/* --- 核心黑金視覺樣式 --- */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "PingFang TC", "Microsoft JhengHei", sans-serif;
        }

        body, html {
            width: 100%;
            height: 100%;
            background-color: #000;
            overflow: hidden; /* 防止小螢幕出現奇怪捲軸 */
        }

        /* 登入頁背景容器 */
        .login-page {
            width: 100%;
            height: 100vh;
            background: radial-gradient(circle at center, #2c2c2c 0%, #000000 100%);
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 20px;
        }

        /* 登入主體卡片 */
        .login-card {
            width: 100%;
            max-width: 400px;
            padding: 40px 30px;
            border-radius: 20px;
            background: rgba(255, 255, 255, 0.03);
            border: 1px solid rgba(241, 196, 15, 0.1);
            backdrop-filter: blur(10px);
            text-align: center;
            box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
        }

        /* Logo 區域 */
        .brand-area {
            margin-bottom: 40px;
        }

        .brand-logo {
            width: 80px;
            height: 80px;
            background: linear-gradient(135deg, #f1c40f, #d4ac0d);
            border-radius: 50%;
            margin: 0 auto 15px;
            display: flex;
            justify-content: center;
            align-items: center;
            font-size: 40px;
            color: #000;
            box-shadow: 0 0 20px rgba(241, 196, 15, 0.4);
        }

        .brand-name {
            color: #f1c40f;
            font-size: 24px;
            font-weight: bold;
            letter-spacing: 4px;
            text-shadow: 0 2px 4px rgba(0,0,0,0.5);
        }

        /* 輸入框組 */
        .input-wrapper {
            margin-bottom: 20px;
            position: relative;
        }

        .input-field {
            width: 100%;
            height: 55px;
            background: rgba(255, 255, 255, 0.05);
            border: 1px solid #333;
            border-radius: 12px;
            padding: 0 50px;
            color: #fff;
            font-size: 16px;
            outline: none;
            transition: all 0.3s ease;
        }

        .input-field:focus {
            border-color: #f1c40f;
            background: rgba(255, 255, 255, 0.08);
            box-shadow: 0 0 15px rgba(241, 196, 15, 0.2);
        }

        .input-icon {
            position: absolute;
            left: 18px;
            top: 50%;
            transform: translateY(-50%);
            color: #888;
            transition: color 0.3s;
        }

        .input-field:focus + .input-icon {
            color: #f1c40f;
        }

        /* 功能選項 */
        .form-options {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 30px;
            font-size: 14px;
            color: #aaa;
        }

        .remember-label {
            display: flex;
            align-items: center;
            cursor: pointer;
        }

        .remember-label input {
            margin-right: 8px;
            accent-color: #f1c40f;
        }

        .forgot-pw {
            color: #f1c40f;
            text-decoration: none;
        }

        /* 登入按鈕 */
        .btn-login {
            width: 100%;
            height: 55px;
            background: linear-gradient(180deg, #f1c40f 0%, #d4ac0d 100%);
            border: none;
            border-radius: 12px;
            color: #000;
            font-size: 18px;
            font-weight: bold;
            cursor: pointer;
            box-shadow: 0 5px 15px rgba(241, 196, 15, 0.3);
            transition: transform 0.2s, opacity 0.2s;
            margin-bottom: 25px;
        }

        .btn-login:active {
            transform: scale(0.98);
            opacity: 0.9;
        }

        /* 註冊導引 */
        .footer-links {
            color: #888;
            font-size: 14px;
        }

        .btn-reg {
            color: #f1c40f;
            text-decoration: none;
            font-weight: bold;
            margin-left: 5px;
        }

        /* --- 針對小螢幕 iPhone SE 優化 --- */
        @media screen and (max-height: 600px) {
            .login-card {
                padding: 20px;
            }
            .brand-area {
                margin-bottom: 20px;
            }
            .brand-logo {
                width: 60px;
                height: 60px;
                font-size: 30px;
            }
            .input-field {
                height: 48px;
            }
        }
        /* 自定義 Alert 遮罩 */
        .m-alert-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.75);
            display: none; /* 初始隱藏 */
            justify-content: center;
            align-items: center;
            z-index: 10000; /* 確保在最上層 */
            backdrop-filter: blur(4px);
        }

