*, *::before, *::after {
    box-sizing: border-box;
}

:root {
    --bg-paper: #f9f8f4;      /* 宣紙色 */
    --ink-black: #2c3e50;     /* 墨色 */
    --accent-blue: #4a6572;   /* 灰藍色 */
    --accent-red: #8e443d;    /* 硃砂紅 */
    --border-color: #d1ccc0;
    --serif: 'Noto Serif TC', serif;
    --sans: 'Noto Sans TC', sans-serif;
}

body {
    background-color: var(--bg-paper);
    color: var(--ink-black);
    font-family: var(--sans);
    margin: 0;
    padding: 0;
    line-height: 1.7;
}

#loader-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: var(--bg-paper);
    z-index: 9999;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), visibility 0.8s;
}

#loader-overlay.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.loader-spinner {
    width: 50px;
    height: 50px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--accent-red);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loader-text {
    font-family: var(--serif);
    font-size: 1.1rem;
    color: var(--accent-blue);
    letter-spacing: 1px;
    text-align: center;
}

#progress-percent {
    font-size: 1.2rem;
    color: var(--accent-red);
    margin-top: 10px;
    font-weight: bold;
    font-family: var(--serif);
    transition: all 0.3s ease;
}

header {
    background-color: #fff;
    border-bottom: 1px solid var(--border-color);
    padding: 10px 20px;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.03);
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
}

header h1 {
    font-family: var(--serif);
    font-size: 1.5rem;
    margin: 0;
    letter-spacing: 2px;
    color: var(--accent-blue);
    transition: opacity 0.3s, transform 0.3s;
}

.header-search {
    display: none;
    opacity: 0;
    transform: translateY(10px);
    gap: 8px;
    align-items: center;
    transition: all 0.4s ease;
}

header.is-scrolled {
    height: 50px;
    padding: 8px 20px;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(5px);
}

header.is-scrolled h1 {
    display: none;
    opacity: 0;
}

header.is-scrolled .header-search {
    display: flex;
    opacity: 1;
    transform: translateY(0);
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 1s ease 0.3s, transform 1s ease 0.3s;
}

.container.loaded {
    opacity: 1;
    transform: translateY(0);
}

#info {
    font-size: 0.9rem;
    text-align: right;
    margin: 1rem 0;
}

.links {
    color: var(--accent-blue);
    transition: all 0.3s ease;
    cursor: pointer;
}

.links:hover {
    color: var(--accent-red);
}

.search-section {
    background: 
        linear-gradient(to right, #fdfbf6 0%, #f8f5ee 50%, #fdfbf6 100%);
    padding: 50px 20px;
    border-radius: 6px;
    text-align: center;
    border: 1px solid #e2ddd2;
    margin-bottom: 40px;
    box-shadow: 
        0 10px 30px rgba(0,0,0,0.03),
        inset 0 0 30px rgba(0,0,0,0.02);
    position: relative;
}


.search-section:hover {
    box-shadow: 0 6px 20px rgba(0,0,0,0.04);
}

.search-label {
    font-family: var(--serif);
    display: block;
    margin-bottom: 35px;
    font-size: 1rem;
    color: var(--accent-blue);
    letter-spacing: 3px;
    position: relative;
}

.search-label::after {
    content: "";
    display: block;
    width: 120px;
    height: 1px;
    background: var(--accent-red);
    margin: 15px auto 0;
    opacity: 0.4;
}

.search-box {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: nowrap;
}

.input-field {
    --size: 60px;
    --third: calc(var(--size) / 3);

    width: var(--size);
    height: var(--size);

    font-size: 36px;
    font-family: var(--serif);
    text-align: center;
    border: 1.5px solid var(--border-color);
    margin: 0;
    border-radius: 4px;
    outline: none;
    background-color: #fbf9f3;
    padding: 0;

    background-image:
        linear-gradient(to right,
            transparent var(--third),
            rgba(142,68,61,0.18) var(--third),
            rgba(142,68,61,0.18) calc(var(--third) + 1px),
            transparent calc(var(--third) + 1px)
        ),
        linear-gradient(to right,
            transparent calc(var(--third) * 2),
            rgba(142,68,61,0.18) calc(var(--third) * 2),
            rgba(142,68,61,0.18) calc(var(--third) * 2 + 1px),
            transparent calc(var(--third) * 2 + 1px)
        ),
        linear-gradient(to bottom,
            transparent var(--third),
            rgba(142,68,61,0.18) var(--third),
            rgba(142,68,61,0.18) calc(var(--third) + 1px),
            transparent calc(var(--third) + 1px)
        ),
        linear-gradient(to bottom,
            transparent calc(var(--third) * 2),
            rgba(142,68,61,0.18) calc(var(--third) * 2),
            rgba(142,68,61,0.18) calc(var(--third) * 2 + 1px),
            transparent calc(var(--third) * 2 + 1px)
        );

    background-repeat: no-repeat;
}

.input-field:disabled {
    background-color: #f5f5f5;
    cursor: not-allowed;
    color: #ccc;
}

