/* ===========================================
   Option Selector Method — Glassmorphism Redesign
   =========================================== */

/* ---------- Animations ---------- */
@keyframes os-fade-in {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes os-option-appear {
    from {
        opacity: 0;
        transform: translateX(-6px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes os-response-reveal {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ---------- Hide legacy corner frame ---------- */
.os-corner-node { display: none !important; }

/* ---------- Page wrapper (lesson-runner injects .module-option-selector as parent) ---------- */
.os-page,
.module-option-selector {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100vh;
    overflow: hidden;
    padding: 2rem;
    box-sizing: border-box;
    animation: os-fade-in 0.45s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* ---------- Glass Card (main container) ---------- */
.os-container {
    background: rgba(10, 7, 28, 0.82);
    backdrop-filter: blur(36px);
    -webkit-backdrop-filter: blur(36px);
    border: 1px solid rgba(130, 90, 255, 0.25);
    border-radius: 20px;
    box-shadow:
        0 20px 60px rgba(0, 0, 0, 0.6),
        0 0 0 1px rgba(255, 255, 255, 0.04) inset,
        0 1px 0 rgba(255, 255, 255, 0.08) inset,
        0 0 80px rgba(89, 0, 200, 0.08);
    padding: 2rem 2.5rem;
    width: 100%;
    max-width: 680px;
    max-height: calc(100vh - 80px);
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: rgba(130, 90, 255, 0.35) transparent;
    box-sizing: border-box;
    position: relative;
    border-image: none;
}

/* ---------- Progress indicator ---------- */
.os-progress {
    font-family: 'Poppins', sans-serif;
    font-size: 0.67rem;
    font-weight: 600;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    color: rgba(0, 217, 255, 0.55);
    margin-bottom: 1.5rem;
    text-align: center;
}

/* ---------- Question ---------- */
.os-question {
    font-family: 'Poppins', sans-serif;
    font-size: 1.05rem;
    font-weight: 500;
    line-height: 1.65;
    color: rgba(220, 215, 245, 0.95);
    text-align: left;
    margin-bottom: 1.75rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid rgba(130, 90, 255, 0.12);
    background: transparent;
    border-left: none;
    border-top: none;
    border-right: none;
}

.os-question h3 {
    font-family: 'Poppins', sans-serif;
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    color: rgba(0, 217, 255, 0.7);
    margin: 0 0 0.75rem;
}

.os-question p {
    margin: 0 0 0.5rem;
    color: rgba(200, 195, 230, 0.85);
    font-size: 0.96rem;
}

.os-question p:last-child { margin-bottom: 0; }

/* ---------- Text-style options (quiz mode) ---------- */
.os-options-text {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1.75rem;
}

.os-option-text {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(130, 90, 255, 0.15);
    border-radius: 12px;
    padding: 0.9rem 1.1rem 0.9rem 1.25rem;
    cursor: pointer;
    transition:
        background 0.2s ease,
        border-color 0.2s ease,
        transform 0.2s cubic-bezier(0.16, 1, 0.3, 1),
        box-shadow 0.2s ease;
    display: flex;
    align-items: center;
    gap: 0.9rem;
    text-align: left;
    position: relative;
    overflow: hidden;
    box-sizing: border-box;
    animation: os-option-appear 0.32s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* Stagger appearance */
.os-options-text .os-option-text:nth-child(1) { animation-delay: 0.04s; }
.os-options-text .os-option-text:nth-child(2) { animation-delay: 0.10s; }
.os-options-text .os-option-text:nth-child(3) { animation-delay: 0.16s; }
.os-options-text .os-option-text:nth-child(4) { animation-delay: 0.22s; }
.os-options-text .os-option-text:nth-child(5) { animation-delay: 0.28s; }

/* Radio circle — replaces ::before */
.os-option-text::before {
    content: '';
    width: 16px;
    height: 16px;
    border: 1.5px solid rgba(130, 90, 255, 0.4);
    border-radius: 50%;
    flex-shrink: 0;
    transition: all 0.2s ease;
    background: transparent;
}

/* Left accent bar */
.os-option-text::after {
    content: '';
    position: absolute;
    left: 0;
    top: 10%;
    height: 80%;
    width: 2.5px;
    background: rgba(130, 90, 255, 0.6);
    border-radius: 0 2px 2px 0;
    transform: scaleY(0);
    transition: transform 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.os-option-text:hover {
    background: rgba(130, 90, 255, 0.08);
    border-color: rgba(130, 90, 255, 0.38);
    transform: translateX(3px);
}

