/* 七日主题：只改变视觉，不改变页面文字与结构。 */

body.theme-ocean { color-scheme: light; }

body.theme-cyber {
  --bg:#f5fbff; --paper:#ffffff; --text:#24304f; --muted:#66708d; --line:#cbdaf0;
  --accent:#7a45df; --accent2:#06a6c9; --soft:#edf2ff; --danger:#d94f75;
  --shadow:0 18px 46px rgba(68,73,159,.16);
  background-image:linear-gradient(rgba(85,75,190,.055) 1px,transparent 1px),linear-gradient(90deg,rgba(0,164,199,.055) 1px,transparent 1px);
  background-size:34px 34px;
}
.theme-cyber .sea-bg { background:linear-gradient(145deg,#f4eaff,#dff9ff 58%,#fff); }
.theme-cyber .brand-mark,.theme-cyber .primary { background:linear-gradient(135deg,#8247e5,#08a8c9); box-shadow:0 12px 30px rgba(105,67,210,.26); }
.theme-cyber .topbar { border-bottom:1px solid rgba(96,67,190,.16); }
.theme-cyber .message-card,.theme-cyber .compose-card,.theme-cyber .auth-card { border-color:#c9d4ef; box-shadow:8px 8px 0 rgba(14,165,197,.08),-5px -5px 0 rgba(124,69,222,.07); }
.theme-cyber .message-card:before { content:""; position:absolute; inset:0 auto 0 0; width:3px; background:linear-gradient(#7d46df,#08abc6); }
.theme-cyber .eyebrow { color:#7241ce; }
.theme-cyber .hero h1 span,.theme-cyber .compose-copy h1 span { color:#7251d1; text-shadow:2px 2px 0 #c8f6ff; }

body.theme-glass {
  --bg:#f2f8ff; --paper:rgba(255,255,255,.72); --text:#24415a; --muted:#668096; --line:rgba(255,255,255,.9);
  --accent:#397fba; --accent2:#65b8c8; --soft:rgba(224,244,250,.72); --shadow:0 22px 58px rgba(67,119,148,.16);
  background:linear-gradient(135deg,#e2f5ff,#f7efff 52%,#fff8ed);
}
.theme-glass .sea-bg { background:radial-gradient(circle at 18% 20%,#bceeff 0 12%,transparent 35%),radial-gradient(circle at 82% 18%,#ead6ff 0 10%,transparent 34%); }
.theme-glass .topbar,.theme-glass .message-card,.theme-glass .compose-card,.theme-glass .auth-card,.theme-glass .weather-note,.theme-glass .feedback-card { background:rgba(255,255,255,.58); backdrop-filter:blur(24px) saturate(1.2); border:1px solid rgba(255,255,255,.88); }
.theme-glass .brand-mark,.theme-glass .primary { background:linear-gradient(135deg,rgba(44,131,184,.94),rgba(87,175,191,.94)); }
.theme-glass .message-card:hover { box-shadow:0 28px 62px rgba(74,123,157,.2); }

body.theme-eva {
  --bg:#faf8ff; --paper:#fff; --text:#312b4e; --muted:#756e8a; --line:#ded5ed;
  --accent:#6b4bb3; --accent2:#65a338; --soft:#f0eaff; --danger:#d95c63; --shadow:0 18px 48px rgba(79,60,128,.14);
  background:linear-gradient(120deg,#faf7ff,#f4faee);
}
.theme-eva .sea-bg { background:linear-gradient(155deg,#eadfff,#f5edff 55%,#f3faea); }
.theme-eva .brand-mark,.theme-eva .primary { background:linear-gradient(135deg,#6745a7 0 62%,#78ad42 62%); }
.theme-eva .message-card,.theme-eva .compose-card,.theme-eva .auth-card { border-radius:8px 24px 8px 24px; border:2px solid #d8cdec; }
.theme-eva .message-card:before { content:"01"; position:absolute; right:18px; top:50px; color:rgba(108,72,174,.08); font-size:64px; font-weight:900; letter-spacing:-.08em; }
.theme-eva .eyebrow { color:#6c49ae; border-left:5px solid #79a942; padding-left:9px; }
.theme-eva .hero h1 span,.theme-eva .compose-copy h1 span { color:#6749a8; }

