/* --- (MỚI) THEME PASTEL (SÁNG) --- */
:root {
    --bg-main: #F8F7FF;
    --bg-card: #FFFFFF;
    --border-color: #E0E0E0;
    --text-primary: #2D3748;
    --text-secondary: #718096;
    --pastel-primary: #7C3AED;
    --pastel-secondary: #3B82F6;
    --ai-bubble-bg: #F3F4F6;
    --ai-bubble-text: #374151;
    --user-bubble-bg: linear-gradient(to right, #8B5CF6, #6366F1);
    --user-bubble-text: #FFFFFF;
}

/* --- Nền tảng & Font chữ --- */
body {
    font-family: 'Be Vietnam Pro', sans-serif;
    background-color: var(--bg-main);
    color: var(--text-primary);
    overflow-x: hidden;
}
.gradient-text {
    background: linear-gradient(to right, var(--pastel-primary), var(--pastel-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.gradient-bg {
     background: var(--user-bubble-bg);
     color: var(--user-bubble-text);
     transition: all 0.3s ease-in-out;
}
.gradient-bg:hover {
    opacity: 0.9;
    box-shadow: 0 0 15px rgba(139, 92, 246, 0.4);
}
.background-aura {
    position: fixed; 
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(196, 181, 253, 0.2) 0%, rgba(247, 247, 255, 0) 70%);
    z-index: -10;
}

/* --- Header --- */
header {
    background-color: rgba(255, 255, 255, 0.8) !important;
    backdrop-filter: blur(10px) !important;
    border-bottom-color: var(--border-color) !important;
}
header nav a {
    color: var(--text-secondary) !important;
}
header nav a:hover {
    background-color: #F3F4F6 !important;
    color: var(--text-primary) !important;
}
header nav a.gradient-bg { /* Link Active (Tối ưu công thái học) */
    color: var(--user-bubble-text) !important;
    box-shadow: 0 0 15px rgba(139, 92, 246, 0.4);
}
header button#mobile-menu-btn {
    color: var(--text-primary) !important;
}
#mobile-menu {
    background-color: var(--bg-card) !important;
    border-top-color: var(--border-color) !important;
}
#mobile-menu a.bg-slate-800 {
    background-color: #EDE9FE !important;
    color: var(--pastel-primary) !important;
    font-weight: 600 !important;
}

/* --- (MỚI) FEATURE CARDS STYLING (GIỐNG GRADE CARDS) --- */

/* Base styling */
.feature-card {
    background-color: var(--bg-card);
    border: 2px solid;
    border-radius: 1rem;
    padding: 1.75rem 2rem;
    transition: all 0.3s ease-in-out;
    display: flex;
    flex-direction: column;
    min-height: 320px;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

/* Card-specific backgrounds and borders */
.feature-card-1 {
    background-color: #E0F7FF;
    border-color: #00D4FF;
}

.feature-card-1:hover {
    background-color: #C5F3FF;
    border-color: #0099CC;
}

.feature-card-2 {
    background-color: #FFF0FF;
    border-color: #FF00FF;
}

.feature-card-2:hover {
    background-color: #FFE6FF;
    border-color: #DD00DD;
}

.feature-card-3 {
    background-color: #E0FFF0;
    border-color: #00FF99;
}

.feature-card-3:hover {
    background-color: #C5FFEE;
    border-color: #00CC66;
}

.feature-card-4 {
    background-color: #FFFBE6;
    border-color: #FFD700;
}

.feature-card-4:hover {
    background-color: #FFFACC;
    border-color: #FFAA00;
}

/* Icon styling */
.feature-card-icon {
    width: 4rem;
    height: 4rem;
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.25rem;
    flex-shrink: 0;
    color: white;
    font-weight: 600;
}

.feature-card-icon.bg-cyan-500 {
    background: linear-gradient(135deg, #00D4FF, #0099CC);
    color: white;
}

.feature-card-icon.bg-fuchsia-500 {
    background: linear-gradient(135deg, #FF00FF, #DD00DD);
    color: white;
}

.feature-card-icon.bg-emerald-500 {
    background: linear-gradient(135deg, #00FF99, #00CC66);
    color: white;
}

.feature-card-icon.bg-amber-500 {
    background: linear-gradient(135deg, #FFD700, #FFAA00);
    color: #333;
}

/* Title and description */
.feature-card-title {
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    line-height: 1.4;
}

