/* bicac.lol — 潮汐纸面视觉系统（移动端优先） */
:root {
  --ink: #14352f;
  --ink-soft: #2a5249;
  --mist: #eaf6f1;
  --paper: #f7fcf9;
  --foam: #ffffff;
  --coral: #ff5a5f;
  --coral-deep: #e03e44;
  --gold: #f2c14e;
  --sky: #d6efff;
  --teal: #1f8a7a;
  --teal-bright: #2bbbad;
  --line: rgba(20, 53, 47, 0.12);
  --shadow: 0 18px 40px rgba(20, 53, 47, 0.12);
  --radius: 22px;
  --nav-h: 64px;
  --font-display: "ZCOOL XiaoWei", "Noto Serif SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(214, 239, 255, 0.9), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(255, 90, 95, 0.12), transparent 50%),
    linear-gradient(180deg, var(--mist) 0%, var(--paper) 40%, #eef8f4 100%);
  line-height: 1.75;
  min-height: 100vh;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--teal);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--coral-deep);
}

.tide-wrap {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

/* 顶部推广条 */
.tide-promo {
  background: linear-gradient(90deg, rgba(31, 138, 122, 0.12), rgba(255, 90, 95, 0.1));
  border-bottom: 1px solid var(--line);
  padding: 10px 0 6px;
}

.tide-promo-inner {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tide-promo-label {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
  text-align: center;
}

.tide-dl-rail {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 8px;
}

.tide-dl-item {
  width: calc(25% - 8px);
  max-width: 72px;
  text-decoration: none;
  color: var(--ink-soft);
  text-align: center;
  font-size: 11px;
}

.tide-dl-item img {
  width: 56px;
  height: 56px;
  margin: 0 auto 4px;
  border-radius: 16px;
  object-fit: cover;
  box-shadow: 0 8px 18px rgba(20, 53, 47, 0.14);
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}

.tide-dl-item:hover img {
  transform: translateY(-3px) scale(1.04);
  box-shadow: 0 12px 24px rgba(20, 53, 47, 0.2);
}

.tide-dl-item span {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

@media (min-width: 768px) {
  .tide-dl-item {
    width: calc(12.5% - 8px);
  }
}

/* 导航 */
.tide-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(247, 252, 249, 0.82);
  border-bottom: 1px solid var(--line);
  height: var(--nav-h);
}

.tide-nav-row {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.tide-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
}

.tide-brand img {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  object-fit: cover;
}

.tide-brand strong {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 400;
  letter-spacing: 0.04em;
}

.tide-nav-links {
  display: none;
  gap: 18px;
  align-items: center;
}

.tide-nav-links a {
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.tide-nav-links a:hover {
  color: var(--coral);
}

.tide-nav-toggle {
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--foam);
  display: grid;
  place-items: center;
  gap: 5px;
  cursor: pointer;
}

.tide-nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  transition: 0.2s ease;
}

.tide-nav-toggle.is-active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.tide-nav-toggle.is-active span:nth-child(2) {
  opacity: 0;
}
.tide-nav-toggle.is-active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.tide-nav-links.is-open {
  display: flex;
  position: absolute;
  top: var(--nav-h);
  left: 0;
  right: 0;
  flex-direction: column;
  background: rgba(247, 252, 249, 0.96);
  padding: 16px;
  border-bottom: 1px solid var(--line);
  box-shadow: var(--shadow);
}

@media (min-width: 900px) {
  .tide-nav-toggle {
    display: none;
  }
  .tide-nav-links {
    display: flex;
  }
}

/* 固定下载条 */
.tide-sticky-bar {
  position: fixed;
  top: var(--nav-h);
  left: 0;
  right: 0;
  z-index: 45;
  transform: translateY(-120%);
  opacity: 0;
  pointer-events: none;
  transition: transform 0.28s ease, opacity 0.28s ease;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
  padding: 8px 0;
}

.tide-sticky-bar.is-visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

body.has-sticky-dl {
  padding-top: 0;
}

body.has-sticky-dl .tide-hero,
body.has-sticky-dl .tide-crumb,
body.has-sticky-dl .tide-page-head {
  scroll-margin-top: 140px;
}

/* Hero — 全幅视觉平面 */
.tide-hero {
  position: relative;
  min-height: min(92vh, 860px);
  display: grid;
  align-items: end;
  overflow: hidden;
  isolation: isolate;
}

