/* SABC 演示版 v0.9.4 版式（视觉规则 v1.3 色表：藏青 #16325E、品牌红 #B02234），
   选择器与色值取自 音形篇/小程序/sabc-demo/index.html + demo.css，只换外观、不改结构与交互。 */
:root{--brand:#16325E;--accent:#B02234;--red-tint:#FBEDEE;--navy-tint:#E8EAEF;--navy-mid:#BEC6D2;--navy-wash:#F3F5F7;--paper:#F6F6F4;--surface:#FFFFFF;--ink:#1B2230;--ink-muted:#4B5366;--ink-soft:#646C7C;--line:#E3E8F0;--line-strong:#4A5F82}
html body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.6 system-ui,-apple-system,"PingFang SC","Noto Sans SC","Microsoft YaHei",sans-serif}
body>main{max-width:1000px;margin:0 auto;padding:16px 16px 40px}
body>header{position:sticky;top:0;z-index:9;max-width:none;margin:0;display:flex;flex-wrap:wrap;justify-content:center;gap:4px 12px;padding:2px 8px;background:var(--brand)}
body>header a{color:#FFFFFF;font-size:14px;font-weight:700;text-decoration:none}
a{color:var(--brand)}
/* 标题：藏青大卡 + 红下划线 + 描边 a + 红色走马条 */
main>h1{position:relative;isolation:isolate;overflow:hidden;margin:12px 0 20px;padding:28px 56px 62px 20px;border-radius:24px;background:var(--brand);color:#FFFFFF;font-size:clamp(30px,5.5vw,48px);line-height:1.25;font-weight:900;letter-spacing:-.035em;text-decoration:underline;text-decoration-color:var(--accent);text-decoration-thickness:5px;text-underline-offset:8px;text-decoration-skip-ink:none;overflow-wrap:anywhere}
main>h1::before{content:"a";position:absolute;z-index:-1;right:4px;top:-30px;font:900 170px/1 system-ui,sans-serif;color:transparent;-webkit-text-stroke:2px #4A5F82;transform:rotate(-12deg);pointer-events:none}
main>h1::after{content:"S · A · B · C · 音 · 形 · 规则 · S · A · B · C · 音 · 形 · 规则 ·";position:absolute;left:0;bottom:0;width:200%;height:34px;display:flex;align-items:center;padding-left:16px;white-space:nowrap;background:var(--accent);color:#FFFFFF;font:800 14px/34px system-ui,sans-serif;letter-spacing:.14em;pointer-events:none}
@media(prefers-reduced-motion:no-preference){main>h1::after{animation:sabc-marquee 24s linear infinite}@keyframes sabc-marquee{to{transform:translateX(-50%)}}}
/* 卡片 */
main section,main .card,main article,#panel{background:var(--surface);border:1px solid var(--line);border-radius:22px;padding:18px 16px;margin:0 0 20px;box-shadow:0 7px 0 color-mix(in srgb,#16325E 1.96%,transparent),0 12px 28px color-mix(in srgb,#16325E 3.14%,transparent);overflow-wrap:anywhere}
main section section,main section article,main article section{box-shadow:none;margin:12px 0;background:var(--navy-wash);border-radius:16px}
main section>h2,main #panel>h2{padding-bottom:10px;border-bottom:2px solid color-mix(in srgb,#16325E 9.41%,transparent);margin:0 0 12px;font-size:21px;line-height:1.45;font-weight:800;letter-spacing:-.025em;color:var(--brand)}
main section>h2::before,main #panel>h2::before{content:"";display:inline-block;width:9px;height:18px;background:var(--brand);border-radius:3px;margin-right:8px;vertical-align:-2px;box-shadow:3px 3px 0 var(--accent)}
main article>h2,main article>h3{margin:0 0 4px;font-size:clamp(30px,8vw,42px);line-height:1.2;font-weight:900;letter-spacing:-.025em;color:var(--brand)}
main article{background:linear-gradient(145deg,#FFFFFF 55%,#FBEDEE)}
.meaning{color:var(--ink);font-weight:700}
/* 规则目录：入口卡，右侧箭头 */
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:12px}
.grid>a.card{position:relative;display:block;margin:0;padding:18px 42px 18px 18px;color:var(--ink);font-weight:700;text-decoration:none}
.grid>a.card::after{content:"";position:absolute;right:20px;top:50%;width:9px;height:9px;border-top:2px solid var(--brand);border-right:2px solid var(--brand);transform:translateY(-50%) rotate(45deg)}
.locked{padding:12px 0;border-bottom:1px solid var(--line);color:var(--ink-muted)}
.muted{color:var(--ink-muted)}
/* 按钮与输入 */
button,select,input{font:inherit;color:var(--ink)}
