/*
Theme Name: Song Academic
Theme URI: https://song.hinext.cc/
Author: HiNext
Description: A source-aware Chinese academic website theme for AI and medical image research.
Version: 1.0.0
Requires at least: 6.0
Requires PHP: 7.4
Text Domain: song-academic
*/

:root {
  --song-ink: #06172b;
  --song-ink-2: #0a2340;
  --song-blue: #0f4c81;
  --song-teal: #19b9bd;
  --song-teal-soft: #c9f6f4;
  --song-sky: #e8f5fb;
  --song-paper: #f6f8fb;
  --song-white: #ffffff;
  --song-gold: #e5b769;
  --song-text: #18344d;
  --song-muted: #62758a;
  --song-border: rgba(14, 63, 101, .13);
  --song-shadow: 0 18px 55px rgba(6, 36, 67, .12);
  --song-radius: 22px;
  --song-max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--song-paper);
  color: var(--song-text);
  font-family: "Noto Sans SC", "Microsoft YaHei", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
img { display: block; max-width: 100%; height: auto; }
button, input, textarea { font: inherit; }
.song-screen-reader { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); border: 0; }
.song-container { width: min(calc(100% - 40px), var(--song-max)); margin-inline: auto; }

.song-site-header { position: absolute; z-index: 30; top: 0; left: 0; width: 100%; color: #fff; transition: background .25s ease, box-shadow .25s ease; }
.song-site-header.is-scrolled { position: fixed; background: rgba(5, 22, 42, .93); box-shadow: 0 7px 24px rgba(0,0,0,.18); backdrop-filter: blur(14px); }
.song-header-inner { min-height: 78px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.song-brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; letter-spacing: .02em; }
.song-brand-mark { display: grid; place-items: center; width: 37px; height: 37px; border: 1px solid rgba(201,246,244,.68); border-radius: 50%; font-size: 12px; font-weight: 700; letter-spacing: .08em; color: var(--song-teal-soft); }
.song-brand-copy { display: grid; line-height: 1.2; }
.song-brand-copy strong { font-size: 15px; font-weight: 700; }
.song-brand-copy small { margin-top: 3px; font-size: 10px; letter-spacing: .18em; opacity: .75; }
.song-navigation { display: flex; align-items: center; gap: 24px; }
.song-navigation a { color: #fff; font-size: 14px; text-decoration: none; opacity: .88; transition: color .2s, opacity .2s; }
.song-navigation a:hover, .song-navigation a:focus { color: var(--song-teal-soft); opacity: 1; }
.song-header-cta { padding: 8px 14px; border: 1px solid rgba(201,246,244,.68); border-radius: 999px; font-weight: 600; }
.song-menu-toggle { display: none; border: 0; color: #fff; background: transparent; font-size: 26px; line-height: 1; cursor: pointer; }

.song-hero { position: relative; min-height: min(800px, 94vh); padding: 152px 0 78px; color: #fff; overflow: hidden; background: var(--song-ink); display: grid; align-items: center; }
.song-hero::before { position: absolute; inset: 0; content: ""; background: linear-gradient(90deg, rgba(3,16,34,.88) 0%, rgba(3,16,34,.72) 38%, rgba(3,16,34,.15) 78%); z-index: 1; }
.song-hero::after { position: absolute; inset: auto 6% 8% auto; content: ""; width: 310px; height: 310px; border: 1px solid rgba(44, 210, 208, .25); border-radius: 50%; box-shadow: 0 0 110px rgba(24,179,192,.18); z-index: 1; }
.song-hero-media { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center; }
.song-hero-media--portrait { object-position: 48% 34%; filter: saturate(.86) contrast(.94) brightness(.84); }
.song-hero .song-container { position: relative; z-index: 2; }
.song-eyebrow { display: inline-flex; align-items: center; gap: 9px; padding: 6px 11px; border: 1px solid rgba(200, 248, 246, .44); border-radius: 999px; color: var(--song-teal-soft); background: rgba(3,29,55,.38); font-size: 12px; letter-spacing: .08em; }
.song-eyebrow::before { content: ""; display: block; width: 6px; height: 6px; border-radius: 50%; background: var(--song-teal); box-shadow: 0 0 11px var(--song-teal); }
.song-hero-copy { max-width: 670px; }
.song-hero h1 { margin: 18px 0 18px; font-family: "Noto Serif SC", "STSong", serif; font-size: clamp(41px, 6.3vw, 78px); line-height: 1.17; letter-spacing: -.04em; font-weight: 700; }
.song-hero h1 em { display: block; color: var(--song-teal-soft); font-style: normal; font-size: .64em; letter-spacing: .03em; margin-top: 12px; }
.song-hero-lead { max-width: 590px; margin: 0; color: rgba(255,255,255,.86); font-size: clamp(16px, 2vw, 19px); }
.song-hero-actions { display: flex; flex-wrap: wrap; gap: 13px; margin-top: 32px; }
.song-button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 10px 19px; border: 1px solid transparent; border-radius: 999px; font-weight: 700; text-decoration: none; transition: transform .2s, box-shadow .2s, background .2s; }
.song-button:hover { transform: translateY(-2px); box-shadow: 0 10px 26px rgba(0,0,0,.2); }
.song-button--primary { color: #073047; background: var(--song-teal-soft); }
.song-button--ghost { border-color: rgba(255,255,255,.6); color: #fff; background: rgba(5,27,51,.18); }
.song-hero-note { margin: 22px 0 0; color: rgba(255,255,255,.56); font-size: 12px; }