.feature-card-desc {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

/* Button styling */
.feature-card-button {
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
    padding: 0.65rem 1.5rem;
    border-radius: 0.5rem;
    display: inline-block;
    text-align: center;
    transition: all 0.3s ease-in-out;
    border: none;
    cursor: pointer;
    text-decoration: none;
    align-self: flex-start;
    margin-top: auto;
}

.feature-card-button:hover {
    transform: scale(1.05) translateY(-2px);
    opacity: 0.95;
}

/* Button gradient colors (matching cards) */
.button-feature-1 {
    background: linear-gradient(to right, #00D4FF, #0099CC);
    box-shadow: 0 4px 15px rgba(0, 212, 255, 0.3);
}

.button-feature-1:hover {
    background: linear-gradient(to right, #00E6FF, #0088BB);
    box-shadow: 0 6px 20px rgba(0, 212, 255, 0.4);
}

.button-feature-2 {
    background: linear-gradient(to right, #FF00FF, #DD00DD);
    box-shadow: 0 4px 15px rgba(255, 0, 255, 0.3);
}

.button-feature-2:hover {
    background: linear-gradient(to right, #FF33FF, #CC00CC);
    box-shadow: 0 6px 20px rgba(255, 0, 255, 0.4);
}

.button-feature-3 {
    background: linear-gradient(to right, #00FF99, #00CC66);
    box-shadow: 0 4px 15px rgba(0, 255, 153, 0.3);
}

.button-feature-3:hover {
    background: linear-gradient(to right, #33FFAA, #00BB55);
    box-shadow: 0 6px 20px rgba(0, 255, 153, 0.4);
}

.button-feature-4 {
    background: linear-gradient(to right, #FFD700, #FFAA00);
    color: #333;
    box-shadow: 0 4px 15px rgba(255, 215, 0, 0.3);
}

.button-feature-4:hover {
    background: linear-gradient(to right, #FFE633, #FF9900);
    color: #333;
    box-shadow: 0 6px 20px rgba(255, 215, 0, 0.4);
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .feature-card {
        padding: 1.5rem 1.25rem;
        min-height: auto;
    }

    .feature-card-icon {
        width: 3.5rem;
        height: 3.5rem;
    }

    .feature-card-title {
        font-size: 1.1rem;
    }

    .feature-card-desc {
        font-size: 0.9rem;
    }

    .feature-card-button {
        padding: 0.6rem 1.25rem;
        font-size: 0.85rem;
    }
}

/* Animation for fade-in-on-scroll */
.feature-card.fade-in-on-scroll {
    opacity: 0;
    animation: fadeInUp 0.6s ease-out forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --- (TỐI ƯU) Tô màu Grade Cards (Khối 10, 11, 12) --- */
.grade-card {
    padding: 1.5rem 2rem;
}
.grade-card:has(.text-cyan-400), #grade-10 {
    background-color: #FFF3E0;
    border-color: #FFB74D;
}
.grade-card:has(.text-fuchsia-400), #grade-11 {
    background-color: #FFFDE7;
    border-color: #FFD54F;
}
.grade-card:has(.text-emerald-400), #grade-12 {
    background-color: #FCE4EC;
    border-color: #F06292;
}
.grade-card-number {
    font-weight: 800;
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
    display: block;
}
.grade-card-number.text-cyan-400 { color: #F57C00 !important; }
.grade-card-number.text-fuchsia-400 { color: #FBC02D !important; }
.grade-card-number.text-emerald-400 { color: #E91E63 !important; }

/* --- (TỐI ƯU NHẤT) Nút "Bắt Đầu" Gradient (Giống ảnh mẫu) --- */
.grade-card-button {
    color: white;
    font-weight: 600;
    font-size: 0.875rem;
    padding: 0.6rem 1.25rem;
    border-radius: 0.5rem;
    display: inline-block;
    margin-top: 1rem;
    transition: all 0.3s ease-in-out;
    border: none;
}
.grade-card-button:hover {
    transform: scale(1.05) translateY(-2px);
    opacity: 0.9;
}
.button-10 {
    background: linear-gradient(to right, #fbbf24, #f97316);
    box-shadow: 0 4px 15px rgba(249, 115, 22, 0.3);
}
.button-11 {
    background: linear-gradient(to right, #fde047, #facc15);
    box-shadow: 0 4px 15px rgba(250, 204, 21, 0.4);
    color: #422006;
}
.button-12 {
    background: linear-gradient(to right, #f472b6, #ec4899);
    box-shadow: 0 4px 15px rgba(236, 72, 153, 0.3);
}