main button{min-height:44px;padding:8px 22px;margin:4px 6px 4px 0;border-radius:999px;border:1px solid var(--brand);background:var(--brand);color:#FFFFFF;font-weight:800;box-shadow:0 4px 0 #0E2240;cursor:pointer}
main button:disabled{opacity:.5;box-shadow:none}
@media (hover:hover){main button:not(:disabled):hover{background:#1E3F73}}
main select,main input:not([type=checkbox]){width:100%;max-width:100%;min-height:48px;padding:10px 12px;margin:6px 0 14px;border:1px solid var(--line-strong);border-radius:12px;background:var(--surface)}
main label{font-weight:700;color:var(--brand)}
main>a,main nav a,main section>a,main article>a,main #panel>a{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:6px 18px;margin:4px 6px 4px 0;border-radius:999px;border:1.5px solid var(--accent);background:var(--surface);color:var(--accent);font-weight:800;text-decoration:none}
main>a[href^="/practice"]{background:var(--brand);border-color:var(--brand);color:#FFFFFF;box-shadow:0 4px 0 #0E2240}
summary{min-height:44px;padding:8px 0;color:var(--brand);font-weight:700;cursor:pointer}
#records{border:1px solid var(--line);border-radius:12px;background:var(--navy-wash)}
:where(button,a,input,textarea,select,summary):focus-visible{outline:3px solid var(--accent);outline-offset:4px;box-shadow:0 0 0 7px #FFFFFF}
dialog{border:1px solid var(--line);border-radius:22px}
@media(max-width:500px){main>h1{padding:26px 56px 60px 18px;font-size:32px;border-radius:20px}main>h1::before{font-size:150px;top:-10px;right:-8px}}
/* 首页：标题卡 + 角色入口（SABC v0.9.4 .role） */
.home .role{position:relative;display:flex;align-items:center;gap:14px;margin:0 0 14px;padding:20px 42px 20px 16px;background:var(--surface);border:1px solid var(--line);border-radius:22px;box-shadow:0 6px 18px color-mix(in srgb,#16325E 4.31%,transparent);color:var(--ink);text-decoration:none;font-weight:700}
.home .role b{display:inline-flex;flex:none;align-items:center;justify-content:center;width:54px;height:54px;border-radius:50%;background:var(--brand);color:#FFFFFF;font-size:24px;border:3px solid var(--brand);box-shadow:0 0 0 3px var(--accent)}
.home .role span{display:flex;flex-direction:column;min-width:0}.home .role strong{font-size:18px;color:var(--brand)}.home .role small{font-size:14px;color:var(--ink-muted)}
.home .role::after{content:"";position:absolute;right:20px;top:50%;width:9px;height:9px;border-top:2px solid var(--brand);border-right:2px solid var(--brand);transform:translateY(-50%) rotate(45deg)}
/* 底部标签栏（SABC .student-nav） */
.student-nav{position:sticky;bottom:0;z-index:8;display:flex;justify-content:space-around;max-width:1000px;margin:0 auto;padding:4px 8px calc(4px + env(safe-area-inset-bottom));background:var(--surface);border-top:1px solid var(--line);box-shadow:0 -4px 20px color-mix(in srgb,#16325E 3.14%,transparent)}
.student-nav a{flex:1;display:flex;align-items:center;justify-content:center;min-height:48px;color:var(--ink-muted);font-weight:700;text-decoration:none;border-radius:18px 18px 0 0}
.student-nav a[aria-current]{background:var(--accent);color:#FFFFFF}
/* 词卡：音标胶囊、规则字母高亮 */
.ipa{display:inline-block;max-width:100%;padding:2px 12px;border:1px solid #BEC6D2;border-radius:999px;background:#E8EAEF;color:var(--brand);font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:16px;overflow-wrap:anywhere}
.hl{background:#FBEDEE;color:#B02234;padding:0 3px;border-radius:5px;text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:5px}
html body{min-height:100vh;min-height:100dvh;display:flex;flex-direction:column}body>main{flex:1 0 auto;width:100%}.student-nav{width:100%}
.shell>p{font-size:18px;color:var(--ink-muted);margin:0 0 20px}
.shell>a.primary{background:var(--brand);border-color:var(--brand);color:#FFFFFF;box-shadow:0 4px 0 #0E2240;min-width:160px}
main article>.ipa{margin:4px 0 6px}