/* ===== K12 深智课堂 Styles — Education Theme ===== */

:root {
  --k12-bg: #f8f6f3;
  --k12-bg-warm: #fefcf9;
  --k12-card: #ffffff;
  --k12-text: #1a1a2e;
  --k12-dim: #6b7280;
  --k12-light: #9ca3af;
  --k12-border: #e8e5e0;
  --k12-accent: #4f46e5;
  --k12-accent-light: #eef2ff;
  --k12-success: #059669;
  --k12-radius: 16px;
  --k12-shadow: 0 2px 16px rgba(0,0,0,.06);
  --k12-shadow-hover: 0 8px 32px rgba(0,0,0,.1);
}

/* --- Hide main topbar on K12 pages --- */
body.k12-active .topbar { display: none; }

/* --- K12 Topbar --- */
.k12-topbar {
  background: var(--k12-bg-warm); border-bottom: 1px solid var(--k12-border);
  padding: 12px 0; position: sticky; top: 0; z-index: 100;
}
.k12-topbar .k12-container {
  display: flex; align-items: center; justify-content: space-between;
}
.k12-topbar-brand {
  font-size: 18px; font-weight: 900; color: var(--k12-accent);
  text-decoration: none; display: flex; align-items: center; gap: 8px;
}
.k12-topbar-links { display: flex; gap: 20px; align-items: center; }
.k12-topbar-links a {
  color: var(--k12-dim); text-decoration: none; font-size: 14px; font-weight: 500;
  transition: color .2s; cursor: pointer;
}
.k12-topbar-links a:hover, .k12-topbar-links a.active { color: var(--k12-accent); }
.k12-topbar-right { display: flex; align-items: center; gap: 14px; font-size: 13px; }
.k12-topbar-right .k12-balance {
  background: var(--k12-accent-light); color: var(--k12-accent);
  padding: 4px 12px; border-radius: 8px; font-weight: 600;
}
.k12-topbar-right .k12-user { color: var(--k12-dim); }
.k12-topbar-right a {
  color: var(--k12-accent); text-decoration: none; font-weight: 600; cursor: pointer;
}
.k12-topbar-right .k12-back-main {
  color: var(--k12-light); font-size: 12px;
}

/* --- Pages Base --- */
#page-k12, #page-k12-class, #page-k12-report {
  background: var(--k12-bg);
  min-height: 100vh;
  color: var(--k12-text);
  font-family: 'Noto Sans SC', -apple-system, sans-serif;
}

/* --- Remove dark orbs, use subtle warm bg --- */
.k12-orbs { display: none; }

/* --- Container --- */
.k12-container { max-width: 1100px; margin: 0 auto; padding: 0 20px; position: relative; }

/* --- Hero --- */
.k12-hero {
  text-align: center; padding: 60px 0 20px;
  background: linear-gradient(180deg, var(--k12-bg-warm), var(--k12-bg));
}
.k12-hero h1 {
  font-size: 38px; font-weight: 900; margin-bottom: 12px;
  color: var(--k12-text);
}
.k12-hero h1 em {
  font-style: normal; color: var(--k12-accent);
}
.k12-hero p { color: var(--k12-dim); font-size: 16px; max-width: 520px; margin: 0 auto; line-height: 1.7; }

/* --- Settings bar --- */
.k12-settings {
  display: flex; justify-content: center; gap: 12px; margin: 24px 0 36px;
  flex-wrap: wrap;
}
.k12-settings select {
  background: var(--k12-card); border: 1px solid var(--k12-border);
  color: var(--k12-text); padding: 8px 16px; border-radius: 10px;
  font-size: 14px; cursor: pointer;
}
.k12-settings select:focus { outline: none; border-color: var(--k12-accent); }

/* --- Tutor Card Grid --- */
.k12-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 22px; padding-bottom: 40px;
}

.k12-card {
  background: var(--k12-card);
  border: 1px solid var(--k12-border);
  border-radius: var(--k12-radius);
  overflow: hidden; cursor: pointer;
  transition: transform .25s, box-shadow .25s;
}
.k12-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--k12-shadow-hover);
}

.k12-card-banner {
  height: 130px; position: relative;
  display: flex; align-items: center; justify-content: center;
  background: var(--card-gradient, linear-gradient(135deg, #3b82f6, #1d4ed8));
}
.k12-card-banner::after {
  content: ''; position: absolute; inset: 0; opacity: .08;
  background-size: 30px 30px;
  background-image: radial-gradient(circle, #fff 1px, transparent 1px);
}
.k12-card-avatar {
  width: 72px; height: 72px; border-radius: 50%;
  border: 4px solid #fff;
  box-shadow: 0 4px 16px rgba(0,0,0,.1);
  display: flex; align-items: center; justify-content: center;
  font-size: 32px; background: #fff;
  position: relative; z-index: 1;
}
.k12-card-subject {
  position: absolute; top: 10px; left: 12px;
  padding: 3px 10px; border-radius: 8px; font-size: 11px;
  font-weight: 700; color: #fff; background: rgba(0,0,0,.2);
  z-index: 1;
}
.k12-card-calls {
  position: absolute; bottom: 8px; right: 12px;
  font-size: 11px; color: rgba(255,255,255,.85); z-index: 1;
}