body.theme-win98 {
  --bg:#e9f5f5; --paper:#f4f4f4; --text:#161d2b; --muted:#556174; --line:#aab5c0;
  --accent:#2767a3; --accent2:#208a83; --soft:#e5edf1; --danger:#b83d4d; --shadow:7px 7px 0 rgba(45,70,85,.14);
  font-family:"MS Sans Serif",Tahoma,"Microsoft YaHei",sans-serif;
  background:#dcefee;
}
.theme-win98 .sea-bg { background:linear-gradient(135deg,#c7e7e6,#edf7ef); }
.theme-win98 .topbar,.theme-win98 .message-card,.theme-win98 .compose-card,.theme-win98 .auth-card,.theme-win98 .weather-note,.theme-win98 .feedback-card { border-radius:2px; border:2px solid; border-color:#fff #7f8c97 #7f8c97 #fff; background:#f2f2f2; box-shadow:var(--shadow); }
.theme-win98 .brand-mark,.theme-win98 .primary { border-radius:1px; background:linear-gradient(90deg,#174b82,#2c87a0); box-shadow:none; }
.theme-win98 .topbar { height:72px; margin-top:8px; }
.theme-win98 input,.theme-win98 textarea,.theme-win98 .upload-zone { border-radius:1px; }
.theme-win98 .message-card:hover { transform:translate(-2px,-2px); box-shadow:9px 9px 0 rgba(45,70,85,.16); }

body.theme-throne {
  --bg:#fbf8ef; --paper:#fffef9; --text:#433726; --muted:#786d5a; --line:#dfd2b6;
  --accent:#8b6630; --accent2:#a98a4d; --soft:#f5eddb; --danger:#a84e50; --shadow:0 20px 48px rgba(92,69,36,.14);
  background:#fbf8ef;
}
.theme-throne .sea-bg { background:linear-gradient(150deg,#f0e2c4,#faf6e9 60%,#fff); }
.theme-throne .brand-mark,.theme-throne .primary { background:linear-gradient(145deg,#6f5028,#aa8447); }
.theme-throne .message-card,.theme-throne .compose-card,.theme-throne .auth-card { border:1px solid #d7c59f; border-radius:18px 4px 18px 4px; box-shadow:0 18px 42px rgba(83,62,31,.13); }
.theme-throne .message-card:after { content:"◆"; position:absolute; right:18px; top:18px; color:#b2935d; opacity:.24; }
.theme-throne .eyebrow { color:#8b6934; letter-spacing:.15em; }
.theme-throne .hero h1,.theme-throne .compose-copy h1,.theme-throne .message-title { font-family:Georgia,"Noto Serif SC",serif; }
.theme-throne .hero h1 span,.theme-throne .compose-copy h1 span { color:#89652f; }

body.theme-classical {
  --bg:#fbf8f0; --paper:#fffdf7; --text:#3e3931; --muted:#766f63; --line:#ded6c7;
  --accent:#a64b43; --accent2:#3f8068; --soft:#f3eee1; --danger:#b84040; --shadow:0 18px 44px rgba(86,70,47,.12);
  font-family:"Noto Serif SC","Songti SC","SimSun",serif;
  background-color:#fbf8f0;
  background-image:radial-gradient(rgba(115,91,58,.045) .8px,transparent .8px);
  background-size:7px 7px;
}
.theme-classical .sea-bg { background:linear-gradient(160deg,#efe8d8,#f8f2e7 58%,#fffdf8); }
.theme-classical .brand-mark { border-radius:4px; background:#a64b43; box-shadow:0 8px 20px rgba(166,75,67,.22); }
.theme-classical .primary { background:linear-gradient(135deg,#a64b43,#bd695c); }
.theme-classical .message-card,.theme-classical .compose-card,.theme-classical .auth-card { border:1px solid #d9cfbc; border-radius:3px; box-shadow:0 16px 36px rgba(82,67,45,.11); }
.theme-classical .message-card:before { content:""; position:absolute; inset:9px; border:1px solid rgba(166,75,67,.09); pointer-events:none; }
.theme-classical .eyebrow { color:#9d463f; }
.theme-classical .hero h1,.theme-classical .compose-copy h1 { font-weight:600; letter-spacing:.01em; }
.theme-classical .hero h1 span,.theme-classical .compose-copy h1 span { color:#9e493f; }

body[class*="theme-"] .message-card,
body[class*="theme-"] .compose-card,
body[class*="theme-"] .auth-card,
body[class*="theme-"] .feedback-card { transition:transform .28s,box-shadow .28s,border-color .28s,background .28s; }

@media (prefers-reduced-motion:reduce) {
  body[class*="theme-"] * { animation:none!important; }
}