.tide-hero-bg {
  position: absolute;
  inset: 0;
  z-index: -2;
  background:
    linear-gradient(180deg, rgba(20, 53, 47, 0.15) 0%, rgba(20, 53, 47, 0.72) 100%),
    url("shot-comic-serial.jpg") center/cover no-repeat;
  transform: scale(1.02);
  animation: tide-drift 18s ease-in-out infinite alternate;
}

.tide-hero-glow {
  position: absolute;
  inset: auto -20% -30% -20%;
  height: 55%;
  z-index: -1;
  background: radial-gradient(circle at 50% 0%, rgba(43, 187, 173, 0.35), transparent 60%);
  animation: tide-pulse 6s ease-in-out infinite;
}

.tide-hero-copy {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 48px 0 56px;
  color: #fff;
}

.tide-hero-copy .tide-brand-mark {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 9vw, 4.6rem);
  line-height: 1.1;
  margin: 0 0 12px;
  text-shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
}

.tide-hero-copy h1 {
  font-size: clamp(1.15rem, 3.6vw, 1.65rem);
  font-weight: 600;
  margin: 0 0 12px;
  max-width: 18em;
}

.tide-hero-copy p {
  margin: 0;
  max-width: 28em;
  color: rgba(255, 255, 255, 0.9);
  font-size: 1rem;
}

@keyframes tide-drift {
  from {
    transform: scale(1.02) translateY(0);
  }
  to {
    transform: scale(1.06) translateY(-1.5%);
  }
}

@keyframes tide-pulse {
  0%,
  100% {
    opacity: 0.7;
  }
  50% {
    opacity: 1;
  }
}

@keyframes tide-rise {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.tide-reveal {
  animation: tide-rise 0.7s ease both;
}

/* 章节通用 */
.tide-section {
  padding: 48px 0;
}

.tide-section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  font-weight: 400;
  margin: 0 0 12px;
  color: var(--ink);
}

.tide-section h3 {
  font-size: 1.15rem;
  margin: 28px 0 10px;
  color: var(--ink);
}

.tide-lead {
  color: var(--ink-soft);
  margin: 0 0 24px;
  max-width: 42em;
}

.tide-prose p {
  margin: 0 0 1em;
  color: var(--ink-soft);
  text-align: justify;
}

.tide-prose p:last-child {
  margin-bottom: 0;
}

/* 图文交错 */
.tide-split {
  display: grid;
  gap: 24px;
  align-items: center;
  margin: 28px 0;
}

.tide-split figure {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  background: var(--foam);
}

.tide-split img {
  width: 100%;
  aspect-ratio: 9/16;
  object-fit: cover;
  object-position: top;
  max-height: 520px;
}

.tide-split figcaption {
  padding: 10px 14px;
  font-size: 0.85rem;
  color: var(--ink-soft);
  background: var(--foam);
}

@media (min-width: 860px) {
  .tide-split {
    grid-template-columns: 1fr 1.15fr;
    gap: 40px;
  }
  .tide-split.is-flip {
    grid-template-columns: 1.15fr 1fr;
  }
  .tide-split.is-flip figure {
    order: 2;
  }
  .tide-split img {
    aspect-ratio: 3/4;
  }
}

/* 卡片网格（仅用于交互/内容块） */
.tide-mosaic {
  display: grid;
  gap: 16px;
  margin-top: 24px;
}

@media (min-width: 700px) {
  .tide-mosaic {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 980px) {
  .tide-mosaic.is-tri {
    grid-template-columns: repeat(3, 1fr);
  }
}

.tide-tile {
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 10px 28px rgba(20, 53, 47, 0.06);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.tide-tile:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.tide-tile h3 {
  margin-top: 0;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 400;
}

.tide-tile p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.tide-tile-media {
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 14px;
}

.tide-tile-media img {
  width: 100%;
  aspect-ratio: 4/5;
  object-fit: cover;
  object-position: top;
}

/* 横幅图文带 */
.tide-ribbon {
  margin: 32px 0;
  padding: 28px;
  border-radius: 28px;
  background:
    linear-gradient(135deg, rgba(31, 138, 122, 0.12), rgba(214, 239, 255, 0.65)),
    var(--foam);
  border: 1px solid var(--line);
  display: grid;
  gap: 20px;
}