.song-section { padding: 104px 0; }
.song-section--white { background: var(--song-white); }
.song-section--ink { color: #fff; background: linear-gradient(135deg, #071c34 0%, #0c3153 63%, #0a4f69 100%); }
.song-section--soft { background: linear-gradient(180deg, #f6f8fb, #ebf7f8); }
.song-section-heading { display: flex; align-items: end; justify-content: space-between; gap: 28px; margin-bottom: 38px; }
.song-kicker { margin: 0 0 7px; color: #0f8c95; font-size: 12px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.song-section-heading h2 { margin: 0; color: var(--song-ink); font-family: "Noto Serif SC", "STSong", serif; font-size: clamp(30px, 4vw, 47px); letter-spacing: -.03em; line-height: 1.25; }
.song-section-heading p { max-width: 420px; margin: 0; color: var(--song-muted); font-size: 15px; }
.song-section--ink .song-section-heading h2 { color: #fff; }
.song-section--ink .song-section-heading p { color: rgba(255,255,255,.7); }
.song-section--ink .song-kicker { color: #97ebe7; }

.song-intro-grid { display: grid; grid-template-columns: 1.02fr .98fr; gap: 64px; align-items: start; }
.song-intro-copy > p { margin: 0; font-size: 18px; color: #2a455c; }
.song-intro-copy > p + p { margin-top: 18px; color: var(--song-muted); font-size: 16px; }
.song-facts { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.song-fact { padding: 24px; min-height: 151px; border: 1px solid var(--song-border); border-radius: 16px; background: #fbfdff; }
.song-fact strong { display: block; color: #0f4c81; font-family: "Noto Serif SC", serif; font-size: 28px; line-height: 1.2; }
.song-fact span { display: block; margin-top: 9px; color: var(--song-muted); font-size: 13px; line-height: 1.6; }
.song-source-line { display: flex; align-items: center; gap: 8px; margin-top: 28px; color: var(--song-muted); font-size: 12px; }
.song-source-line::before { display: block; content: ""; width: 28px; height: 1px; background: var(--song-teal); }

.song-research-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.song-research-card { position: relative; padding: 30px 27px 28px; border: 1px solid var(--song-border); border-radius: var(--song-radius); background: #fff; overflow: hidden; box-shadow: 0 10px 35px rgba(13, 58, 90, .05); transition: transform .22s, box-shadow .22s; }
.song-research-card:hover { transform: translateY(-6px); box-shadow: var(--song-shadow); }
.song-research-number { color: var(--song-teal); font-size: 13px; font-weight: 800; letter-spacing: .1em; }
.song-research-card h3 { margin: 17px 0 11px; color: var(--song-ink); font-family: "Noto Serif SC", serif; font-size: 25px; line-height: 1.35; }
.song-research-card p { margin: 0; color: var(--song-muted); font-size: 14px; }
.song-research-card::after { position: absolute; width: 116px; height: 116px; right: -37px; bottom: -48px; content: ""; border: 1px solid rgba(25,185,189,.24); border-radius: 50%; }

