:root {
    --main: #236de4;
    --main-dark: #153e73;
    --accent: #1fd6ba;
    --bg: #f7fbff;
}
body {
    background: var(--bg);
    margin: 0;
    font-family: "Segoe UI", Arial, sans-serif;
    color: #234;
}
.container {
    max-width: 470px;
    margin: 38px auto 0 auto;
    background: #fff;
    border-radius: 18px;
    box-shadow: 0 4px 26px #236de420;
    padding: 30px 18px 22px 18px;
    min-height: 600px;
    position: relative;
}
.logo {
    font-size: 1.35em;
    font-weight: bold;
    text-align: center;
    color: var(--main-dark);
    margin-bottom: 7px;
    letter-spacing: -1px;
}
.mode-toggle {
    display: flex;
    gap: 8px;
    margin: 18px 0 18px 0;
    justify-content: center;
    flex-wrap: wrap;
}
.toggle-btn {
    flex: 1 1 90px;
    background: #f4f8fe;
    color: var(--main-dark);
    border: 1.4px solid #d1e2fc;
    border-radius: 8px;
    font-size: 1.01em;
    font-weight: 600;
    padding: 0.69em 0;
    cursor: pointer;
    transition:
        background 0.15s,
        color 0.13s;
    outline: none;
    margin-bottom: 2px;
}
.toggle-btn.active {
    background: var(--main);
    color: #fff;
    border-color: var(--main);
    box-shadow: 0 3px 14px #236de420;
}
.desc {
    text-align: center;
    color: #286673;
    margin-bottom: 16px;
    font-size: 1.05em;
}
.uploader {
    margin: 0 auto 20px auto;
    border: 2px dashed #c3d9f9;
    border-radius: 11px;
    background: #f7fbff;
    text-align: center;
    padding: 30px 12px;
    font-size: 1.05em;
    color: #356;
    cursor: pointer;
    transition:
        border 0.2s,
        background 0.15s;
    position: relative;
}
.uploader.dragover {
    border-color: var(--main);
    background: #ecf4ff;
}
.uploader input[type="file"] {
    display: none;
}
.file-list {
    margin: 8px 0 12px 0;
    padding: 0;
    list-style: none;
    font-size: 0.98em;
}
.file-list li {
    margin: 0 0 7px 0;
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 4px 0 4px 0;
    border-bottom: 1px solid #e7eefa;
}
.file-list .move-btn {
    background: #dbe9fa;
    border: none;
    border-radius: 4px;
    font-size: 1.1em;
    cursor: pointer;
    padding: 2px 6px;
    color: var(--main-dark);
    transition: background 0.13s;
}
.file-list .move-btn:active {
    background: #bdd2f9;
}
.input-row {
    display: flex;
    align-items: center;
    gap: 7px;
    margin: 10px 0 10px 0;
}
.input-row label {
    font-size: 0.98em;
    color: #356;
    min-width: 98px;
}
.input-row input[type="text"],
.input-row input[type="number"],
.input-row input[type="password"] {
    flex: 1;
    padding: 7px 8px;
    font-size: 1.05em;
    border: 1.3px solid #b5d2fa;
    border-radius: 7px;
    background: #fafdff;
    color: #234;
}
.input-row input[type="range"] {
    width: 100%;
    accent-color: var(--main);
}
.input-hint {
    color: #29b48a;
    font-size: 0.97em;
    margin-left: 7px;
    font-style: italic;
    opacity: 0.95;
}
.split-mode-row {
    margin-bottom: 10px;
    display: flex;
    gap: 15px;
    align-items: center;
    font-size: 0.99em;
}
.split-mode-row label {
    cursor: pointer;
}
.action-btn {
    background: var(--main);
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 12px 0;
    width: 100%;
    font-size: 1.15em;
    font-weight: bold;
    cursor: pointer;
    margin-top: 17px;
    margin-bottom: 12px;
    transition: background 0.16s;
    box-shadow: 0 2px 12px #236de416;
}
.action-btn:active {
    background: var(--main-dark);
}
.download-link {
    display: block;
    margin: 18px auto 0 auto;
    text-align: center;
    font-size: 1.09em;
    font-weight: 500;
    color: #19788a;
    background: #e1f7fb;
    border-radius: 7px;
    padding: 10px 2px;
    width: 96%;
    text-decoration: none;
    word-break: break-all;
    transition: background 0.15s;
}
.download-link:hover {
    background: #b7e9ee;
}
#faq {
    margin: 38px 0 0 0;
    background: #f7fbff;
    border-radius: 13px;
    border: 1.2px solid #dde7fc;
    padding: 22px 17px 17px 17px;
    font-size: 1.04em;
}
#faq dl {
    margin: 0;
}
#faq dt {
    font-weight: bold;
    margin-top: 11px;
    color: #2462a8;
}
#faq dd {
    margin: 2px 0 9px 0;
    color: #154185;
    margin-left: 7px;
}
.footer {
    color: #789;
    text-align: center;
    font-size: 0.95em;
    margin-top: 23px;
    line-height: 1.6;
    opacity: 0.88;
}
@media (max-width: 700px) {
    .container {
        max-width: 99vw;
        padding: 12px 2vw 16px 2vw;
    }
    .logo {
        font-size: 1.1em;
    }
    .action-btn {
        font-size: 1.01em;
    }
    .mode-toggle {
        gap: 5px;
    }
    .input-row label {
        min-width: 60px;
    }
}
#backBtn {
    position: fixed;
    left: 50%;
    bottom: 32px;
    transform: translateX(-50%);
    background: #236de4;
    color: #fff;
    font-weight: 700;
    border: none;
    border-radius: 2rem;
    padding: 0.58em 1.5em;
    box-shadow: 0 4px 16px #13d2b066;
    font-size: 1.09em;
    text-decoration: none;
    cursor: pointer;
    letter-spacing: 0.01em;
    transition:
        background 0.15s,
        transform 0.12s;
    z-index: 2000;
}
#backBtn:hover {
    background: #0e8078;
    transform: translateX(-50%) scale(1.04);
}
@media (max-width: 600px) {
    #backBtn {
        bottom: 18px;
        font-size: 0.98em;
        padding: 0.48em 1em;
    }
}