@media (min-width: 800px) {
  .tide-ribbon {
    grid-template-columns: 1.2fr 0.8fr;
    align-items: center;
  }
}

.tide-ribbon img {
  border-radius: 18px;
  max-height: 360px;
  width: 100%;
  object-fit: cover;
  object-position: top;
}

/* CTA 区（非 Hero） */
.tide-cta {
  margin: 40px 0;
  padding: 36px 28px;
  border-radius: 28px;
  text-align: center;
  background: linear-gradient(145deg, #14352f, #1f6f5b);
  color: #fff;
  box-shadow: var(--shadow);
}

.tide-cta h2 {
  color: #fff;
  margin-bottom: 10px;
}

.tide-cta p {
  margin: 0 auto 20px;
  max-width: 34em;
  color: rgba(255, 255, 255, 0.88);
}

.tide-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 0 26px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--coral), #ff7d5c);
  color: #fff !important;
  text-decoration: none !important;
  font-weight: 600;
  box-shadow: 0 10px 24px rgba(255, 90, 95, 0.35);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.tide-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 28px rgba(255, 90, 95, 0.45);
}

.tide-btn.is-ghost {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.45);
  box-shadow: none;
  margin-left: 10px;
}

/* 面包屑 */
.tide-crumb {
  padding: 18px 0 0;
  font-size: 0.88rem;
  color: var(--ink-soft);
}

.tide-crumb a {
  color: var(--teal);
  text-decoration: none;
}

.tide-crumb span {
  margin: 0 6px;
  opacity: 0.5;
}

/* 子页头 */
.tide-page-head {
  padding: 28px 0 8px;
}

.tide-page-head h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 5vw, 2.4rem);
  font-weight: 400;
  margin: 0 0 10px;
}

.tide-page-head p {
  margin: 0;
  color: var(--ink-soft);
  max-width: 40em;
}

.tide-legal {
  padding-bottom: 56px;
}

.tide-legal h2 {
  font-family: var(--font-display);
  font-size: 1.45rem;
  font-weight: 400;
  margin: 32px 0 12px;
}

.tide-legal p,
.tide-legal li {
  color: var(--ink-soft);
}

.tide-legal ul {
  padding-left: 1.2em;
}

/* 错误页 */
.tide-error {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 48px 16px;
}

.tide-error-code {
  font-family: var(--font-display);
  font-size: clamp(4rem, 18vw, 7rem);
  line-height: 1;
  background: linear-gradient(120deg, var(--teal), var(--coral));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin: 0;
}

.tide-error h1 {
  margin: 8px 0 12px;
  font-size: 1.4rem;
}

.tide-error p {
  color: var(--ink-soft);
  max-width: 28em;
  margin: 0 auto 24px;
}

/* 页脚 */
.tide-foot {
  margin-top: 24px;
  padding: 36px 0 48px;
  border-top: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.45);
}

.tide-foot-grid {
  display: grid;
  gap: 24px;
}

@media (min-width: 700px) {
  .tide-foot-grid {
    grid-template-columns: 1.4fr 1fr 1fr;
  }
}

.tide-foot h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 400;
  margin: 0 0 12px;
}

.tide-foot p,
.tide-foot a {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.tide-foot a {
  display: block;
  text-decoration: none;
  margin-bottom: 8px;
}

.tide-foot a:hover {
  color: var(--coral);
}

.tide-copy {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--ink-soft);
  text-align: center;
}

/* FAQ / 列表强调 */
.tide-faq details {
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 14px 18px;
  margin-bottom: 10px;
}

.tide-faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--ink);
}

.tide-faq p {
  margin: 10px 0 0;
  color: var(--ink-soft);
}

.tide-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0 8px;
}

.tide-chip {
  font-size: 0.82rem;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(31, 138, 122, 0.1);
  color: var(--teal);
  border: 1px solid rgba(31, 138, 122, 0.18);
}

.tide-quote {
  margin: 28px 0;
  padding: 22px 24px;
  border-left: 4px solid var(--coral);
  background: rgba(255, 255, 255, 0.65);
  border-radius: 0 18px 18px 0;
  color: var(--ink-soft);
  font-size: 1.02rem;
}