.song-feature-split { display: grid; grid-template-columns: .95fr 1.05fr; min-height: 480px; border-radius: var(--song-radius); overflow: hidden; background: #06192e; }
.song-feature-split figure { position: relative; margin: 0; min-height: 100%; }
.song-feature-split img { width: 100%; height: 100%; object-fit: cover; }
.song-feature-split .song-activity-photo { object-position: 64% center; }
.song-feature-split figcaption { position: absolute; right: 0; bottom: 0; left: 0; z-index: 1; margin: 0; padding: 44px 24px 19px; color: rgba(255,255,255,.88); background: linear-gradient(transparent, rgba(2,13,26,.86)); font-size: 12px; line-height: 1.55; }
.song-feature-content { align-self: center; padding: 64px clamp(30px, 6vw, 80px); }
.song-feature-content .song-kicker { color: #8eeae6; }
.song-feature-content h2 { margin: 0; font-family: "Noto Serif SC", serif; font-size: clamp(32px, 4vw, 48px); line-height: 1.3; }
.song-feature-content p { color: rgba(255,255,255,.72); }
.song-feature-list { display: grid; gap: 14px; margin: 26px 0 0; padding: 0; list-style: none; }
.song-feature-list li { display: flex; gap: 11px; color: rgba(255,255,255,.87); font-size: 14px; }
.song-feature-list li::before { content: ""; flex: 0 0 auto; width: 8px; height: 8px; margin-top: .63em; border-radius: 50%; background: var(--song-teal); box-shadow: 0 0 12px rgba(25,185,189,.7); }

.song-paper-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 17px; }
.song-paper { display: grid; grid-template-columns: auto 1fr; gap: 16px; padding: 23px; border: 1px solid var(--song-border); border-radius: 17px; background: #fff; }
.song-paper-year { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 13px; color: #0b6674; background: var(--song-teal-soft); font-size: 12px; font-weight: 800; }
.song-paper h3 { margin: 0; color: var(--song-ink); font-size: 17px; line-height: 1.48; }
.song-paper p { margin: 7px 0 0; color: var(--song-muted); font-size: 13px; line-height: 1.6; }
.song-paper a { display: inline-block; margin-top: 9px; color: #087e88; font-size: 12px; font-weight: 700; }

.song-updates { display: grid; grid-template-columns: repeat(3, 1fr); gap: 19px; }
.song-update { display: flex; flex-direction: column; padding: 25px; min-height: 260px; border-radius: 18px; color: #fff; background: rgba(255,255,255,.075); border: 1px solid rgba(196,247,245,.18); }
.song-update time { color: #a3eeea; font-size: 12px; font-weight: 700; letter-spacing: .08em; }
.song-update h3 { margin: 13px 0 11px; font-size: 20px; line-height: 1.45; }
.song-update p { margin: 0; color: rgba(255,255,255,.73); font-size: 14px; }
.song-update a { margin-top: auto; padding-top: 20px; color: #baf5f3; font-size: 13px; font-weight: 800; text-decoration: none; }
.song-empty-update { grid-column: 1 / -1; padding: 32px; border: 1px dashed rgba(255,255,255,.3); border-radius: 16px; color: rgba(255,255,255,.72); }

.song-assistant { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(30px, 6vw, 82px); align-items: center; }
.song-assistant-visual { position: relative; }
.song-assistant-visual::before { position: absolute; z-index: 0; inset: -26px 15% auto auto; width: 220px; height: 220px; content: ""; border-radius: 50%; background: rgba(25,185,189,.2); filter: blur(14px); }
.song-assistant-visual img { position: relative; z-index: 1; border-radius: var(--song-radius); box-shadow: var(--song-shadow); }
.song-assistant-copy h2 { margin: 0; color: var(--song-ink); font-family: "Noto Serif SC", serif; font-size: clamp(34px, 4.5vw, 52px); line-height: 1.25; }
.song-assistant-copy p { color: var(--song-muted); }
.song-rule-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 11px; margin: 25px 0 30px; }
.song-rule { padding: 13px 14px; border-radius: 12px; color: #294961; background: #eef8f9; font-size: 13px; line-height: 1.5; }
.song-rule b { display: block; margin-bottom: 3px; color: #0c7280; }

