.tank-faq-list details { border:1px solid #e4edf3; border-radius:6px; background:#fff; box-shadow:0 3px 10px rgba(19,74,112,.04); }
.tank-faq-list summary { position:relative; min-height:32px; display:flex; align-items:center; padding:7px 30px 7px 36px; color:#275d8e; font-size:10px; font-weight:800; cursor:pointer; list-style:none; }
.tank-faq-list summary::-webkit-details-marker { display:none; }
.tank-faq-list summary::before { content:"Q"; position:absolute; left:12px; color:#079de6; font-size:14px; font-weight:900; }
.tank-faq-list summary::after { content:"+"; position:absolute; right:12px; color:#07539a; font-size:16px; }
.tank-faq-list details[open] summary::after { content:"−"; }
.tank-faq-list details p { margin:0; padding:0 14px 10px 36px; color:#527797; font-size:10px; font-weight:600; line-height:1.55; }

.tank-contact { min-height:174px; background:linear-gradient(180deg,#eaf9ff,#dff6ff 66%,#e8fbf3); }
.tank-contact-inner { position:relative; width:min(690px,calc(100% - 48px)); min-height:174px; margin:auto; display:flex; align-items:center; justify-content:center; padding-right:105px; text-align:center; }
.tank-contact h2 { margin:0 0 17px; color:#174f83; font-size:13px; font-weight:850; }
.tank-contact a { width:280px; min-height:56px; margin:auto; display:flex; align-items:center; justify-content:center; gap:13px; border-radius:999px; color:#fff; background:linear-gradient(90deg,#15a4e6,#0063b5); box-shadow:0 8px 20px rgba(0,99,181,.22); font-size:15px; font-weight:850; }
.tank-contact a span { font-size:19px; }
.tank-contact img { position:absolute; right:0; bottom:0; width:140px; height:154px; object-fit:cover; object-position:center; }

@media (max-width:860px) {
  .tank-content { width:calc(100% - 32px); }
  .tank-breadcrumb { width:calc(100% - 32px); }
  .tank-hero { height:auto; }
  .tank-hero-inner { height:auto; display:grid; grid-template-columns:1fr; }
  .tank-hero-copy { width:100%; padding:38px 22px 26px; text-align:center; }
  .tank-hero h1 { font-size:clamp(34px,9vw,48px); }
  .tank-hero p br { display:none; }
  .tank-hero a { margin:auto; }
  .tank-hero-image { position:relative; inset:auto; height:300px; background-position:center; }
  .tank-hero-image::before { background:linear-gradient(180deg,#eaf9ff 0%,transparent 28%); }
  .tank-benefits { margin-top:0; padding:0 16px; background:#eaf9ff; }
  .tank-benefits-inner { width:100%; grid-template-columns:repeat(2,1fr); border-radius:16px; }
  .tank-benefits article { min-height:132px; border-bottom:1px solid #dbeef6; }
  .tank-about { padding:42px 0; }
  .tank-about-grid { grid-template-columns:1fr; }
  .tank-about img { height:auto; }
  .tank-about h2,.tank-section-heading h2,.tank-price h2,.tank-faq h2 { font-size:27px; }
  .tank-about p { font-size:14px; }
  .tank-problems,.tank-reasons,.tank-flow-section,.tank-types,.tank-price,.tank-faq { padding:40px 0; }
  .tank-problem-grid,.tank-reason-grid,.tank-flow,.tank-type-grid { grid-template-columns:repeat(2,1fr); gap:18px; }
  .tank-problem-grid h3 { font-size:14px; }
  .tank-reason-grid article { min-height:190px; padding-top:44px; }
  .tank-reason-grid p,.tank-flow p,.tank-price-grid > div:first-child p { font-size:13px; }
  .tank-reason-grid h3,.tank-flow h3 { font-size:15px; }
  .tank-flow li:not(:last-child)::after { display:none; }
  .tank-flow img { height:145px; }
  .tank-section-heading { display:block; }
  .tank-section-heading p { font-size:13px; }
  .tank-type-grid img { height:145px; }
  .tank-type-grid h3 { font-size:13px; }
  .tank-price-grid { grid-template-columns:1fr; }
  .tank-faq-list { grid-template-columns:1fr; }
  .tank-faq-list summary { min-height:46px; font-size:13px; }
  .tank-faq-list details p { font-size:12px; }
}

@media (max-width:560px) {
  .tank-hero-image { height:240px; }
  .tank-benefits-inner,.tank-problem-grid,.tank-reason-grid,.tank-flow,.tank-type-grid { grid-template-columns:1fr 1fr; }
  .tank-benefits h2 { font-size:11px; }
  .tank-problems h2,.tank-reasons > .tank-content > h2 { font-size:22px; }
  .tank-problem-grid { gap:20px 8px; }
  .tank-reason-grid { grid-template-columns:1fr; }
  .tank-flow { grid-template-columns:1fr; }
  .tank-flow img { height:190px; }
  .tank-type-grid img { height:105px; }
  .tank-price-card { padding:15px 12px; gap:10px; }
  .tank-price-card strong { font-size:27px; }
  .tank-faq-heading { display:block; margin-bottom:15px; }
  .tank-contact { min-height:260px; }
  .tank-contact-inner { min-height:260px; padding:30px 0 120px; }
  .tank-contact a { width:100%; }
  .tank-contact img { right:50%; width:126px; height:118px; transform:translateX(50%); }
}