.input-field:focus {
    border-color: var(--accent-red);
    transform: scale(1.05);
    box-shadow: 0 0 15px rgba(142, 68, 61, 0.15);
}

.input-mini {
    width: 30px;
    height: 30px;
    font-size: 16px;
    border-width: 1px;

    background-image:
        /* 直線 10px */
        linear-gradient(to right,
            transparent 10px,
            rgba(142,68,61,0.18) 10px,
            rgba(142,68,61,0.18) 11px,
            transparent 11px
        ),
        /* 直線 20px */
        linear-gradient(to right,
            transparent 20px,
            rgba(142,68,61,0.18) 20px,
            rgba(142,68,61,0.18) 21px,
            transparent 21px
        ),
        /* 橫線 10px */
        linear-gradient(to bottom,
            transparent 10px,
            rgba(142,68,61,0.18) 10px,
            rgba(142,68,61,0.18) 11px,
            transparent 11px
        ),
        /* 橫線 20px */
        linear-gradient(to bottom,
            transparent 20px,
            rgba(142,68,61,0.18) 20px,
            rgba(142,68,61,0.18) 21px,
            transparent 21px
        );

    background-repeat: no-repeat;
}

.statistics {
    margin-top: 25px;
    font-size: 0.9rem;
    color: #888;
    font-family: var(--sans);
    min-height: 1.5em;
}

.table-wrapper {
    margin-top: 20px;
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
    border: 1px solid var(--border-color);
}

th {
    font-family: var(--serif);
    background-color: #f0eeea;
    color: var(--accent-blue);
    padding: 15px;
    text-align: center; 
    border-bottom: 2px solid var(--border-color);
    font-size: 1rem;
}

td {
    padding: 18px 15px;
    border-bottom: 1px solid #eee;
    vertical-align: top;
}

.idiom-word {
    font-family: var(--sans);
    font-weight: 700;
    font-size: 1.2rem;
    min-width: 80px;
    text-align: center; 
    white-space: nowrap;
    word-break: keep-all;
}

a {
    color: var(--accent-red);
    text-decoration: none;
    transition: all 0.3s ease;
    position: relative;
}

a:hover {
    opacity: 0.7;
}

.explanation-text {
    font-family: var(--sans);
    color: #444;
    line-height: 1.8;
    font-size: 0.95rem;
    text-align: justify; 
}

.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(44, 62, 80, 0.4);
    backdrop-filter: blur(8px);
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: var(--bg-paper);
    margin: 20px;
    padding: 40px;
    border: 1px solid var(--border-color);
    width: 90%;
    max-width: 650px;
    border-radius: 8px;
    position: relative;
    box-shadow: 0 25px 50px rgba(0,0,0,0.15);
    transform: translateY(30px);
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.modal.active .modal-content {
    transform: translateY(0);
    opacity: 1;
    top: 30px;
}

.close-modal {
    position: absolute;
    right: 25px;
    top: 20px;
    font-size: 32px;
    font-weight: 300;
    color: #999;
    cursor: pointer;
    transition: color 0.3s;
    line-height: 1;
}

.close-modal:hover {
    color: var(--accent-red);
}

.modal-body {
    font-family: var(--sans);
    font-size: 0.95rem;
    color: #555;
    max-height: 65vh;
    overflow-y: auto;
    padding-right: 15px;
}

.modal-body h2 { color: var(--accent-blue); margin-top: 0; font-family: var(--serif); }
.modal-body h3 { 
        font-family: var(--serif); 
        color: var(--accent-blue); 
        border-left: 4px solid var(--accent-red); 
        padding-left: 12px;
        margin-top: 30px;
}

.modal-body ul { padding-left: 20px; list-style-type: square; }
.modal-body li { margin-bottom: 12px; }

@media (max-width: 480px) {
    .search-box { gap: 8px; }
    header h1 { font-size: 1.2rem; }
    .modal-content { padding: 30px 20px; }
}