.k12-card-body { padding: 16px 18px 10px; }
.k12-card-body h3 { font-size: 18px; font-weight: 800; margin-bottom: 2px; color: var(--k12-text); }
.k12-card-body .k12-personality {
  font-size: 13px; color: var(--card-color, #3b82f6);
  font-weight: 500; margin-bottom: 8px;
}
.k12-card-body .k12-desc {
  font-size: 13px; color: var(--k12-dim); line-height: 1.6;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.k12-card-footer {
  padding: 12px 18px; border-top: 1px solid var(--k12-border);
  display: flex; justify-content: space-between; align-items: center;
}
.k12-card-price { font-size: 14px; font-weight: 700; color: var(--k12-text); }
.k12-card-price small { font-weight: 400; color: var(--k12-light); font-size: 11px; }
.k12-card-btn {
  background: var(--card-color, #3b82f6);
  border: none; color: #fff; padding: 7px 18px; border-radius: 10px;
  font-size: 12px; font-weight: 700; cursor: pointer;
  transition: opacity .2s;
}
.k12-card-btn:hover { opacity: .85; }

/* --- Classroom --- */
.k12-classroom {
  display: flex; height: calc(100vh - 52px); overflow: hidden;
}

.k12-sidebar {
  width: 280px; flex-shrink: 0;
  background: var(--k12-bg-warm);
  border-right: 1px solid var(--k12-border);
  display: flex; flex-direction: column; align-items: center;
  padding: 30px 20px;
}
.k12-sidebar-avatar {
  width: 90px; height: 90px; border-radius: 50%;
  border: 4px solid var(--card-color, #3b82f6);
  box-shadow: 0 4px 20px rgba(0,0,0,.08);
  display: flex; align-items: center; justify-content: center;
  font-size: 42px; background: #fff;
  margin-bottom: 14px;
}
.k12-sidebar h2 { font-size: 20px; font-weight: 800; margin-bottom: 4px; color: var(--k12-text); text-align: center; }
.k12-sidebar .k12-subject-label {
  font-size: 12px; color: var(--card-color, #3b82f6);
  text-transform: uppercase; letter-spacing: 2px; font-weight: 600; margin-bottom: 16px;
}
.k12-sidebar .k12-sidebar-info {
  width: 100%; font-size: 13px; color: var(--k12-dim); line-height: 1.8;
}
.k12-sidebar .k12-sidebar-info strong { color: var(--k12-text); }
.k12-sidebar-actions { margin-top: auto; width: 100%; }
.k12-sidebar-actions button {
  width: 100%; padding: 10px; border-radius: 10px;
  border: 1px solid var(--k12-border); background: var(--k12-card);
  color: var(--k12-text); font-size: 13px; cursor: pointer;
  margin-top: 8px; transition: border-color .2s;
}
.k12-sidebar-actions button:hover { border-color: var(--k12-accent); }
.k12-sidebar-actions .btn-end-session {
  border-color: #fca5a5; color: #dc2626; background: #fef2f2;
}
.k12-sidebar-actions .btn-end-session:hover {
  background: #fee2e2;
}

.k12-chat-area {
  flex: 1; display: flex; flex-direction: column;
  background: #fff;
}
.k12-chat-messages {
  flex: 1; overflow-y: auto; padding: 24px 32px;
  display: flex; flex-direction: column; gap: 14px;
}
.k12-msg {
  max-width: 75%; padding: 14px 18px;
  border-radius: 16px; font-size: 14px; line-height: 1.7;
  animation: k12MsgIn .3s ease-out;
}
@keyframes k12MsgIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.k12-msg-user {
  align-self: flex-end;
  background: var(--k12-accent);
  color: #fff;
  border-bottom-right-radius: 4px;
}
.k12-msg-assistant {
  align-self: flex-start;
  background: #f3f4f6;
  color: var(--k12-text);
  border-left: 3px solid var(--card-color, #3b82f6);
  border-bottom-left-radius: 4px;
}
.k12-msg-assistant pre {
  background: #e5e7eb; padding: 10px; border-radius: 8px;
  overflow-x: auto; margin: 8px 0;
}
.k12-msg-assistant code { font-family: 'JetBrains Mono', monospace; font-size: 13px; }