.os-option-text:hover::after {
    transform: scaleY(1);
}

.os-option-text.selected {
    background: rgba(130, 90, 255, 0.13);
    border-color: rgba(130, 90, 255, 0.5);
    transform: translateX(3px);
    box-shadow: 0 2px 16px rgba(130, 90, 255, 0.12);
}

.os-option-text.selected::before {
    background: rgba(130, 90, 255, 0.85);
    border-color: rgba(130, 90, 255, 0.9);
    box-shadow: 0 0 8px rgba(130, 90, 255, 0.5);
}

.os-option-text.selected::after {
    transform: scaleY(1);
}

.os-option-text .os-option-label {
    font-family: 'Poppins', sans-serif;
    font-size: 0.94rem;
    font-weight: 400;
    color: rgba(210, 205, 238, 0.88);
    line-height: 1.5;
    transition: color 0.2s;
}

.os-option-text.selected .os-option-label {
    color: rgba(230, 225, 255, 1);
    font-weight: 500;
}

/* ---------- Card-style options (icon grid mode) ---------- */
.os-options-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.75rem;
    justify-content: center;
}

.os-option {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(130, 90, 255, 0.18);
    border-radius: 14px;
    padding: 1.25rem 1.5rem;
    cursor: pointer;
    transition:
        background 0.2s ease,
        border-color 0.2s ease,
        transform 0.2s cubic-bezier(0.16, 1, 0.3, 1),
        box-shadow 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    text-align: center;
    user-select: none;
    flex: 0 1 30%;
    min-width: 160px;
    max-width: 280px;
    box-sizing: border-box;
    position: relative;
    animation: os-option-appear 0.32s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.os-option:hover {
    background: rgba(130, 90, 255, 0.1);
    border-color: rgba(130, 90, 255, 0.4);
    transform: translateY(-3px);
    box-shadow: 0 6px 24px rgba(130, 90, 255, 0.15);
}

.os-option.selected {
    background: rgba(130, 90, 255, 0.18);
    border-color: rgba(130, 90, 255, 0.6);
    box-shadow: 0 0 0 1px rgba(130, 90, 255, 0.3), 0 4px 20px rgba(130, 90, 255, 0.18);
    animation: none;
    transform: translateY(-2px);
}

.os-option.selected::after {
    content: '✓';
    position: absolute;
    top: 8px;
    right: 10px;
    font-size: 0.72rem;
    color: rgba(130, 90, 255, 0.9);
    font-family: 'Poppins', sans-serif;
}

.os-option-icon {
    font-size: 1.8rem;
    line-height: 1;
}

.os-option-label {
    font-family: 'Poppins', sans-serif;
    font-size: 0.88rem;
    font-weight: 500;
    color: rgba(210, 205, 238, 0.85);
    line-height: 1.4;
}

.os-option.selected .os-option-label {
    color: #fff;
}

/* ---------- Response / Feedback area ---------- */
.os-response-area {
    background: rgba(130, 90, 255, 0.07);
    border: 1px solid rgba(130, 90, 255, 0.22);
    border-radius: 14px;
    padding: 1.25rem 1.5rem;
    margin-top: 1rem;
    margin-bottom: 1rem;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.3s ease, transform 0.3s ease;
    font-family: 'Poppins', sans-serif;
    font-size: 0.92rem;
    color: rgba(210, 205, 238, 0.9);
    line-height: 1.65;
}

.os-response-area.active {
    opacity: 1;
    transform: translateY(0);
    animation: os-response-reveal 0.35s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.os-response-area p { margin: 0 0 0.6rem; }
.os-response-area p:last-child { margin-bottom: 0; }

.os-divider {
    border: none;
    border-top: 1px solid rgba(130, 90, 255, 0.15);
    margin: 0.75rem 0;
}

.os-synthesis-header {
    font-family: 'Poppins', sans-serif;
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: rgba(0, 217, 255, 0.7);
    text-align: center;
    margin-bottom: 0.6rem;
}

.os-synthesis-body {
    text-align: center;
    font-size: 0.9rem;
}

/* ---------- Confirm / Next button ---------- */
.os-btn-wrapper {
    text-align: center;
    margin-top: 1.5rem;
}

