:root {
    --primary: #DE1153; 
    --primary-hover: #B80C42;
    --primary-light: #FFF0F4;
    --background: #FAFAFA;
    --surface: #FFFFFF;
    --text-main: #2D2D2D;
    --text-muted: #666666;
    --border: #EAEAEA;
    --shadow: rgba(222, 17, 83, 0.06);
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Plus Jakarta Sans', 'Sarabun', sans-serif;
    background-color: var(--background);
    color: var(--text-main);
    line-height: 1.6;
    padding-bottom: 60px;
}

.navbar {
    background-color: var(--surface);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0,0,0,0.02);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 22px;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo::before {
    content: ' ';
    display: inline-block;
    width: 12px;
    height: 12px;
    background-color: var(--primary);
    border-radius: 50%;
}

.btn {
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-size: 14px;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-outline {
    background-color: transparent;
    border: 1px solid var(--primary);
    color: var(--primary);
}

.btn-outline:hover {
    background-color: var(--primary-light);
}

.main-header {
    max-width: 700px;
    margin: 40px auto 30px;
    padding: 0 20px;
    text-align: center;
}

.main-header h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -0.5px;
}

.search-wrapper {
    position: relative;
    margin-top: 25px;
    box-shadow: 0 10px 25px var(--shadow);
    border-radius: var(--radius-md);
}

.search-input {
    width: 100%;
    padding: 16px 20px 16px 50px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    font-size: 16px;
    outline: none;
    transition: var(--transition);
    font-family: inherit;
}

.search-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.search-icon {
    position: absolute;
    left: 20px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    pointer-events: none;
}

.filter-container {
    max-width: 1200px;
    margin: 0 auto 30px;
    padding: 0 20px;
    display: flex;
    flex-wrap: wrap; /* ✨ หัวใจสำคัญ! สั่งให้ตบเมนูลงบรรทัดใหม่เมื่อที่เต็ม */
    justify-content: center; /* ✨ จัดเมนูให้อยู่กึ่งกลางสวยๆ (ถ้ากัปตันชอบชิดซ้าย ลบบรรทัดนี้ได้เลยค่ะ) */
    gap: 10px;
}

.filter-container::-webkit-scrollbar {
    display: none; 
}

.filter-chip {
    padding: 8px 18px;
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-muted);
}

.filter-chip:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.filter-chip.active {
    background-color: var(--primary);
    border-color: var(--primary);
    color: white;
    box-shadow: 0 4px 12px var(--shadow);
}

.vocab-grid {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 20px;
}

.vocab-grid.list-view {
    grid-template-columns: 1fr; 
}

.letter-header {
    grid-column: 1 / -1; 
    font-size: 28px;
    font-weight: 700;
    color: var(--primary);
    padding: 15px 0 5px;
    margin-top: 10px;
    border-bottom: 2px solid var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.letter-header:first-child {
    margin-top: 0;
}

.btn-letter-toggle {
    font-size: 13px;
    padding: 4px 14px;
    border-radius: 20px;
    border: 1px solid var(--primary);
    background-color: transparent;
    color: var(--primary);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    font-family: inherit;
}

.btn-letter-toggle:hover {
    background-color: var(--primary-light);
}

.btn-letter-toggle.active {
    background-color: var(--primary);
    color: white;
    box-shadow: 0 4px 10px var(--shadow);
}

.vocab-card {
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    position: relative;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.vocab-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 30px var(--shadow);
    border-color: rgba(222, 17, 83, 0.15);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 6px; /* ปรับลด margin ลงนิดนึงเพื่อให้คำอ่านอยู่ชิดคำศัพท์ */
}

.word-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-main);
    letter-spacing: -0.3px;
}

.part-of-speech {
    font-size: 12px;
    font-weight: 600;
    text-transform: lowercase;
    background-color: var(--primary-light);
    color: var(--primary);
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-style: italic;
}

/* ==========================================================================
   ✨ สไตล์สำหรับบรรทัดคำอ่าน (IPA Pronunciation)
   ========================================================================== */
.word-pronunciation {
    font-size: 15px;
    color: var(--text-muted);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin-bottom: 12px;
    letter-spacing: 0.5px;
}

.word-meaning {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-main);
    margin-bottom: 14px;
}

.word-example {
    font-size: 14px;
    color: var(--text-muted);
    border-left: 2px solid var(--primary);
    padding-left: 10px;
    font-style: italic;
    margin-bottom: 20px;
    flex-grow: 1;
}

.card-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border);
    padding-top: 15px;
    margin-top: auto;
}

.btn-audio {
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    font-weight: 600;
    font-size: 13px;
    transition: var(--transition);
    padding: 4px 8px;
    border-radius: var(--radius-sm);
}