        /* Alert 視窗主體 */
        .m-alert-box {
            width: 85%;
            max-width: 320px;
            background: #1a1a1a;
            border: 1px solid #f1c40f;
            border-radius: 15px;
            padding: 25px;
            text-align: center;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
            animation: alertFadeIn 0.3s ease-out;
        }

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

        .m-alert-title {
            color: #f1c40f;
            font-size: 18px;
            font-weight: bold;
            margin-bottom: 12px;
            letter-spacing: 1px;
        }

        .m-alert-msg {
            color: #ddd;
            font-size: 15px;
            line-height: 1.6;
            margin-bottom: 25px;
        }

        .m-alert-btn {
            width: 100%;
            height: 45px;
            background: linear-gradient(180deg, #f1c40f 0%, #d4ac0d 100%);
            border: none;
            border-radius: 8px;
            color: #000;
            font-weight: bold;
            font-size: 16px;
            cursor: pointer;
            box-shadow: 0 4px 10px rgba(241, 196, 15, 0.2);
        }

        .m-alert-btn:active {
            opacity: 0.8;
            transform: scale(0.98);
        }

        .btn-login {
            width: 100%;
            height: 55px;
            background: linear-gradient(180deg, #f1c40f 0%, #d4ac0d 100%);
            border: none;
            border-radius: 12px;
            color: #000;
            font-size: 18px;
            font-weight: bold;
            cursor: pointer;
            position: relative; /* 為了閃光特效 */
            overflow: hidden;   /* 為了閃光特效 */
            box-shadow: 0 5px 15px rgba(241, 196, 15, 0.3);
            transition: all 0.1s ease; /* 縮短時間，反應更靈敏 */
        }
        
       
        /* 1. 流光容器：定義按鈕的大小與圓角 */
.btn-flow-wrap {
    position: relative;
    width: 100%;
    height: 58px; /* 比內部按鈕稍微大一點點 */
    padding: 2px; /* 這就是流光露出來的寬度 */
    background: rgba(0, 0, 0, 0.2);
    border-radius: 14px;
    overflow: hidden; /* 隱藏旋轉層溢出的部分 */
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
}

/* 2. 旋轉的光源層 (底層) */
.btn-flow-wrap::before {
    content: '';
    position: absolute;
    width: 150%;
    height: 300%;
    /* 錐形漸層：產生一道強光，其餘透明 */
    background: conic-gradient(
        transparent, 
        transparent, 
        transparent, 
        #f1c40f, /* 金色光點 */
        transparent
    );
    animation: rotateFlow 2s linear infinite; /* 2秒繞一圈 */
}

@keyframes rotateFlow {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* 3. 內部的實體按鈕 (覆蓋在旋轉層之上) */
.btn-login-flow {
    position: relative;
    z-index: 1; /* 確保按鈕在光芒上方 */
    width: 100%;
    height: 100%;
    background: #1a1a1a; /* 稍微深一點，對比流光更明顯 */
    background: linear-gradient(180deg, #2a2a2a 0%, #111 100%);
    border: none;
    border-radius: 12px;
    color: #f1c40f;
    font-size: 18px;
    font-weight: bold;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: all 0.2s;
}

/* 4. 點擊回饋：整體縮放 */
.btn-flow-wrap:active {
    transform: scale(0.96);
}

.btn-flow-wrap:active .btn-login-flow {
    background: #000; /* 點擊時按鈕變暗，光芒顯得更亮 */
}

/* 容器：定義邊框的厚度 (2px) */
.btn-flow-wrap {
    position: relative;
    width: 100%;
    height: 55px;
    border-radius: 12px;
    padding: 2px; /* 這裡決定了邊框流動的粗細 */
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000; /* 背景黑，光才亮 */
}

