* {
    transition: all 0.25s ease;
    -webkit-transition: all 0.25s ease;
    -moz-transition: all 0.25s ease;
    -o-transition: all 0.25s ease;
    -ms-transition: all 0.25s ease;
    padding: 0;
    margin: 0;
}
html, body { width: 100%; }
body {
    background: #16a085;
    font-family: "Helvetica Neue", Helvetica, Microsoft Yahei, Hiragino Sans GB, WenQuanYi Micro Hei, sans-serif;
    -webkit-font-smoothing: antialiased;
    padding-top: 20px;
}
a { text-decoration: none; }
a:hover, a:focus { text-shadow: 0 1px 1px #555; }
#particles {
    position: fixed; right: 0; bottom: 0;
    min-width: 100%; min-height: 100%;
    height: auto; width: auto; z-index: -1;
}
.web-title { color: #fff; margin: 25px 0 30px 0; }
.web-title h1 { font-size: 28px; }
.web-title p { font-size: 14px; color: #e7e7e7; margin-top: 5px; }
.main-footer, .main-footer a { color: #fff; }
.main-footer .row a { padding-left: 10px; }
.main-footer .row { margin-bottom: 50px; }
@media (min-width: 770px) { .navbar-brand { display: none; } }
@media (max-width: 770px) {
    .web-title { display: none; }
    .nav-main { padding: 0; }
}
.panel { margin-top: 20px; }
.panel-heading { font-weight: 700; font-size: 16px; }
textarea {
    width: 100%;
    min-height: 220px;
    padding: 15px;
    font-size: 16px;
    line-height: 1.8;
    border: 1px solid #ddd;
    border-radius: 4px;
    resize: vertical;
    font-family: inherit;
    box-sizing: border-box;
}
textarea:focus {
    border-color: #16a085;
    outline: none;
    box-shadow: 0 0 8px rgba(22,160,133,0.3);
}
.mb-10 { margin-bottom: 10px; }
.mt-10 { margin-top: 10px; }
.btn-convert {
    padding: 10px 30px;
    font-size: 16px;
    font-weight: 700;
    background: linear-gradient(135deg, #16a085, #1abc9c);
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    margin: 0 5px;
}
.btn-convert:hover { opacity: 0.9; box-shadow: 0 2px 10px rgba(22,160,133,0.4); }
.btn-convert:active { transform: scale(0.98); }
.btn-swap {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: 20px;
    border: 1px solid #ddd;
    background: #fff;
    cursor: pointer;
}
.btn-swap:hover { border-color: #16a085; color: #16a085; }
.toolbar { display: flex; gap: 8px; flex-wrap: wrap; margin: 10px 0; align-items: center; justify-content: center; }
.output-area {
    background: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 4px;
    min-height: 220px;
    padding: 15px;
    font-size: 16px;
    line-height: 1.8;
    word-wrap: break-word;
    white-space: pre-wrap;
    position: relative;
}
.copy-btn {
    position: absolute;
    top: 8px; right: 8px;
    padding: 4px 12px;
    font-size: 12px;
    border-radius: 4px;
    border: 1px solid #ddd;
    background: #fff;
    cursor: pointer;
}
.copy-btn:hover { border-color: #16a085; color: #16a085; }
.direction-badge {
    display: inline-block;
    padding: 4px 14px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
    background: #e8f5e9;
    color: #16a085;
}
.char-count { font-size: 13px; color: #6c757d; margin-top: 5px; }
.desc-section h3 { font-size: 18px; color: #16a085; margin: 20px 0 10px; border-left: 4px solid #16a085; padding-left: 12px; }
.desc-section h4 { font-size: 15px; color: #333; margin: 12px 0 6px; }
.desc-section p, .desc-section li { font-size: 14px; line-height: 1.8; color: #555; }
.desc-section ul, .desc-section ol { padding-left: 20px; }
.desc-section li { margin-bottom: 4px; }
.desc-section .highlight-box { background: #f8f9fa; border-left: 3px solid #16a085; padding: 10px 15px; margin: 10px 0; border-radius: 0 4px 4px 0; }
.faq-item { border-bottom: 1px solid #eee; padding: 10px 0; }
.faq-item:last-child { border-bottom: none; }
.faq-q { font-weight: 700; color: #16a085; cursor: pointer; }
.faq-a { margin-top: 4px; color: #555; font-size: 14px; line-height: 1.7; }