.btn-audio:hover {
    background-color: var(--primary-light);
}

.admin-controls {
    display: none;
    gap: 8px;
}

body.admin-mode .admin-controls {
    display: flex;
}

.btn-icon {
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    transition: var(--transition);
}

.btn-icon:hover {
    background-color: #F0F0F0;
}

.btn-delete:hover {
    color: #DC3545;
    background-color: #FFE6E6;
}

.admin-panel-bar {
    display: none;
    background-color: #2D2D2D;
    color: white;
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 500;
}

body.admin-mode .admin-panel-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal {
    display: none;
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background-color: rgba(0,0,0,0.4);
    backdrop-filter: blur(4px);
    z-index: 200;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.modal.active {
    display: flex;
}

.modal-content {
    background-color: var(--surface);
    padding: 30px;
    border-radius: var(--radius-md);
    max-width: 500px;
    width: 100%;
    box-shadow: 0 20px 50px rgba(0,0,0,0.15);
    animation: slideUp 0.3s ease;
}

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

.modal-header {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-main);
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text-muted);
}

.form-control {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 15px;
    outline: none;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary);
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 25px;
}

@media (max-width: 600px) {
    .main-header h1 { font-size: 26px; }
    .vocab-grid { grid-template-columns: 1fr; }
    .nav-container { padding: 12px 15px; }
    .logo { font-size: 19px; }
}

/* ==========================================================================
   ✨ โหมดเกม Quiz
   ========================================================================== */
.quiz-option-btn {
    padding: 14px 20px;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    background-color: white;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
    color: var(--text-main);
    text-align: left;
}

.quiz-option-btn:hover {
    border-color: var(--primary);
    background-color: var(--primary-light);
}

/* สีตอนตอบถูก */
.quiz-option-btn.correct {
    background-color: #d4edda;
    border-color: #28a745;
    color: #155724;
}

/* สีตอนตอบผิด */
.quiz-option-btn.wrong {
    background-color: #f8d7da;
    border-color: #dc3545;
    color: #721c24;
}

.engvault-footer {
    max-width: 1200px;
    margin: 60px auto 0;
    padding: 20px;
    border-top: 1px solid var(--border); /* เส้นแบ่งจางๆ ด้านบน */
}

.footer-content {
    display: flex;
    justify-content: space-between; /* ดันแยกซ้ายขวา */
    align-items: center;
    font-size: 13px;
    color: var(--text-muted);
}

.footer-brand {
    font-weight: 600;
    color: var(--text-muted);
}

.footer-divider {
    display: none; /* ซ่อนสัญลักษณ์คั่นเพราะแยกซ้ายขวาแล้ว */
}

.designer-name {
    font-weight: 500;
    color: var(--text-main);
}

/* รองรับหน้าจอมือถือให้กลับมาเรียงตรงกลาง */
@media (max-width: 600px) {
    .footer-content {
        flex-direction: column;
        gap: 8px;
    }
}

/* ==========================================================================
   🌙 ระบบโทนสี Dark Mode 
   ========================================================================== */
body.dark-mode {
    --background: #121212;
    --surface: #1E1E1E;
    --text-main: #F5F5F5;
    --text-muted: #A0A0A0;
    --border: #2D2D2D;
    --shadow: rgba(0, 0, 0, 0.4);
    --primary-light: #2A0813; /* พื้นหลังสีชมพูเข้มสไตล์ดาร์กโทน */
}

/* ปรับแต่งรายละเอียดองค์ประกอบอื่นๆ ให้เนียนตาในโหมดมืด */
body.dark-mode .vocab-card {
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}
body.dark-mode .vocab-card:hover {
    box-shadow: 0 12px 30px rgba(222, 17, 83, 0.12);
    border-color: rgba(222, 17, 83, 0.4);
}
body.dark-mode .modal-content {
    background-color: var(--surface);
    border: 1px solid var(--border);
}
body.dark-mode select#pos,
body.dark-mode .form-control {
    background-color: #2D2D2D !important;
    color: var(--text-main);
    border-color: var(--border);
}
body.dark-mode select#pos:focus,
body.dark-mode .form-control:focus {
    border-color: var(--primary);
}
body.dark-mode .quiz-option-btn {
    background-color: #2D2D2D;
    border-color: var(--border);
    color: var(--text-main);
}
body.dark-mode .quiz-option-btn:hover {
    background-color: var(--primary-light);
    border-color: var(--primary);
}
body.dark-mode .quiz-option-btn.correct {
    background-color: #1b4322;
    color: #87e99a;
    border-color: #28a745;
}
body.dark-mode .quiz-option-btn.wrong {
    background-color: #491c1f;
    color: #fca7a9;
    border-color: #dc3545;
}
/* ========================================================= */
/* ส่วนที่ 1: จัดสไตล์โลโก้หน้าคำใน Nav Bar */
/* ========================================================= */