/* 旋轉雷射光：這是流動感的關鍵 */
.btn-flow-wrap::before {
    content: "";
    position: absolute;
    width: 150%;  /* 寬度擴大確保旋轉覆蓋四角 */
    height: 300%; 
    /* 強力修正：讓金色光束變得極窄 (10% 左右)，其餘全黑 */
   
    animation: laserRotate 1.5s linear infinite; /* 縮短時間到 1.5s，增加動感 */
}

/* 強制旋轉動畫 */
@keyframes laserRotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* 內部按鈕：遮住中間，只露出邊緣 2px 的光 */
.btn-login-flow {
    position: relative;
    z-index: 2;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, #2a2a2a 0%, #0a0a0a 100%);
    border: none;
    border-radius: 10px; /* 稍微比外層小一點 */
    color: #f1c40f;
    font-size: 18px;
    font-weight: bold;
    letter-spacing: 2px;
    cursor: pointer;
}

/* 點擊效果 */
.btn-flow-wrap:active {
    transform: scale(0.96);
}
.btn-flow-wrap {
    position: relative;
    width: 100%;
    height: 55px;
    border-radius: 12px;
    padding: 2px;
    overflow: hidden; /* 確保內部旋轉物不外溢 */
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000;
    /* 核心修正：強制開啟硬體加速與裁切 */
    -webkit-mask-image: -webkit-radial-gradient(white, black);
    isolation: isolate; 
}

/* 旋轉雷射光層 */
.btn-flow-wrap::before {
    content: "";
    position: absolute;
    /* 修正：寬高設為直徑，確保旋轉時永遠覆蓋但不會有銳角 */
    width: 200%; 
    height: 500%; 
    background: conic-gradient(
        from 0deg,
        transparent 0deg,
        transparent 150deg,
        #f1c40f 180deg, /* 只有這裡有光 */
        transparent 210deg,
        transparent 360deg
    );
    animation: laserRotate 2s linear infinite;
    /* 修正：確保旋轉中心準確 */
    transform-origin: center;
}

@keyframes laserRotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* 內部按鈕層 */
.btn-login-flow {
    position: relative;
    z-index: 10;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, #2a2a2a 0%, #050505 100%);
    border: none;
    border-radius: 10px;
    color: #f1c40f;
    font-size: 18px;
    font-weight: bold;
    letter-spacing: 2px;
    cursor: pointer;
    /* 防止點擊時出現系統預設的藍色高亮 */
    -webkit-tap-highlight-color: transparent;
}

/* 點擊縮放效果：連同容器一起縮放，才不會露出底層 */
.btn-flow-wrap:active {
    transform: scale(0.96);
    transition: transform 0.1s;
}

.btn-svg-wrap {
    position: relative;
    width: 100%;
    height: 55px;
    background: #000;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: visible; /* SVG 稍微超出也沒關係 */
}

/* SVG 容器 */
.svg-border {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none; /* 讓點擊穿透到按鈕上 */
}

/* SVG 矩形路徑 */
.svg-border rect {
    fill: none;
    stroke: #f1c40f; /* 金色線條 */
    stroke-width: 4; /* 線條粗細 */
    width: 100%;
    height: 100%;
    rx: 12; ry: 12;
    /* 1. 定義線段長度與間距 (例如 80px 長, 400px 間距) */
    stroke-dasharray: 80, 400; 
    /* 2. 動畫：讓線段偏移 */
    animation: dashFlow 2s linear infinite;
}

@keyframes dashFlow {
    from { stroke-dashoffset: 480; } /* 總長度 */
    to { stroke-dashoffset: 0; }
}

.btn-login-final {
    width: calc(100% - 4px); /* 留一點空間給邊框 */
    height: calc(100% - 4px);
    background: linear-gradient(180deg, #2a2a2a 0%, #050505 100%);
    border: none;
    border-radius: 10px;
    color: #f1c40f;
    font-size: 18px;
    font-weight: bold;
    letter-spacing: 2px;
    cursor: pointer;
    z-index: 2;
    -webkit-tap-highlight-color: transparent;
}

/* 點擊縮放：這次縮放非常乾淨 */
.btn-svg-wrap:active {
    transform: scale(0.96);
    transition: transform 0.1s;
}