/* --- Form Input --- */
.form-input {
    background-color: var(--bg-card);
    border: 1px solid #CBD5E0;
    color: var(--text-primary);
    border-radius: 0.5rem;
    padding: 0.75rem 1rem;
    width: 100%;
    transition: all 0.3s ease;
    font-family: 'Be Vietnam Pro', sans-serif;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Cpath stroke='%23718096' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3E%3C/svg%3E");
    background-position: right 0.5rem center;
    background-repeat: no-repeat;
    background-size: 1.5em 1.5em;
    padding-right: 2.5rem;
}
.form-input:focus {
    outline: none;
    border-color: var(--pastel-primary);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.3);
}
.form-input::placeholder { color: var(--text-secondary); }
.form-input[type="datetime-local"]::-webkit-calendar-picker-indicator { display: none; }
a.text-indigo-400 { color: var(--pastel-primary) !important; }
a.text-indigo-400:hover { background-color: #F5F3FF !important; }

/* --- CSS CHO GIAO DIỆN CHAT, QUIZ, MODAL (Theme Sáng) --- */
div[style*="background-color: #1A1A2E"],
.rounded-xl {
    background-color: var(--bg-card) !important;
    border-color: var(--border-color) !important;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
}
.border-b.border-slate-700, .border-t.border-slate-700,
.border-b, .border-t {
    border-color: var(--border-color) !important;
}
#chat-window { color: var(--text-primary); }
p.text-slate-400 { color: var(--text-secondary) !important; }
p.text-cyan-300 { color: var(--pastel-secondary) !important; }
p.text-slate-200 { color: var(--text-primary) !important; }
p.text-slate-300 { color: var(--text-primary) !important; }
p.text-slate-500 { color: var(--text-secondary) !important; }

/*
--- (SỬA LỖI MODAL TRONG SUỐT) ---
Thêm màu nền cho 2 cửa sổ Modal
*/
#modal-content, #dictionary-modal-content {
    background-color: var(--bg-card) !important; 
    border: 1px solid var(--border-color);
}

/* Modal Colors */
#modal-content h2, #dictionary-modal-content h2 { color: var(--text-primary); }
#modal-content p, #dictionary-modal-content p,
#modal-content h3, #dictionary-modal-content h3,
#modal-content span, #dictionary-modal-content span {
    color: var(--text-primary);
}
#modal-content p.text-slate-400, #dictionary-modal-content p.text-slate-400 {
    color: var(--text-secondary) !important;
}
#modal-content #question-text {
    background-color: var(--bg-main);
    border-color: var(--border-color);
    color: var(--pastel-secondary);
}
#modal-content #transcript-text {
    background-color: var(--bg-main);
    border-color: var(--border-color);
}
#modal-content #feedback-suggestion {
    background-color: var(--bg-main);
}
#modal-content #tab-btn-question.active {
    color: var(--pastel-primary) !important;
    border-color: var(--pastel-primary) !important;
}
#modal-content .tab-btn {
    color: var(--text-secondary);
}
#modal-content #prev-btn {
    background-color: #F3F4F6;
    color: var(--text-secondary);
}
#modal-content #prev-btn:hover { background-color: #E5E7EB; }
#dictionary-modal-content #dict-ipa { color: var(--pastel-primary); }
#dictionary-modal-content #dict-definition { background-color: var(--bg-main); }

/* Bong bóng chat */
.chat-bubble { display: flex; max-width: 90%; gap: 0.75rem; animation: pop-in 0.3s ease-out forwards; }
@keyframes pop-in {
    from { opacity: 0; transform: translateY(10px) scale(0.95); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}
.chat-avatar { width: 2.5rem; height: 2.5rem; border-radius: 9999px; display: flex; align-items: center; justify-content: center; font-weight: 600; flex-shrink: 0; }
.chat-content { padding: 0.75rem 1rem; border-radius: 1rem; width: 100%; }
.ai-bubble { margin-right: auto; }
.ai-bubble .chat-avatar { background-color: #E0E7FF; color: #4338CA; }
.ai-bubble .chat-content { background-color: var(--ai-bubble-bg); color: var(--ai-bubble-text); border-bottom-left-radius: 0.25rem; display: flex; justify-content: space-between; align-items: center; gap: 1rem; }
.ai-bubble .play-audio-btn { background: none; border: none; color: var(--text-secondary); padding: 0; margin: 0; cursor: pointer; transition: all 0.2s ease; flex-shrink: 0; }
.ai-bubble .play-audio-btn:hover { color: var(--pastel-secondary); }
.ai-bubble .play-audio-btn.playing i { color: var(--pastel-secondary); animation: pulse-icon 1s infinite; }
@keyframes pulse-icon { 0%, 100% { opacity: 1; } 50% { opacity: 0.6; } }

