/* ============================================================
   KLEIN LAYOUT
   assets/css/layout.css
============================================================ */
.page { min-height: 100dvh; display: flex; flex-direction: column; }
/* 居中内容（portal、forge） */
.layout-centered {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--sp-7) var(--sp-5);
}
.centered-inner { width: 100%; max-width: var(--content-md); display: flex; flex-direction: column; gap: var(--sp-6); }
.centered-inner-sm { max-width: var(--content-sm); }
.centered-inner-lg { max-width: var(--content-lg); }
/* 对话界面（渡口） */
.layout-chat { flex: 1; display: flex; flex-direction: column; overflow: hidden; }
.chat-messages {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: var(--sp-4);
  padding: var(--sp-6) var(--sp-5);
  max-width: var(--content-md);
  width: 100%;
  margin: 0 auto;
}
.chat-input-wrap {
  padding: var(--sp-4) var(--sp-5) var(--sp-6);
  max-width: var(--content-md);
  width: 100%;
  margin: 0 auto;
}
/* 全屏专注（碎纸机） */
.layout-focus { align-items: center; justify-content: center; padding: var(--sp-7) var(--sp-5); }
.focus-inner {
  width: 100%;
  max-width: var(--content-sm);
  display: flex;
  flex-direction: column;
  gap: var(--sp-5);
  text-align: center;
}
/* Grid helpers */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: var(--sp-4); }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--sp-4); }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--sp-4); }
@media (max-width: 640px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }
/* Flex helpers */
.flex         { display: flex; }
.flex-col     { display: flex; flex-direction: column; }
.flex-center  { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.gap-sm { gap: var(--sp-2); }
.gap-md { gap: var(--sp-4); }
.gap-lg { gap: var(--sp-6); }