/* ================================================================
   v4：画框式版式（植物水彩边框 + 顶部品牌条 + 卡内分栏）
   ================================================================ */

/* 页面底色与四角植物装饰 */
html{background:#FBF7EE}
body{
  padding:20px;
  background:
    radial-gradient(900px 420px at 80% 0%, rgba(168,212,182,.10), transparent 60%),
    radial-gradient(760px 380px at 0% 100%, rgba(201,162,39,.06), transparent 60%),
    #FBF7EE;
}
/* 植物装饰放在画框内部、内容之下 */
.app-shell::before,.app-shell::after,.auth-frame::before,.auth-frame::after{
  content:"";position:absolute;pointer-events:none;z-index:0;
  background-repeat:no-repeat;background-size:contain;
}
.app-shell::before,.auth-frame::before{
  left:-70px;top:64px;width:320px;height:320px;opacity:.38;
  background-image:url("assets/deco-tl.webp");background-position:left top;
}
.app-shell::after,.auth-frame::after{
  right:-80px;bottom:-60px;width:430px;height:430px;opacity:.42;
  background-image:url("assets/deco-br.webp");background-position:right bottom;
}
.app-shell>*,.auth-frame>*{position:relative;z-index:1}

/* 应用画框 */
.app-shell,.auth-frame{position:relative;z-index:1;max-width:1400px;margin:0 auto;
  background:rgba(255,253,247,.94);border:1px solid #E7E0CE;border-radius:22px;
  box-shadow:0 24px 70px rgba(31,90,71,.10);overflow:hidden;
  display:flex;flex-direction:column;min-height:calc(100vh - 40px)}
.auth-frame{max-width:1180px}

/* 顶部品牌条 */
.brandbar{display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:13px 22px;border-bottom:1px solid var(--line);
  background:linear-gradient(180deg,rgba(255,253,247,.98),rgba(251,248,239,.9))}
.bb-left{display:flex;align-items:center;gap:16px;min-width:0}
.bb-sep{width:1px;height:28px;background:var(--line-strong);flex:none}
.bb-slogan{font-family:var(--serif);font-size:13.5px;color:var(--ink-2);letter-spacing:.06em;
  display:flex;flex-direction:column;line-height:1.45;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.bb-slogan em{font-style:normal;font-size:9.5px;letter-spacing:.26em;color:#A79E86;margin-top:1px}
.bb-right{display:flex;align-items:center;gap:10px;flex:none}
.chip-user{border:1px solid var(--line-strong);border-radius:999px;padding:5px 13px;font-size:12.5px;
  color:var(--ink-2);background:rgba(255,255,255,.7);letter-spacing:.04em}
.brandbar .brand{font-size:19px}
.brandbar .brandicon{width:40px;height:40px;border-radius:11px;font-size:18px}

/* 主体：侧栏 + 工作区 */
.app-main{display:grid;grid-template-columns:212px minmax(0,1fr);flex:1;min-height:0}
.side{position:static;width:auto;height:auto;padding:18px 12px 14px;display:flex;flex-direction:column;
  border-right:1px solid var(--line);
  background:linear-gradient(180deg,rgba(244,249,241,.75),rgba(255,253,247,.35))}
.side .nav{display:flex;flex-direction:column;gap:4px;margin:0}
.side .nav button{display:flex;align-items:center;gap:10px;width:100%;padding:10px 14px;
  border-radius:10px;font-size:14px;color:var(--ink-2);background:transparent;border:0;
  text-align:left;min-height:42px;transition:background var(--t-fast) var(--ease-out),color var(--t-fast) var(--ease-out)}
.side .nav button:hover{background:rgba(31,90,71,.06);color:var(--green-deep)}
.side .nav button.active{background:var(--green);color:#FFFDF6;box-shadow:0 6px 16px rgba(31,90,71,.18);font-weight:650}
.side .nav button.active .ico{color:#FFFDF6}
.side .nav button .ico{font-size:15px;opacity:.9}
.side .side-art{margin-top:auto;height:104px;border-radius:12px;border:1px solid var(--line);
  background:url("assets/art-mountain.jpg") center 32%/cover no-repeat;position:relative;overflow:hidden}
.side .side-quote{margin:12px 6px 10px;font-family:var(--kai);font-size:12.5px;line-height:1.85;color:var(--ink-2)}
.side .side-quote::before{font-size:20px;line-height:.5}
.side .sidefoot{border-top:1px solid var(--line);padding-top:10px;margin:0 6px}
.side .sidefoot strong{font-size:13px}
.side .sidefoot{font-size:11.5px;line-height:1.7;color:var(--muted)}

.workspace{padding:20px 28px 26px;min-width:0;display:flex;flex-direction:column}
.crumb{font-size:11px;letter-spacing:.16em;color:var(--muted);margin-bottom:10px;text-transform:uppercase}
.crumb i{margin:0 7px;font-style:normal;color:var(--line-strong)}
.workspace main{flex:1;max-width:1080px;margin:0 auto;width:100%;padding-bottom:96px}
.workspace .site-footer{margin-top:auto;padding-top:14px;border-top:1px solid var(--line);
  display:flex;justify-content:space-between;font-size:11.5px;color:var(--muted)}