/* แก้ไขให้ชื่อเว็บ (ที่ตอนนี้มีรูป) เป็น Flex container */
.navbar .nav-container a.logo {
    display: flex;          /* จัดให้อักษรกับรูปอยู่บรรทัดเดียวกัน */
    align-items: center;    /* จัดให้อยู่ตรงกลางตามแนวตั้ง */
    gap: 12px;              /* เพิ่มระยะห่างระหว่างรูปกับตัวอักษร */
    text-decoration: none; /* ลบเส้นใต้ */
}

/* กำหนดขนาดรูปโลโก้ที่อยู่ใน Nav Bar */
.navbar .nav-container a.logo img {
    height: 55px;           
    width: auto;            
    object-fit: contain;     
    order: -1;              
}
/* ========================================================= */
/* 🃏 Flashcard 3D Animation & Styles (ระบบทั้งหมด - อัปเดตสีเดิม) */
/* ========================================================= */
.flashcard-game-container {
    perspective: 1000px;
    width: 100%;
}

.flashcard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: white;
    margin-bottom: 20px;
    font-weight: bold;
    font-family: 'Plus Jakarta Sans', sans-serif;
}

.btn-close-game {
    background: rgba(255,255,255,0.2);
    border: none;
    color: white;
    width: 35px;
    height: 35px;
    border-radius: 50%;
    cursor: pointer;
    transition: 0.3s;
}

.btn-close-game:hover { background: rgba(255,255,255,0.4); }

.flashcard {
    width: 100%;
    height: 400px;
    cursor: pointer;
    position: relative;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 100%;
    text-align: center;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    transform-style: preserve-3d;
}

.flashcard.is-flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-front, .flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 40px 20px;
    border-radius: 30px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.2);
}

.flashcard-front {
    background: white;
    color: #1a1a1a;
    justify-content: center;
}

.flashcard-back {
    background: #8b5cf6; /* 🌟 เปลี่ยนกลับมาใช้สีม่วงพรีเมียมสีเดิมเรียบร้อยค่ะกัปตัน */
    color: white;
    transform: rotateY(180deg);
    
    /* ระบบป้องกันข้อความล้นและรองรับการเลื่อนแนวตั้งบนมือถือ */
    overflow-y: auto;
    justify-content: flex-start;
    -webkit-overflow-scrolling: touch;
    
    padding-top: 50px;
    padding-bottom: 70px; 
}

.card-label {
    font-size: 12px;
    letter-spacing: 2px;
    font-weight: 800;
    opacity: 0.5;
    margin-bottom: 20px;
}

.flashcard-front h1 { font-size: 48px; margin: 10px 0; color: #8b5cf6; }
.flashcard-back h2 { font-size: 32px; margin-bottom: 20px; }

.example-box {
    background: rgba(255,255,255,0.1);
    padding: 20px;
    border-radius: 15px;
    text-align: left;
    width: 100%;
}

.tap-hint {
    position: absolute;
    bottom: 20px;
    font-size: 13px;
    opacity: 0.6;
}

.flashcard-back .tap-hint {
    position: relative;
    bottom: auto;
    margin-top: 20px; 
}

.flashcard-controls {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 30px;
}

.btn-game {
    background: white;
    border: none;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    font-size: 24px;
    cursor: pointer;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: 0.3s;
}

.btn-game:hover { transform: translateY(-5px); box-shadow: 0 10px 20px rgba(0,0,0,0.2); }

/* ========================================================= */
/* 📄 สไตล์ปุ่มเปลี่ยนหน้าแบบวงกลม (Pagination Circles) */
/* ========================================================= */
.page-btn {
    width: 42px;
    height: 42px;
    padding: 0;
    border-radius: 50%;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    font-weight: 600;
    font-size: 15px;
    flex-shrink: 0; /* ป้องกันปุ่มเบี้ยวบนหน้าจอมือถือ */
}
/* ========================================================= */
/* ⏳ Skeleton Loading (โครงร่างกะพริบระหว่างรอข้อมูล) */
/* ========================================================= */
.skeleton-card {
    height: 180px;
    border-radius: var(--radius-md);
    background: linear-gradient(90deg, var(--surface) 25%, var(--border) 50%, var(--surface) 75%);
    background-size: 200% 100%;
    animation: skeletonShimmer 1.5s infinite;
    border: 1px solid var(--border);
}

/* ทำให้เนียนตาในโหมด Dark Mode ด้วยค่ะ */
body.dark-mode .skeleton-card {
    background: linear-gradient(90deg, #1E1E1E 25%, #2D2D2D 50%, #1E1E1E 75%);
    background-size: 200% 100%;
    border-color: var(--border);
}

@keyframes skeletonShimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}