/* Override .btn .btn-primary with our design */
.os-confirm-btn,
.btn.btn-primary.os-confirm-btn {
    display: inline-block;
    min-width: 160px;
    padding: 0.72rem 2.5rem;
    background: transparent;
    border: 1.5px solid rgba(0, 217, 255, 0.5);
    border-radius: 100px;
    color: #fff;
    font-family: 'Poppins', sans-serif;
    font-size: 0.78rem;
    font-weight: 500;
    letter-spacing: 2.5px;
    text-transform: uppercase;
    cursor: pointer;
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: 0 0 16px rgba(0, 217, 255, 0.1);
}

.os-confirm-btn:disabled,
.btn.btn-primary.os-confirm-btn:disabled {
    opacity: 0.32;
    cursor: not-allowed;
    transform: none !important;
    box-shadow: none !important;
}

.os-confirm-btn:not(:disabled):hover,
.btn.btn-primary.os-confirm-btn:not(:disabled):hover {
    background: rgba(0, 217, 255, 0.1);
    border-color: rgba(0, 217, 255, 0.85);
    box-shadow: 0 0 24px rgba(0, 217, 255, 0.28);
    transform: translateY(-1px);
}

.os-confirm-btn:not(:disabled):active {
    transform: translateY(0);
    box-shadow: 0 0 12px rgba(0, 217, 255, 0.15);
}

/* Success state (correct answer confirmed) */
.os-confirm-btn.btn-success {
    border-color: rgba(0, 217, 150, 0.6);
    box-shadow: 0 0 20px rgba(0, 217, 150, 0.18);
}

.os-confirm-btn.btn-success:not(:disabled):hover {
    background: rgba(0, 217, 150, 0.1);
    border-color: rgba(0, 217, 150, 0.85);
    box-shadow: 0 0 28px rgba(0, 217, 150, 0.28);
}

/* ---------- Correct / Incorrect answer feedback ---------- */
@keyframes os-correct-glow {
    0%   { box-shadow: 0 0 0 2px rgba(0, 220, 130, 0.8), 0 0 24px rgba(0, 220, 130, 0.45); background: rgba(0, 220, 130, 0.2); }
    100% { box-shadow: 0 2px 16px rgba(130, 90, 255, 0.12); background: rgba(130, 90, 255, 0.13); }
}

@keyframes os-incorrect-shake {
    0%  { transform: translateX(0); }
    15% { transform: translateX(-7px); }
    30% { transform: translateX(6px); }
    45% { transform: translateX(-5px); }
    60% { transform: translateX(4px); }
    75% { transform: translateX(-2px); }
    100% { transform: translateX(0); }
}

.os-option-text.os-answer-correct {
    border-color: rgba(0, 220, 130, 0.7) !important;
    color: #fff !important;
    animation: os-correct-glow 1.4s ease-out forwards;
}

.os-option-text.os-answer-correct::before {
    background: rgba(0, 220, 130, 0.9) !important;
    border-color: rgba(0, 220, 130, 1) !important;
    box-shadow: 0 0 10px rgba(0, 220, 130, 0.6) !important;
}

.os-option-text.os-answer-incorrect {
    border-color: rgba(255, 80, 80, 0.65) !important;
    background: rgba(255, 80, 80, 0.1) !important;
    animation: os-incorrect-shake 0.45s ease-in-out;
}

.os-option-text.os-answer-incorrect::before {
    background: rgba(255, 80, 80, 0.75) !important;
    border-color: rgba(255, 80, 80, 0.9) !important;
}

/* Response area tint based on outcome */
.os-response-area.os-response-correct {
    background: rgba(0, 200, 120, 0.07);
    border-color: rgba(0, 200, 120, 0.28);
}

.os-response-area.os-response-incorrect {
    background: rgba(255, 80, 80, 0.06);
    border-color: rgba(255, 80, 80, 0.22);
}

/* Brighter quiz option text */
.os-option-text .os-option-label {
    font-family: 'Poppins', sans-serif;
    font-size: 0.94rem;
    font-weight: 400;
    color: rgba(232, 228, 255, 0.92);
    line-height: 1.5;
    transition: color 0.2s;
}

.os-option-text.selected .os-option-label {
    color: rgba(240, 236, 255, 1);
    font-weight: 500;
}

/* ---------- Responsive ---------- */
@media (max-width: 640px) {
    .os-page {
        padding: 1.5rem 1rem;
        align-items: flex-start;
        padding-top: 2rem;
    }

    .os-container {
        padding: 1.75rem 1.5rem;
        border-radius: 16px;
    }

    .os-question { font-size: 0.97rem; }
    .os-option-text { padding: 0.8rem 1rem; }
    .os-option-text .os-option-label { font-size: 0.9rem; }
}