.user-bubble { margin-left: auto; flex-direction: row-reverse; }
.user-bubble .chat-avatar { background-color: #EDE9FE; color: var(--pastel-primary); }
.user-bubble .chat-content { background: var(--user-bubble-bg); color: var(--user-bubble-text); border-bottom-right-radius: 0.25rem; }
.user-bubble .message-text { font-size: 1.125rem; font-weight: 500; }
.user-bubble .show-feedback-btn { background: rgba(255, 255, 255, 0.2); border: none; color: #ffffff; padding: 0.25rem 0.75rem; border-radius: 9999px; margin-top: 0.75rem; font-size: 0.875rem; font-weight: 500; cursor: pointer; transition: all 0.2s ease; }
.user-bubble .show-feedback-btn:hover { background: rgba(255, 255, 255, 0.3); }

/* Feedback Panel */
.feedback-panel { margin-top: 1rem; padding-top: 1rem; border-top: 1px solid rgba(255, 255, 255, 0.3); display: flex; align-items: stretch; gap: 1rem; }
.feedback-score { flex-shrink: 0; width: 5rem; height: 5rem; border-radius: 9999px; display: flex; flex-direction: column; align-items: center; justify-content: center; background: rgba(0, 0, 0, 0.2); }
.feedback-score .score-text { font-size: 1.875rem; font-weight: 800; }
.feedback-score .score-label { font-size: 0.75rem; font-weight: 500; opacity: 0.8; }
.score-good { background: rgba(22, 163, 74, 0.8); }
.score-medium { background: rgba(202, 138, 4, 0.8); }
.score-bad { background: rgba(220, 38, 38, 0.8); }

.feedback-details { flex: 1; display: flex; flex-direction: column; gap: 0.75rem; font-size: 0.875rem; }

/* (SỬA LỖI BUG 1) Cải thiện hiển thị Feedback */
.feedback-details .transcript-text {
    background: rgba(0, 0, 0, 0.2);
    padding: 0.5rem 0.75rem;
    border-radius: 0.5rem;
    word-wrap: break-word; /* Đảm bảo text dài tự xuống dòng */
}
.feedback-details .transcript-text strong {
    opacity: 0.8;
}
.feedback-details .transcript-text span {
    /* (Sửa lỗi) Không dùng 'block' nữa, 
       để 'break-words' trên div cha tự xử lý */
    font-style: italic;
}

.feedback-audio-controls { display: flex; gap: 0.5rem; }
.feedback-audio-controls button { flex: 1; background: rgba(0, 0, 0, 0.2); border: none; color: #ffffff; padding: 0.5rem; border-radius: 0.5rem; font-size: 0.875rem; font-weight: 500; cursor: pointer; transition: all 0.2s ease; display: flex; align-items: center; justify-content: center; gap: 0.25rem; }
.feedback-audio-controls button:hover { background: rgba(0, 0, 0, 0.4); }

/* (TÍNH NĂNG MỚI) Thêm class cho IPA (hiện chưa dùng) */
.ipa-feedback-container {
    margin-top: 0.75rem;
    padding-top: 0.75rem;
    border-top: 1px solid rgba(255, 255, 255, 0.3);
}
.ipa-feedback {
    font-family: monospace;
    font-size: 1.1rem;
    font-weight: 500;
    line-height: 1.6;
}
.ipa-correct {
    color: #86efac; /* green-300 */
}
.ipa-incorrect {
    color: #fca5a5; /* red-300 */
    text-decoration: line-through;
}

/* --- Nút Ghi âm (Cả hai trang) --- */
.dialogue-record-btn, #record-btn {
    background: var(--user-bubble-bg);
    color: white;
    border-radius: 9999px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 14px rgba(139, 92, 246, 0.4);
    transition: all 0.3s ease-in-out;
    position: relative;
    border: none;
    cursor: pointer;
}
.dialogue-record-btn { width: 5rem; height: 5rem; margin-left: auto; margin-right: auto; }
#record-btn { width: 5rem; height: 5rem; } /* 80px */