/* 身份页 / 首屏 */
.roles-stage{display:grid;grid-template-columns:minmax(230px,330px) minmax(0,1fr);gap:34px;
  align-items:center;padding:30px 42px;flex:1}
.roles-ling{display:flex;justify-content:center;align-items:center}
.roles-ling picture{width:min(300px,100%);animation:lingBreathe 6.8s ease-in-out infinite}
.roles-ling img{width:100%;height:auto;display:block}
.roles-copy .eyebrow{margin-bottom:10px}
.roles-copy h1{font-size:clamp(25px,2.8vw,36px);line-height:1.4}
.roles-sub{margin:10px 0 22px;color:var(--ink-2);line-height:1.9;max-width:520px}
.role-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.role-card{position:relative;background:#FFFDF7;border:1px solid var(--line);border-radius:16px;
  padding:20px 20px 42px;text-align:left;transition:transform var(--t-base) var(--ease-out),box-shadow var(--t-base) var(--ease-out),border-color var(--t-base)}
.role-card:hover{transform:translateY(-3px);box-shadow:0 14px 32px rgba(31,90,71,.10);border-color:var(--sage-200)}
.role-icon{display:grid;place-items:center;width:42px;height:42px;border-radius:12px;
  background:var(--sage-100);color:var(--green-deep);font-family:var(--serif);font-size:19px;font-weight:700}
.teacher-role .role-icon{background:var(--gold-soft);color:#8A6A1F}
.role-card h2{margin-top:14px;font-size:18px;letter-spacing:.06em}
.role-card p{margin-top:8px;font-size:13px;color:var(--muted);line-height:1.8}
.role-card .arrow{position:absolute;right:18px;bottom:14px;color:var(--muted);font-size:16px;transition:transform var(--t-fast)}
.role-card:hover .arrow{color:var(--green);transform:translate(2px,-2px)}
.frame-footer{display:flex;justify-content:space-between;padding:13px 22px;border-top:1px solid var(--line);
  font-size:11.5px;color:var(--muted)}

/* 卡片与间距贴合示意图（更紧凑、更大圆角） */
.card{border-radius:16px;padding:22px}
.sectionhead{margin:26px 0 12px}
.home-hero{border-radius:18px;padding:26px 30px}
.hero{border-radius:18px}

@media (max-width:1180px){
  .app-main{grid-template-columns:196px minmax(0,1fr)}
  .workspace{padding:18px 20px 24px}
}
@media (max-width:980px){
  body{padding:10px}
  .app-shell,.auth-frame{min-height:calc(100vh - 20px);border-radius:18px}
  .app-main{grid-template-columns:1fr}
  .side{display:none}
  .workspace{padding:16px 16px 90px}
  .brandbar{padding:11px 14px}
  .bb-slogan{display:none}
  .roles-stage{grid-template-columns:1fr;padding:20px 18px;gap:16px}
  .roles-ling{order:-1}
  .roles-ling picture{width:min(200px,54%)}
  .role-grid{grid-template-columns:1fr}
  body::before{width:200px;height:200px;opacity:.35}
  body::after{width:220px;height:220px;opacity:.3}
}
@media (prefers-reduced-motion:reduce){
  .roles-ling picture{animation:none}
}

/* 词条页签改为示意图的胶囊按钮 */
.lesson-tabs{border-bottom:0;gap:8px;margin:16px 0 14px}
.lesson-tabs button{border-radius:999px;padding:8px 18px;background:rgba(255,253,247,.9);
  border:1px solid var(--line);color:var(--ink-2);font-size:13.5px}
.lesson-tabs button:hover{border-color:var(--sage-200);color:var(--green-deep)}
.lesson-tabs button.active{background:var(--green);border-color:var(--green);color:#FFFDF6;font-weight:650;
  box-shadow:0 6px 14px rgba(31,90,71,.16)}
.lesson-tabs button.active::after{display:none}

/* 移动端搜索框不溢出 */
.searchbar{max-width:100%}
.searchbar input{min-width:0}
@media (max-width:640px){
  .s-hero{padding:20px 16px}
  .searchbar{padding:4px 4px 4px 12px}
  .searchbar input{font-size:14px}
  .searchbar .btn{padding:0 12px;font-size:13px}
}

/* Mobile navigation must override the generic .app-shell > * rule. */
.route-back{margin-right:12px;min-height:44px;letter-spacing:normal;text-transform:none}
@media (max-width:700px){
  .app-shell > nav.mobile{
    display:flex;position:fixed;inset:auto 0 0;z-index:100;
    width:100%;margin:0;border-radius:0;
    padding:8px max(10px,env(safe-area-inset-right)) calc(8px + env(safe-area-inset-bottom)) max(10px,env(safe-area-inset-left));
    background:rgba(255,253,247,.98);border-top:1px solid var(--line);
    box-shadow:0 -4px 18px rgba(31,90,71,.06);
  }
  .app-shell > nav.mobile button{min-width:0;min-height:48px;touch-action:manipulation}
  .app-shell .workspace{padding-bottom:calc(90px + env(safe-area-inset-bottom))}
  .app-shell > .ling-fab{position:fixed;z-index:101;bottom:calc(86px + env(safe-area-inset-bottom))}
  .app-shell > .ling-panel{position:fixed;z-index:102;bottom:calc(158px + env(safe-area-inset-bottom));max-height:calc(100dvh - 180px - env(safe-area-inset-bottom))}
  #toast{bottom:calc(90px + env(safe-area-inset-bottom))}
  html{scroll-padding-bottom:calc(90px + env(safe-area-inset-bottom))}
}