:root{--classroom-bg-0:#06111f;--classroom-bg-1:#091a33;--classroom-bg-2:#0c2240;--classroom-surface-0:#071226db;--classroom-surface-1:#0c1830eb;--classroom-surface-2:#101e3af5;--classroom-border-soft:#ffffff14;--classroom-border-mid:#7ee3ff38;--classroom-border-strong:#7ee3ff52;--classroom-text-strong:#f7fbff;--classroom-text:#e8eff9eb;--classroom-text-soft:#e8eff9c2;--classroom-text-dim:#e8eff99e;--classroom-glow-blue:#58a4ff38;--classroom-glow-cyan:#7ee3ff2e;--classroom-glow-green:#2eb57d2e;--classroom-chip-bg:#ffffff14;--classroom-chip-border:#ffffff1a;--classroom-btn-bg:linear-gradient(135deg,#5f88ff 0%,#7fa8ff 100%);--classroom-btn-border:#7ee3ff57;--classroom-btn-ghost-bg:#ffffff08;--classroom-radius-xl:28px;--classroom-radius-lg:22px;--classroom-radius-md:18px;--classroom-radius-sm:14px;--classroom-shadow-lg:0 24px 70px #0000003d;--classroom-shadow-md:0 12px 36px #00000038}
.classroom-shell{border-radius:var(--classroom-radius-xl);border:1px solid var(--classroom-border-soft);box-shadow:var(--classroom-shadow-lg);background:radial-gradient(circle at 50% 0,#679dff2e,#0000 26%),linear-gradient(#09162cf5 0%,#050e1efa 100%);position:relative;overflow:hidden}.classroom-grid{grid-template-columns:180px minmax(0,1fr) 210px;align-items:start;gap:14px;display:grid}@media (max-width:1100px){.classroom-grid{grid-template-columns:160px minmax(0,1fr) 180px}}@media (max-width:900px){.classroom-grid{grid-template-columns:1fr}}
.classroom-rail{border-radius:var(--classroom-radius-lg);border:1px solid var(--classroom-border-soft);box-shadow:var(--classroom-shadow-md);background:linear-gradient(#08162ff0 0%,#040d1dfa 100%);padding:14px}.classroom-rail-section-label{letter-spacing:.12em;text-transform:uppercase;color:var(--classroom-text-dim);margin:0 0 12px;font-size:12px;line-height:1}.classroom-rail-stack{gap:10px;display:grid}.classroom-rail-button{border:1px solid var(--classroom-border-strong);width:100%;min-height:46px;color:var(--classroom-text-strong);background:#ffffff05;border-radius:18px;box-shadow:inset 0 1px #ffffff0a}.classroom-rail-button.is-active{color:#fff;background:linear-gradient(135deg,#5b7efff2 0%,#7cadffeb 100%);border-color:#98c4ff8c}.classroom-focus-review{border-top:1px solid #ffffff14;margin-top:18px;padding-top:18px}
.classroom-board,.classroom-answer-panel{border-radius:var(--classroom-radius-xl);border:1px solid var(--classroom-border-soft);box-shadow:var(--classroom-shadow-lg)}.classroom-board{background:radial-gradient(circle at 50% 20%,var(--classroom-glow-green),transparent 34%),linear-gradient(180deg,#072921e0 0%,#041414f5 100%)}.classroom-question-card{border-radius:var(--classroom-radius-lg);color:var(--classroom-text-strong);background:#ffffff08;border:1px solid #ffffff14}.classroom-answer-panel{background:radial-gradient(circle at 50% 10%,var(--classroom-glow-blue),transparent 34%),linear-gradient(180deg,#15234af5 0%,#071024fa 100%)}.classroom-answer-choice{color:var(--classroom-text-strong);background:#ffffff08;border:1px solid #ffffff14;border-radius:18px}.classroom-answer-choice.is-selected{background:#7ee3ff1a;border-color:#7ee3ff4d}.classroom-answer-choice.is-correct{background:#3ea05824;border-color:#3ea05857}.classroom-answer-choice.is-incorrect{background:#ff78781a;border-color:#ff78784d}
.classroom-side-card{border-radius:var(--classroom-radius-lg);border:1px solid var(--classroom-border-soft);box-shadow:var(--classroom-shadow-md);background:linear-gradient(#09152cf2 0%,#050d1cfa 100%)}.classroom-chip{border:1px solid var(--classroom-chip-border);background:var(--classroom-chip-bg);min-height:32px;color:var(--classroom-text-strong);border-radius:999px;justify-content:center;align-items:center;padding:0 12px;display:inline-flex}
.classroom-action-row{flex-wrap:wrap;align-items:center;gap:10px;display:flex}.classroom-btn{border:1px solid var(--classroom-btn-border);min-height:40px;color:var(--classroom-text-strong);border-radius:16px;padding:0 16px}.classroom-btn-primary{background:var(--classroom-btn-bg);box-shadow:0 10px 30px #5f88ff42}.classroom-btn-ghost{background:var(--classroom-btn-ghost-bg)}.classroom-btn:disabled,.classroom-btn[aria-disabled=true]{opacity:.45;cursor:not-allowed;box-shadow:none}