.dialogue-record-btn:hover, #record-btn:hover {
    transform: scale(1.05);
}
.dialogue-record-btn:disabled, #record-btn:disabled {
    background: #CBD5E0;
    cursor: not-allowed;
    box-shadow: none;
}
.dialogue-record-btn .pulse-ring, #record-btn .pulse-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    background: var(--user-bubble-bg);
    border-radius: 9999px;
    opacity: 0;
    transition: all 0.3s ease;
}
.dialogue-record-btn.recording-active, #record-btn.recording {
    background: #dc2626;
    box-shadow: 0 4px 14px #dc262670;
}
.dialogue-record-btn.recording-active .pulse-ring, #record-btn.recording .pulse-ring {
    animation: pulse-animation 1.5s infinite;
    background: #dc2626;
}
@keyframes pulse-animation {
    0% { transform: scale(1); opacity: 0.5; }
    100% { transform: scale(1.4); opacity: 0; }
}
.dialogue-record-btn #record-icon-container, #record-btn #record-icon-container {
    position: relative;
    z-index: 10;
}

/* --- Loader (Theme Sáng) --- */
.loader {
    border: 4px solid #E2E8F0;
    border-top: 4px solid var(--pastel-secondary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* --- Footer --- */
footer { border-top-color: var(--border-color) !important; }
footer p { color: var(--text-secondary) !important; }

/* Quiz Results Circle */
#score-progress-circle { color: var(--pastel-primary) !important; }
.text-slate-700 { color: #E2E8F0 !important; }
.bg-slate-700 {
    background-color: #F3F4F6 !important;
    color: var(--text-secondary) !important;
}
.bg-slate-700:hover { background-color: #E5E7EB !important; }

/*
--- (SỬA LỖI MÀU CHỮ main.js) ---
Phần này dùng để "đè" (override) các class màu chữ (text-white, text-slate-400)
mà file main.js đang tự động chèn vào khi vẽ card Unit.
*/
#topics-container .topic-card h3 {
    color: var(--text-primary) !important;
}
#topics-container .topic-card p {
    color: var(--text-secondary) !important;
}
/* (SỬA LỖI) Thêm hiệu ứng cho card Unit */
#topics-container .topic-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border-radius: 1rem;
    transition: all 0.3s ease-in-out; 
}
#topics-container .topic-card:hover {
    border-color: var(--pastel-primary);
    transform: translateY(-8px);
    box-shadow: 0 12px 35px rgba(167, 139, 250, 0.3);
}
#topics-container .topic-card-icon {
    background-color: #EDE9FE !important; /* Tím pastel */
    color: var(--pastel-primary) !important;
}

/* ... (toàn bộ code cũ của bạn giữ nguyên) ... */

/*
--- (SỬA LỖI MÀU CHỮ main.js) ---
Phần này dùng để "đè" (override) các class màu chữ (text-white, text-slate-400)
mà file main.js đang tự động chèn vào khi vẽ card Unit.
*/
#topics-container .topic-card h3 {
    color: var(--text-primary) !important;
}
#topics-container .topic-card p {
    color: var(--text-secondary) !important;
}
/* (SỬA LỖI) Thêm hiệu ứng cho card Unit */
#topics-container .topic-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border-radius: 1rem;
    transition: all 0.3s ease-in-out; 
}
#topics-container .topic-card:hover {
    border-color: var(--pastel-primary);
    transform: translateY(-8px);
    box-shadow: 0 12px 35px rgba(167, 139, 250, 0.3);
}
#topics-container .topic-card-icon {
    background-color: #EDE9FE !important; /* Tím pastel */
    color: var(--pastel-primary) !important;
}

/* --- (MỚI) SỬA LỖI MÀU CHỮ CHO QUIZ FEEDBACK --- */
.quiz-feedback-box {
    padding: 1rem;
    border-radius: 0.5rem;
    margin-top: 1rem;
    margin-bottom: 1rem;
    font-size: 1.125rem; /* 18px */
    font-weight: 500;
    line-height: 1.6;
}
/* Hộp Báo Lỗi (Màu đỏ) */
.quiz-feedback-error {
    background-color: #FCE4EC; /* Hồng pastel (giống card 12) */
    border: 1px solid #F06292;
    color: #AD1457; /* Chữ hồng đậm */
}
.quiz-feedback-error strong {
    color: #880E4F; /* Chữ hồng siêu đậm (cho đáp án) */
}
/* Hộp Báo Đúng (Màu xanh) */
.quiz-feedback-correct {
    background-color: #E8F5E9; /* Xanh lá pastel */
    border: 1px solid #81C784;
    color: #2E7D32; /* Chữ xanh đậm */
}