.k12-chat-input-bar {
  padding: 14px 32px 18px;
  border-top: 1px solid var(--k12-border);
  display: flex; gap: 10px;
  background: var(--k12-bg-warm);
}
.k12-chat-input-bar input {
  flex: 1; background: #fff;
  border: 1px solid var(--k12-border);
  color: var(--k12-text); padding: 12px 18px;
  border-radius: 12px; font-size: 14px;
}
.k12-chat-input-bar input:focus { outline: none; border-color: var(--k12-accent); }
.k12-chat-input-bar input::placeholder { color: var(--k12-light); }
.k12-chat-input-bar > button:not(.k12-voice-btn):not(.k12-speaker-btn) {
  background: var(--k12-accent);
  border: none; color: #fff; padding: 12px 24px;
  border-radius: 12px; font-size: 14px; font-weight: 700;
  cursor: pointer; transition: opacity .2s;
}
.k12-chat-input-bar > button:not(.k12-voice-btn):not(.k12-speaker-btn):hover { opacity: .9; }

/* Voice buttons */
.k12-voice-btn, .k12-speaker-btn {
  width: 44px; height: 44px; border-radius: 50%;
  border: 2px solid var(--k12-border); background: var(--k12-card);
  font-size: 18px; cursor: pointer; flex-shrink: 0;
  transition: all .2s; display: flex; align-items: center; justify-content: center;
}
.k12-voice-btn:hover, .k12-speaker-btn:hover { border-color: var(--k12-accent); }
.k12-voice-btn.recording {
  border-color: #dc2626; background: #fef2f2;
  animation: k12Pulse 1s ease-in-out infinite;
}
.k12-speaker-btn.active { border-color: var(--k12-accent); background: var(--k12-accent-light); }
.k12-speaker-btn.muted { opacity: .4; }
@keyframes k12Pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(220, 38, 38, .3); }
  50% { box-shadow: 0 0 0 8px rgba(220, 38, 38, 0); }
}
.k12-chat-cost {
  text-align: center; font-size: 11px; color: var(--k12-light);
  padding: 4px 32px 8px; background: var(--k12-bg-warm);
}
.k12-chat-cost span { color: var(--k12-accent); }

/* --- Report --- */
.k12-report { padding: 60px 0; }
.k12-report h1 {
  font-size: 32px; font-weight: 900; text-align: center; margin-bottom: 8px;
  color: var(--k12-text);
}
.k12-report-sub { text-align: center; color: var(--k12-light); font-size: 14px; margin-bottom: 40px; }

.k12-profile-bar {
  background: var(--k12-card); border: 1px solid var(--k12-border);
  border-radius: var(--k12-radius);
  padding: 24px 32px; margin-bottom: 32px;
  display: flex; justify-content: space-around; flex-wrap: wrap; gap: 16px;
  box-shadow: var(--k12-shadow);
}
.k12-profile-item { text-align: center; }
.k12-profile-label { font-size: 12px; color: var(--k12-light); margin-bottom: 4px; }
.k12-profile-value { font-size: 24px; font-weight: 900; color: var(--k12-accent); }
.k12-profile-value.purple { color: var(--k12-accent); }

.k12-subject-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px; }
.k12-subject-card {
  background: var(--k12-card); border: 1px solid var(--k12-border);
  border-radius: 14px; padding: 20px;
  border-left: 3px solid var(--card-color, #3b82f6);
  box-shadow: var(--k12-shadow);
}
.k12-subject-card h3 { font-size: 15px; font-weight: 700; margin-bottom: 8px; color: var(--k12-text); }
.k12-subject-card h3 .emoji { margin-right: 8px; }
.k12-subject-card .stat-row {
  display: flex; justify-content: space-between; font-size: 13px;
  padding: 3px 0; color: var(--k12-dim);
}
.k12-subject-card .stat-row .val { color: var(--k12-text); font-weight: 600; }
.k12-subject-card .last-summary {
  margin-top: 10px; padding-top: 10px;
  border-top: 1px solid var(--k12-border);
  font-size: 12px; color: var(--k12-dim); line-height: 1.6;
}

/* --- K12 Nav Link --- */
.topbar-links a[href="#k12"] {
  color: var(--k12-accent) !important;
  font-weight: 700;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .k12-hero h1 { font-size: 26px; }
  .k12-grid { grid-template-columns: 1fr; }
  .k12-classroom { flex-direction: column; }
  .k12-sidebar { width: 100%; flex-direction: row; padding: 12px 16px; gap: 12px; }
  .k12-sidebar-avatar { width: 50px; height: 50px; font-size: 24px; margin-bottom: 0; }
  .k12-sidebar h2 { font-size: 16px; }
  .k12-sidebar .k12-sidebar-info { display: none; }
  .k12-sidebar-actions { margin-top: 0; width: auto; display: flex; gap: 8px; }
  .k12-sidebar-actions button { width: auto; margin-top: 0; padding: 6px 12px; font-size: 12px; }
  .k12-chat-messages { padding: 16px; }
  .k12-chat-input-bar { padding: 12px 16px; }
  .k12-profile-bar { flex-direction: column; }
}