.song-statement { display: grid; grid-template-columns: 1.1fr .9fr; gap: 40px; padding: 42px; border: 1px solid var(--song-border); border-radius: var(--song-radius); background: #fff; }
.song-statement h2 { margin: 0; font-family: "Noto Serif SC", serif; font-size: 32px; line-height: 1.35; }
.song-statement p { margin: 0; color: var(--song-muted); }
.song-statement a { color: #087e88; font-weight: 700; }

.song-page-hero { padding: 150px 0 58px; color: #fff; background: linear-gradient(135deg, #06172b, #0b4568); }
.song-page-hero h1 { margin: 9px 0 0; font-family: "Noto Serif SC", serif; font-size: clamp(36px,5vw,64px); line-height: 1.2; }
.song-content { width: min(calc(100% - 40px), 860px); margin: 0 auto; padding: 72px 0 105px; }
.song-content h2, .song-content h3 { color: var(--song-ink); font-family: "Noto Serif SC", serif; line-height: 1.35; }
.song-content h2 { margin-top: 2.2em; font-size: 30px; }
.song-content h3 { margin-top: 1.8em; font-size: 22px; }
.song-content p, .song-content li { color: #38546a; }
.song-content a { color: #087e88; }
.song-source-card { display: grid; grid-template-columns: auto 1fr; gap: 15px; margin-top: 34px; padding: 20px; border-left: 3px solid var(--song-teal); border-radius: 0 12px 12px 0; background: #edf9f9; }
.song-source-card strong { color: #105a67; }
.song-source-card span { color: var(--song-muted); font-size: 13px; }

.song-site-footer { color: rgba(255,255,255,.7); background: #06172b; }
.song-footer-main { display: grid; grid-template-columns: 1.25fr .75fr .75fr; gap: 40px; padding: 67px 0 42px; }
.song-footer-brand p { max-width: 400px; color: rgba(255,255,255,.6); font-size: 14px; }
.song-footer-heading { margin: 0 0 13px; color: #fff; font-size: 14px; }
.song-footer-list { margin: 0; padding: 0; list-style: none; }
.song-footer-list li + li { margin-top: 7px; }
.song-footer-list a { color: rgba(255,255,255,.63); font-size: 13px; }
.song-footer-bottom { display: flex; justify-content: space-between; gap: 20px; padding: 18px 0; border-top: 1px solid rgba(255,255,255,.12); color: rgba(255,255,255,.42); font-size: 12px; }

.song-reveal { opacity: 0; transform: translateY(18px); transition: opacity .58s ease, transform .58s ease; }
.song-reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 900px) {
  .song-navigation { position: fixed; top: 78px; right: 14px; left: 14px; display: none; align-items: stretch; flex-direction: column; gap: 0; padding: 13px; border: 1px solid rgba(255,255,255,.18); border-radius: 18px; background: #09233e; box-shadow: 0 18px 42px rgba(0,0,0,.3); }
  .song-navigation.is-open { display: flex; }
  .song-navigation a { padding: 10px; }
  .song-menu-toggle { display: block; }
  .song-intro-grid, .song-feature-split, .song-assistant, .song-statement { grid-template-columns: 1fr; }
  .song-research-grid { grid-template-columns: 1fr; }
  .song-paper-list, .song-updates { grid-template-columns: 1fr; }
  .song-feature-split figure { min-height: 290px; }
  .song-footer-main { grid-template-columns: 1fr 1fr; }
  .song-footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 620px) {
  .song-container { width: min(calc(100% - 28px), var(--song-max)); }
  .song-header-inner { min-height: 66px; }
  .song-navigation { top: 66px; }
  .song-brand-copy small { display: none; }
  .song-hero { min-height: 680px; padding-top: 126px; }
  .song-hero::before { background: linear-gradient(90deg, rgba(3,16,34,.9), rgba(3,16,34,.65)); }
  .song-hero-media--portrait { object-position: 50% 32%; }
  .song-hero h1 { font-size: 43px; }
  .song-section { padding: 72px 0; }
  .song-section-heading { display: block; margin-bottom: 27px; }
  .song-section-heading p { margin-top: 13px; }
  .song-facts, .song-rule-grid { grid-template-columns: 1fr; }
  .song-feature-content { padding: 40px 26px; }
  .song-statement { padding: 27px; }
  .song-footer-main { grid-template-columns: 1fr; gap: 26px; }
  .song-footer-brand { grid-column: auto; }
  .song-footer-bottom { display: block; }
  .song-footer-bottom span + span { display: block; margin-top: 4px; }
}